The invention relates to novel material comprising X/hard carbon composite and to a process for their preparation, the process comprising the steps: a) forming a mixture comprising i) one or more hard carbon-starting materials, ii) one or more starting materials which comprise one or more of the component elements of X, and optionally iii) one or more secondary carbon-containing materials; and b) heating the resulting mixture at 100° C. to 1500° C. to yield the material comprising the X/hard carbon composite; wherein X comprises one or more component elements selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel and wherein X is present in an amount of at least 5% by weight of the material comprising the X/hard carbon composite.

Sodium-ion batteries are analogous in many ways to the lithium-ion batteries that are in common use today; they are both reusable secondary batteries that comprise an anode (negative electrode), a cathode (positive electrode) and an electrolyte material, both are capable of storing energy, and they both charge and discharge via a similar reaction mechanism. When a sodium-ion (or lithium-ion battery) is charging, Na+ (or Li+) ions de-intercalate from the cathode and insert into the anode. Meanwhile charge balancing electrons pass from the cathode through the external circuit containing the charger and into the anode of the battery. During discharge the same process occurs but in the opposite direction.
Lithium-ion battery technology has enjoyed a lot of attention in recent years and provides the preferred portable battery for most electronic devices in use today; however lithium is not a cheap metal to source and is considered too expensive for use in large scale applications. By contrast sodium-ion battery technology is still in its relative infancy but is seen as advantageous; sodium is much more abundant than lithium and some researchers predict this will provide a cheaper and more durable way to store energy into the future, particularly for large scale applications such as storing energy on the electrical grid. Nevertheless a lot of work has yet to be done before sodium-ion batteries are a commercial reality.
One area that needs more attention is the development of suitable anode materials, particularly for sodium-ion batteries.
Carbon, in the form of graphite, has been favoured for some time as an anode material in lithium-ion batteries due to its high gravimetric and volumetric capacity; graphite electrodes deliver reversible capacity of more than 360 mAh/g, comparable to the theoretical capacity of 372 mAh/g. The electrochemical reduction process involves Li+ ions being inserted into the van der Waals gap between the graphene layers, to yield LiC6. Unfortunately however, graphite is much less electrochemically active towards sodium and this, coupled with the fact that sodium has a significantly larger atomic radius compared with lithium, results in the intercalation between graphene layers in graphite anodes being severely restricted in sodium-ion cells.
Anodes made using hard carbon materials with disordered structures on the other hand, are known to overcome some of the insertion issues for sodium ions. The exact structure of hard carbon materials has still to be resolved, but in general terms hard carbon is described as a non-graphitizable, non-crystalline carbon material. Hard carbon has layers, but these are not neatly stacked, and it has micropores (micro-sized pores) formed between the disorderly stacked carbon layers. At the macroscopic level, hard carbon is isotropic. One of the reasons why it is difficult to construct a universal structural model of hard carbon is that detailed structures, domain size, fraction of carbon layers and micropores depend on the synthesis conditions, such as carbon sources and carbonization temperatures. Typical methods of hard carbon production employ starting materials such as sucrose, glucose, petroleum coke or pitch coke, which are mixed with a thermoplastic binder such as coal tar, petroleum based pitch or a synthetic resin, and then heated up to about 1200° C. However, despite being better than graphite, such hard carbon materials only provide a usable capacity in sodium-ion batteries below 300 mAh/g and suffer from slow insertion kinetics and low volumetric energy density.
As discussed in J Mater. Chem. A, 2015, 3, 5708, over the last few years, Na-storable metals and alloys have been identified as high-capacity anodes, including Sn (847 mAh/g, Na15Sn4), Sb (660 mAh/g, Na3Sb), Ge (1108 mAh/g, Na3Ge) and Pb (484 mAh/g, Na15Pb4). However, the structural stability of these materials suffer from severe changes in expansion and contraction when Na is inserted and extracted during the charge/discharge process. For example, the change in volume is 525% for Sn and 390% for Sb, and the continual expansion and contraction causes the metals to fatigue, and undergo a pulverization process.
Attempts to address this problem have included i) reducing the metal particle size to nanoscale (<10 nm) in order to mitigate the strain induced by the large volume changes, and to retard pulverization; and ii) uniformly dispersing nanosized materials within conductive matrices to accommodate the volume changes and maintain the mechanical integrity of the composite electrode. For example, in Chem. Commun., 2012, 48, 3321, Xiao et al report that a Sb/Sn/C nano-composite material with a Na storage capacity of about 500 mAh/g and good cycling stability, can be prepared by combining the components of the composite material (Sb, Sn and C) using a high-energy mechanical milling (HEMM) process conducted under an argon atmosphere. The metal:carbon black (C65™ carbon) weight ratio was set to 7:3 and the Sn:Sb ratio was 1:1 by molar ratio. However, whilst such a technique allows the nano-particle size of the product to be controlled by varying the milling time and choice of milling media, the process is expected to be expensive to run on a large scale and likely only to be useful for making very small amounts of product, of the order of 5-10 g per batch. The use of larger quantities of materials is likely to cause serious abrasion to the milling equipment. Moreover, the HEMM method is known to generate a good degree of heat which will be sufficient to melt low melting metals such as tin, and this will cause handling difficulties. Therefore, the HEMM process is likely to be uneconomic for commercial anode material production.
Numerous workers have pursued other ways to provide nanosized materials that are uniformly dispersed within conductive matrices. For example, US2003/0138698 discloses making carbonaceous materials coated with a metal or metal oxide for a lithium secondary battery by a gas suspension spray coating process. Firstly, particles of carbon active material are made to float in a gas, then a solution of a metal salt is sprayed onto the floating carbon particles. The resulting coated particles are dried to coat the metal salt onto the surface of the particles and then heated to form a cluster or thin film of metal or metal oxide on the surface of the particles. Although reasonable percentage cycle life results are reported, it is believed that an anode particle coated with a very thin metallic film will not be very robust and is likely to suffer when the overall particle expands and contracts during charge and discharge. Moreover, the positive effect of such a thin metallic film on discharge capacity only looks to be minimal with the results for materials with the thin metal film being recorded as just over 300 mAh/g.
X. He et al disclose, in Electrochimica Acta 52 (2006) 1221-1225, the preparation of Sn2Sb alloy encapsulated within carbon microsphere anode materials for lithium-ion batteries by carbothermal reduction of oxides. In particular they disclose using an inverse emulsion polymerisation of resorcinol-formaldehyde in the presence of Sb2O3 and SnO2 powders. Similarly, Scrosati and co-workers report in WO2010095082A1 that nanostructured Sn/C composite anode materials can be prepared by engulfing a Sn-based organometallic compound in a resorcinol-formaldehyde gel, followed by calcining the resultant material in an argon atmosphere to reduce the tin in the tin metallic precursor and to carbonize the gel. Further, Xu et al, in J. Mater. Chem 2012, 22, 9562, teach sponge-like porous carbon/Sn composite anodes made by dispersing SnO2 nanoparticles in a soft template polymer followed by carbonisation. US2012/0040249 discloses providing a metallic material precursor (including at least one of Cu, Ni, Ag, Au and Pt) on the surface of a carbon material by mixing small amounts (1 wt % of the reaction mixture) of a metallic material precursor with a carbon material, coating the surface with a carbon precursor and heating the resulting mixture at 700° C. to 1500° C. for about 1 to about 8 hours to yield 1 nm to 100 nm sized particles of metal distributed over a carbon core with a further carbon film covering the carbon core particles and the metallic material. Reasonable percentage cycle life results are reported, but there is no indication in this document that the very low amounts of metal that are available to be deposited on carbon material will produce any positive effect to increase the discharge capacity compared against carbon material without a metal coating.
In J. Power Sources 284 (2015) 287-295, Shirley Meng et al. describe making SnO2/hard carbon composite material starting from a reaction mixture containing SnCl4, aqueous ammonia and glucose. However, although these processes may lend themselves better to commercial scaling, the formation of hard carbon in situ during a carbonisation process, means that it is difficult to control the nano-metal/hard carbon particle size, and to disperse the metal particles uniformly in the hard carbon matrix. Further, it has so far not been possible to prepare SnO/hard carbon nano-composite material as attempts to prepare such a material by Shirley Meng et al in the literature discussed above failed, due to the SnO being oxidized to SnO2 during the decomposition of the carbon precursor.
Also recently, in J. Mater. Chem. A, 2015, 3, 5708-5713, Wu, Lu, Xiao et al. describe an aerosol spray drying technique to prepare Sb/C microspheres starting from a mixture containing polyacrylonitrile and SbCl3 dissolved in dimethylformamide which is firstly vigorously stirred at 60° for 12 hours, before using this mixture for spray drying, followed by collecting the resulting particles, heating them at 280° C. for 6 hours to consolidate their spherical morphology, and then heating them again at 700° C. for 6 hours to obtain the Sb/C microspheres. Although the desired outcome of discrete microsperes with well-dispersed, ultra-small Sn particles within a carbon matrix appears to be achieved, this process is complicated and would be expensive to perform, especially on a commercial scale.
The aim of the present invention is to provide novel hard carbon composite materials for use as anode-active materials in alkali metal-ion energy storage systems, for example lithium-ion batteries and particularly for sodium-ion batteries. The aim is also to provide a new process for the preparation of such new hard carbon composite materials. The new hard carbon composite materials will deliver an excellent first discharge specific capacity and exhibit high first discharge capacity efficiency, the process for their preparation will be cost effective, especially on a commercial scale, and will use readily available starting materials that do not require complex handling conditions. The ability of the process to prepare hard carbon composite materials with elements with a low melting point such as tin, is especially important. Further advantageous aims of the present invention are to provide hard carbon composites in which i) the particle size of each constituent of the hard carbon composite is controlled, ii) each of the constituents is uniformly dispersed and iii) the amount of each constituent is predetermined. Ideally, the process of the present invention will be straightforward to carry out, preferably in a single step, it will be able to produce the desired composite in good yield, and finally, it will be able to produce hard carbon composite materials that are able to be used directly, i.e. without the need for separation or purification steps.
In a first embodiment, the present invention therefore provides a process for preparing a material comprising an X/hard carbon composite, the process comprising the steps:                a) forming a mixture comprising i) one or more hard carbon starting materials, ii) one or more starting materials which comprise one or more of the component elements of X, and optionally iii) one or more secondary carbon-containing materials; and        b) heating the resulting mixture at 100° C. to 1500° C. to yield the material comprising the X/hard carbon composite;
wherein X comprises one or more component elements selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel;
and wherein X is present in an amount of at least 5% by weight of the material comprising the X/hard carbon composite.
Very preferably, the one or more component elements of X are selected from: P, S, In, Sb, Sn, Pb and Ge.
The material comprising the X/hard carbon composite made by the process of the present invention comprises particles of X dispersed on the surface of a hard carbon core. However, the Applicant has found particular advantage when at least some of the component elements of X are located in the micro-sized pores of the hard carbon material; it is believed that this structure in particular will compensate for the volume expansion of the component elements of X and will give better long-term electrochemistry.
The material comprising the X/hard carbon composite made by the process of the present invention are useful anode materials for either sodium- or lithium-ion cells, but their use as anode materials for sodium-ion cells is particularly preferred.
A preferred feature of the present invention is that the average oxidation state of the one or more component elements of X in the one or more starting materials which comprise one or more of the component elements of X, is reduced during the process of the present invention. Preferably the reduction occurs during the heating step of the process. Thus, the average oxidation state of the one or more component elements of X in the X/hard carbon composite, is lower than the average oxidation state of the one or more component elements of X in the one or more starting materials which comprise one or more of the component elements of X. This reduction may be achieved by the reaction process being conducted in a reducing atmosphere (e.g. comprising carbon monoxide or hydrogen). Alternatively, it is desirable that the process of the present invention proceeds via a carbothermal-type reduction reaction which is facilitated by the reaction conditions, e.g. a non-oxidising atmosphere (such as nitrogen or argon), and the presence of the one or more secondary carbon-containing materials facilitate and/or the hard carbon starting material.
During a carbothermal-type reduction, the one or more component elements of X in the starting materials which comprise one or more of the component elements of X, are nucleated onto the carbon surface of the hard carbon-containing starting material. The result is a favourable X/hard carbon composite which has an intimate and uniform dispersion of the component elements of X in or on the pores of the hard carbon. The conductivity of the X/hard carbon composite is improved as a result of a network of finely divided component elements of X, preferably being deposited onto the carbon surface. The creation of multiple nucleation sites through the use of finely divided hard carbon also has the beneficial effect of minimizing grain growth of the X on the X/hard carbon composite. Further advantageously, the one or more secondary carbon material, promotes a carbo-thermal reaction which produces an even greater multitude of potential nucleation sites, and these, in turn, further minimize the grain growth of the component elements of X in the X/hard carbon composite. This is particularly the case when temperature conditions suitable to control particle size are also employed. The nucleation of the component elements of X onto the carbon surface is not able to occur in the case of the mechanical mixing methods that are employed in some of the prior art where the composite is simply a physical mixture of the components.
Thus, the process of the present invention will involve either the full or partial reduction of one or all of the one or more component elements of X, in the one or more starting materials which comprise one or more of the component elements of X. Preferably in the process of the present invention, one or more of the component elements of X in the one or more starting materials which comprise one or more of the component elements of X is reduced to oxidation state zero, or substantially zero, during the process of the present invention, preferably during the heating step. Further preferably, all of the one or more of the component elements of X in the X/hard carbon composite are in oxidation state zero or substantially zero.
Preferably, the one or more component elements of X in the X/hard carbon composite will be derived from the one or more starting materials which comprise one or more of the component elements of X.
Additionally or alternatively one or more of the component elements of X, in the X/hard carbon composite, are in compound form, for example with one or more secondary elements, preferably selected from: oxygen, carbon, nitrogen, phosphorus, sulfur, silicon, fluorine, chlorine, bromine and iodine. Further additionally or alternatively, the X/hard carbon composite, may comprise an alloy of two or more of the component elements of X.
In preferred material comprising an X/hard carbon composite made by the process of the present invention, X comprises one or more component elements selected from P, S, Sn, SnO, SnO2, Sb, Sb2O3, SnSb and SbO. Particularly preferred examples of materials comprising X/hard carbon composite made by the process of the present invention include: P/hard carbon, S/hard carbon, SnO/hard carbon, SnSnO/hard carbon, PSnO/hard carbon, SSnO/hard carbon, SbSb2O3/hard carbon, PSn/hard carbon, PSb/hard carbon and SnSb/hard carbon. In all cases X will be present in an amount of at least 5 wt % of the X/hard carbon composite.
In the process of the present invention the one or more starting materials which comprise one or more of the component elements of X are preferably in compound form, for example the starting materials can be oxides (e.g. Sb2O3, SnO2), carbonates (e.g. Sn2CO3), nitrates (e.g. Pb(NO3)2), phosphates or phosphides (e.g. Na2HPO2, H3PO4, AlPO4, InP), sulfates or sulfides (e.g. CoSO4, B2S3,), silicates (e.g. Sn(SiO3)2), halides (e.g. SnF4, SbCl3, BiBr3 and GeI4). The use of such starting materials in compound form, is in contrast to the use of an elemental form of X as a starting material by some of the prior art processes, and overcomes the difficulties caused by the low melting point of metals such as elemental tin.
However, in an alternative aspect, one or more of the starting materials may comprise one or more of the component elements of X in elemental form; this is particularly the case when X comprises phosphorus, i.e. phosphorus in elemental form is preferably used. When the component element of X in elemental form is used it may be coated with a coating material which, for example, is designed to prevent sintering during the heating step (b) of the process of the present invention.
Another advantage of the present invention is that it is possible to control the particle size of the one or more starting materials which comprise one or more of the component elements of X by for example milling the starting materials; this further assists in the production of uniformly dispersed small particulate X/hard carbon composite.
The process of the present invention employs a starting material for the hard carbon component of the X/hard carbon composite; the "hard carbon starting material". Such a hard carbon starting material may be any suitable carbon-containing material which is able to be converted to a hard carbon-containing material either during the process of the present invention, for example during the heating step b), or during a separate carbonization step. Such a suitable carbon-containing material (hard carbon starting material) may include, for example, an organic polymer (e.g. polyacrylonitrile or resorcinol-formaldehyde gel), glucose, sucrose, cellulose etc. The process of the present invention may alternatively employ a hard carbon starting material which already comprises hard carbon, for example because it has been pre-made prior to mixing with the one or more starting materials which comprise one or more of the component elements of X. In other words, the present process can use a hard carbon which is not made in situ as part of the process of the present invention, and as a result, its production does not rely on the in situ carbonization of a hard carbon starting material, Such pre-made hard carbon starting materials are conveniently available from commercial sources such as the Carbotron® hard carbon material (Kureha Corporation), or the Bio-Carbotron™ hard carbon material (Kuraray Chemical Company and Kureha Corporation). Alternatively, a proprietary Faradion hard carbon starting material with particularly advantageous structural characteristics can be easily made in a separate reaction prior to the process of the present invention, starting from a source of carbon such as sucrose-containing, or preferably a carbohydrate-containing material such as corn starch.
The preferred method to produce the proprietary Faradion pre-made hard carbon starting materials involves firstly heating a carbon source (e.g. sucrose or carbohydrate-containing material) at 220-240° C. for about 24 hours to dry it. Then the sample is ground to a particle size of about 20-30 μm using ball milling apparatus, followed by heating it under an inert atmosphere at a heating rate of about 5° C./min up to about 1200-1500° C., with a suitable dwell time to effect pyrolysis. Usually the dwell time is 2 hours. The resulting pyrolysed product is then recovered following cooling to room temperature, preferably at a rate of about 5° C./min.
Not only are the structural characteristics of a pre-made hard carbon starting material able to be controlled through the choice of carbon source and/or pyrolysis conditions, but its particle size can also be easily modified, for example by milling using suitable apparatus such as a planetary milling machine. Preferably, such pre-made hard carbon-containing starting materials can be milled to a particle size of 1 to 20 μm, preferably from 5 to 15 μm, ideally from 5 to 10 μm, and further ideally from 5 to less than 10 μm.
The first discharge specific capacity for hard carbon alone is generally under 200 mAh/g, but this value is too low to be of any real commercial value. The Applicant has advantageously found that materials comprising the X/carbon composite made by the present invention which contain at least 5 wt % of component X (as defined above) can significantly improve this first discharge specific capacity. Further, the Applicant has found that when the wt % amount of X in the composite is increased, further improvements in the first specific discharge capacity are also observed.
The first cycle efficiency is another useful measure of the commercial utility of an anode material. When hard carbon starting materials with a small particle size are used to provide the only source of hard carbon-containing in the anode material the first cycle efficiency is about 80-85%. However, the Applicant has surprisingly found that the materials comprising the X/hard carbon composite made by the process of the present invention show an efficiency over 90% when one or more secondary carbon-containing material is incorporated into the reaction mixture used in the process of the present invention. Preferred secondary carbon-containing materials include any carbon material with a BET nitrogen surface area of at least 5 m2/g, preferably at least 15 m2/g, advantageously at least 50 m2/g, ideally at least 62 m2/g and further ideally at least 500 m2/g.
Suitable example secondary carbon-containing materials include: activated carbon materials, particulate carbon black materials, graphene, carbon nano-tubes and graphite. Example particulate carbon black materials include: "C65™ carbon (also known as Super P® carbon black) (BET nitrogen surface area 62 m2/g) (available from Timcal Limited) although other carbon blacks are also available with a BET nitrogen surface area of <900 m2/g, for example "Ensaco® 350 g" which is a carbon black with a BET nitrogen surface area of 770 m2/g (available from Imerys Graphite and Carbon Limited as speciality carbons for rubber compositions). Carbon nano-tubes have a BET nitrogen surface area of 100-1000 m2/g, graphene around 2630 m2/g and activated carbon materials have a BET nitrogen surface area of >3000 m2/g.
As described above, the process of the present invention preferably involves at least the partial reduction of one or all of the one or more component elements of X, using one or both of the hard carbon starting material and the one or more secondary carbon-containing materials in a carbothermal reduction reaction. Ideally, in the process of the present invention, the amount of the one or more secondary carbon materials is sufficient to ensure that a maximum amount of carbon monoxide is generated during the reaction process, based on the amounts of the starting materials used. That is, the amount of one or more secondary carbon-containing materials is calculated such that it will all be oxidised to CO during the reduction reaction. Thus in this example, the final product (the material comprising an X/Hard carbon composite) will not contain any secondary carbon-containing material. For example: the amount of C65™ carbon added to the one or more starting materials which contain one or more component elements of X, e.g. Sb2O3 and SnO2, is determined according to the formulae below:Sb2O3+3C(C65™ carbon)→2Sb+3CO, andSnO2+2C(C65™ carbon)→Sn+2CO.
The present invention also preferably employs one or more secondary carbon materials in the reaction mixture, in an excess amount (i.e. in an over stoichiometric amount for the carbothermal reduction reaction), this is to ensure that at least a portion of the one or more secondary carbon-containing materials is present in the final material, i.e. X/secondary carbon-containing material/Hard carbon composite product. Useful examples include X/Graphite/Hard Carbon composite (which is expected to be useful for Li-ion applications), or as an X/hard carbon/C65™ carbon composite, or an X/Ensaco® 350 g/hard carbon composite.
In this way it is possible to make a highly conductive X/hard carbon composite in-situ during the synthesis step (b) of the present invention, which will improve the subsequent electrode performance. Moreover, an excess of one or more secondary carbon materials, will aid the morphology of the composite product. The one or more secondary carbon-containing materials present in the X/one or more secondary carbon-containing materials/Hard carbon composite will helpfully improve the composite's conductivity; and graphite is particularly useful at this because it is more conductive than C65™ carbon.
Preferably, the one or more secondary carbon material is chosen to the same carbon material which would conventionally be used in a subsequent process of electrode formulation. This will ensure that the number of constituents in the anode is kept to a minimum and that costs are controlled.
In another aspect therefore, the present invention provides a process for preparing a material comprising a X/secondary carbon-containing material/hard carbon composite comprising the steps:
a) forming a mixture comprising i) one or more starting materials for a hard carbon material, ii) one or more starting materials comprising one or more of the component elements of X, and iii) an excess of one or more secondary carbon materials; and
b) heating the resulting mixture to yield an X/secondary carbon/hard carbon composite; wherein X comprises one or more component elements selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel; and
wherein X is present in an amount of at least 5 wt % in the X/secondary carbon-containing material/hard carbon composite.
Preferably, the average oxidation state of the one or more component elements of X in the X/secondary carbon-containing material/hard carbon composite is lower than the average oxidation state of the one or more component elements of X in the one or more starting materials comprising one or more of the component elements of X.
The present invention therefore provides material comprising an X/hard carbon composite, comprising one or more hard carbon materials, one or more component elements of X and one of more secondary carbon-containing materials.
The one or more hard carbons, the one or more component elements of X and the one or more secondary carbon-containing materials are the same as those described above.
Advantageously, the use of a Sn-containing compound (such as SnO2) as the starting material comprising the component elements of X, avoids the issue of dealing with the handling problems caused by tin metal having a melting point of 231.9° C.
Unlike some of the prior art processes described above, the process of the present invention may be easily adapted to produce commercial quantities of material comprising X/hard carbon composite (10-1000 kg/batch), at low cost and using a simple continuous production process. Moreover, the X/hard carbon composite-containing material is recoverable at the end of the process of the present invention without the need for purification prior to being used in anode production.
As discussed above, step a) in the process of the present invention involves forming a mixture comprising i) one or more hard carbon starting materials, ii) one or more starting materials which comprise one or more of the component elements of X, and optionally iii) one or more secondary carbon-containing materials. Mixing is conveniently achieved using a planetary mill and the starting materials i), ii) and optionally iii), can be mixed together in any order and in any combination. Preferably, the one or more hard carbon starting materials and the one or more starting materials which comprise one or more of the component elements of X are dry mixed in a planetary milling machine for at least 5 minutes, preferably for 5 minutes to 12 hours and typically for 30 minutes, at a speed of 100 rpm to 800 rpm, desirably at a speed of 250 to 350 rpm and typically at a speed of 300 rpm.
Two typical mixing regimes for step (a) of the process of the present invention are described as follows:                1) Starting materials: one or more hard carbon starting materials, one or more starting materials which comprise one or more of the component elements of X (e.g. Sb2O3 or SnO2) and optionally one or more secondary carbon-containing materials.                    Mixing method: dry mixing all of the starting materials together in a single step using planetary mill for 30 mins at a speed of about 300 rpm.                        2) Starting materials: one or more hard carbon starting materials, one or more starting materials which comprise one or more of the component elements of X (e.g. Sb2O3 or SnO2) and one or more secondary carbon-containing materials                    Mixing method: the starting materials are dry mixed in a two-step process.            Step i): one or more starting materials which comprise one or more of the component elements of X (e.g. Sb2O3 or SnO2) and the one or more secondary carbon-containing materials are dry mixed using planetary mill for 4 hrs at a speed of about 300 rpm.            Step ii): one or more hard carbon starting materials are then added to the mixture from step i) and dry mixed using a planetary mill for 30 mins at about 300 rpm.
Step (b) of the process of the present invention involves heating the mixture resulting from step (a), in either a non-oxidising or a reducing atmosphere to yield an X/hard carbon composite. The temperature and chosen atmosphere will facilitate at least a partial reduction of some or all of the one or more component elements of X in the X/hard carbon composite. The precise temperature used will differ depending on the particular choice of reactants, but it is important that the heating temperature is, on the one hand, high enough to ensure the at least partial reduction of the one or more of the component elements of X in the starting material, and on the other hand is not so high that it encourages the particle size of the components of X in the X/hard carbon composite to grow too large, because this causes problems as discussed below.
The heating temperature in heating step (b) is typically performed either at a single temperature or over a range of temperatures and is in the range 100 to 1500, preferably 100 to 850° C. preferably 100 to 700° C., yet further preferably 200 to 600° C., advantageously 200 to 695° C. and ideally 200 to 590° C. The typical temperature used tends towards 100 to 700° C., when one or more secondary carbon-containing materials are present in the reaction mixture. The duration of heating is for as long as is necessary for the one or more component elements of X to be at least partially reduced. Typically the heating step is performed for up to 10 hours, preferably up to 8 hours, further preferably up to 4 hours and ideally up to 2.5 hours.
It is highly desirable to use the minimum temperature and shortest dwell time when carrying out the process of the present invention because the particles of X will grow at high temperatures, and the higher the temperature used in heating step b) the quicker the particles of X will grow. Also, the grain size of X will increase as the dwell time increases. If the grain size of X is not controlled within the desired size limits then the resulting X/hard carbon composite is found to exhibit poor electrochemical behaviour when used as an anode material. Preferably, therefore the particles of X in the resulting X/hard carbon composite have a particle size, which can be determined by microscopy, of no larger than 20 μm, most preferably no larger than 15 μm, and ideally in the range 0.1 to 10 μm.
The particle size of the hard carbon in the x/hard carbon composite is typically 1 to 20 μm and preferably between 5 and 10 μm. The preferred size of the X/hard carbon composite particle is in the region of 10 μm.
The heating step (b) is readily conducted in a tube furnace. The most favourable temperature range for a particular one or more starting materials which comprise one or more of the component elements of X is conveniently determined by forming the starting material mixture as described above, heating it through a sequence of individual temperatures from low to high temperature and observing the effect that each temperature has on the starting material mixture, using XRD analysis. From these tests it is possible to determine at which temperature the starting materials (e.g. Sb2O3 or SnO2) are fully reduced to the respective metals (e.g. Sb and Sn) or partially reduced to the respective compounds (e.g. SbO2 and SnO).
A non-oxidizing atmosphere is conveniently provided by a static or flowing stream of a non-oxidising gas such as nitrogen or argon and a reducing atmosphere is conveniently provided by a static or flowing stream of a reducing gas such as hydrogen or carbon monoxide.
The general method of the present invention involves a step (a) during which i) the one or more hard carbon starting materials, ii) the one or more starting materials which comprise one or more of the component elements of X, and optionally iii) the one or more secondary carbon-containing materials, are mixed together, preferably using one of the planetary milling methods described above, and the resulting milled starting material mixture is then placed into any suitable reaction vessel, for example an alumina crucible. The filled crucible is then put into a tube furnace, preferably under a non-oxidizing atmosphere, and the milled starting material mixture is heated per the heating step (b). Preferably the rate of heating is reasonably slow, for example 2 to 5° C./min, and once at the desired temperature there follows a dwell period of up to 6 hours, before the reaction mixture is cooled, for example at a rate of 5 to 10° C./minute, to form the resulting X/hard carbon composite.
The required ratio of the starting materials present in the reaction vessel prior to the heating step (b) (i.e. the one or more starting materials which comprise one or more of the component elements of X:one or more hard carbon starting materials:one or more secondary carbon-containing materials) will be determined by back calculating from the amount of reducing agent that will need to be produced to yield the desired product composition.
For example, when a 10 wt % Sb/hard carbon composite is desired, the starting materials will need to be present in the following amounts:
Secondary carbon material=1.4 wt %;
Starting material comprising one or more of the composite elements of X, Sb2O3=11.6 wt %
and
hard carbon starting material=87.0 wt %
Final ratios in the X/hard carbon composite: Sb=10 wt %, hard carbon=90 wt %
When a 30 wt % Sb/hard carbon composite is desired, the starting materials will need to be present in the following amounts:
Secondary carbon material=4.0 wt %;
Starting material comprising one or more of the composite elements of X, Sb2O3=32.5 wt %;
and hard carbon-containing starting material=63.5 wt %
Final ratios in the X/hard carbon composite: Sb=10 wt %, hard carbon=90 wt %
When a 10 wt % Sn/hard carbon composite is desired the starting materials will need to be present in the following amounts:
Secondary carbon=2.0 wt %;
Starting material comprising one or more of the composite elements of X, SnO2=12.0 wt %;
and
hard carbon starting material=86.0 wt %
Final ratios in the X/hard carbon composite: Sn=10 wt %, hard carbon=90 wt %
When a 30 wt % Sn/hard carbon composite is desired the starting materials will need to be present in the following amounts:
Secondary carbon=5.3 wt %;
Starting material comprising one or more of the composite elements of X, SnO2=33.5 wt %;
and
hard carbon starting material=61.2 wt %
Final ratios in the X/hard carbon composite: Sn=30 wt %, hard carbon=70 wt %
The amount of X in the X/hard carbon composite is at least 5% by weight of the X/hard carbon composite or the X/secondary carbon-containing material/hard carbon composite; preferably the amount of X is from 5% to 90% by weight, further preferably from 5% to less than 70% by weight, advantageously 8% to 65% by weight, and from 10% to 30% by weight is especially preferred.
The process of the present invention provides many advantages over the methods described in the prior art. Firstly, it is possible independently to control the particle size of the X/hard carbon composite and/or the grain size of X and/or the hard carbon in the X/hard carbon composite and the X:carbon ratio, by: i) milling the starting materials; ii) varying the heating temperature used in step (b) of the process, iii) altering the duration of the heating step (b), e.g. by altering the dwell time, and iv) by varying the additives used in the starting material mixture.
The process of the resent invention allows for benefit to be obtained as a result of the many different properties of the hard carbon and/or the one or more secondary carbon-containing materials, for example as a reductant, as a material which can absorb/adsorb sodium, as a dispersant for X, and as a material for maintaining X in a fixed location.
In a second embodiment, the present invention provides a material comprising a X/hard carbon composite wherein X comprises one or more selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel, in elemental and/or compound form; wherein X is present in an amount of at least 5% of the X/hard carbon composite.
Preferably, the material according to the present invention comprises an X/hard carbon composite wherein X comprises one or more selected from Sb, Sn, P, S, In, Pb and Ge, in elemental and/or compound form; wherein X is present in an amount of at least 5% of the X/hard carbon composite.
Preferably, the elemental components of X are located on the outer surface of the hard carbon material, and/or within the micro-size pores in surface of the hard carbon material.
In the X/hard carbon composite it is preferred that when X comprises Sn or a SnSb alloy, particles of Sn or SnSb alloy are only located within the micro-size pores in the surface of the hard carbon material.
Further the present invention provides a material comprising a X/one or more secondary carbon-containing material/hard carbon composite-containing materials, wherein X comprises one or more selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel, in elemental and/or compound form; wherein X is present in an amount of at least 5% of the X/one or more secondary carbon-containing material/hard carbon composite.
In addition, the present invention provides material comprising an X/hard carbon composite obtained by the process according to the present invention, wherein X comprises one or more selected from antimony, tin, phosphorus, sulfur, boron, aluminium, gallium, indium, germanium, lead, arsenic, bismuth, titanium, molybdenum, selenium, tellurium, cobalt and nickel in elemental and/or compound form; and wherein X is present in an amount of at least 5% of the X/hard carbon composite.
Preferably, the elemental components of X are located on the outer surface of the hard carbon material, and/or within the micro-size pores in surface of the hard carbon material.
Further, the present invention provides comprising an X/one or more secondary carbon-containing materials/hard carbon composite obtained by the process according to the present invention.
The reaction process of the present invention is preferably performed in the solid state, which in this context is to be interpreted as being in the absence of a solvent or other liquid, or substantially in the absence of a solvent or other liquid, during the heating step (b). For this purpose it is advantageous if the starting materials (the one or more hard carbon starting materials and the one or more starting materials comprising one or more of the component elements of X, and the one or more secondary carbon-containing materials) are mixed together in solid form. It is, however, possible that the starting materials may be combined with a mixing liquid to aid milling and/or to aid in the formation of the mixture of starting materials in step (a), however, this mixing liquid is preferably removed or at least substantially removed, for example by evaporation, carried out at room temperature or at an elevated temperature, optionally under a partial vacuum, prior to the heating step (b). One or more of the starting materials may also be dispersed or dissolved in a fluid (liquid or gas) in step (a).
Advantageously, the materials comprising an X/hard carbon composite made according to the process of the present invention may be used in a negative electrode (anode), in conjunction with a counter electrode and one or more electrolyte materials. The electrolyte materials may be any conventional or known materials and may comprise either aqueous electrolyte(s) or non-aqueous electrolyte(s).
Anode electrodes that comprise materials comprising one or more X/hard carbon composites made according to the present invention are suitable for use in many different applications including sodium ion and/or lithium ion and/or potassium ion cells which may be widely used for example in energy storage devices, such as batteries, rechargeable batteries, electrochemical devices and electrochromic devices.
In a further aspect of the present invention, there is provided a process for preparing X/hard carbon composite using a carbo-thermal reduction reaction.

X/hard carbon composite material and method of preparing the x/hard carbon composite material


A weaving machine including a machine frame, an apparatus for supplying warp threads, a support apparatus, a plurality of heald frames, a reed, and a replaceable changing apparatus releasably connectable with the machine frame or the support apparatus and including at least one whip roll for deflecting the warp threads, a warp stop motion unit, a holder device for the heald frames and the reed, and at least one apparatus for guiding and/or fixing the warp threads.

1. Field of the Invention
The invention relates to a weaving machine, in particular a narrow fabric weaving machine, comprising a machine frame, an apparatus for the supply of warp threads, at least one whip roll for the deflection of the warp threads, a support apparatus, a warp stop motion unit, a plurality of heald frames, and a reed.
2. Description of the Prior Art
In order to be able to make a change after the warp and/or the article to be produced has run out, care must be taken that the warp threads do not become mutually entangled. For this reason, it is known, on the one hand, to use a divided weaving machine or to replace the entire weaving machine and, on the other hand, to use a mobile apparatus and/or a storage carriage, with the warp stop motion, the heald frames and the reed generally being taken out and put in together, and with attention being paid to the warp threads remaining taut.
It proves disadvantageous in this respect that the replacement of a weaving machine or of a weaving machine part is laborious and that the whip roll remains in the weaving machine in the case of mobile apparatuses so that measures must be taken in order that the position of the warp threads and the tension in the warp threads is maintained. This means a greater amount of labor for a change of warp and/or article.
For narrow fabric weaving machines an installation apparatus is known by means of which the heddles of the heald frame are stripped off out of the heddle guide rod transverse to the direction in which the band runs and in the horizontal direction in order to perform a change of article. This change is very difficult and laborious to perform. In addition, the time required is considerable.
Accordingly an object of the present invention is to provide a weaving machine in which a change of warp and/or article can be carried out with simplified means and with the lowest time requirement.

Mechanical loom with warp changing apparatus


A current sense circuit with fast response for sensing a current input from a current source such as a memory cell, comprising a first amplifying means and a second amplifying means coupled to a first transistor and a second transistor, respectively. The first transistor is smaller in size than the second transistor and the reference voltage of the first amplifying means is slightly larger than the reference voltage of the second amplifying means. A load is coupled to the drain of the first transistor.

The present invention relates to a current sense circuit for sensing memory devices, and more particularly, to a circuit suitable for fast response operations of large signals.
The current sense circuit is as well known, good for sensing small currents from signal sources which have large inherent capacitances. This is because the current sense circuit has a low input impedance and can provide a constant voltage for the signal source. By means of providing a constant voltage across the inherent capacitance of the signal source, it can avoid current being contributed by the capacitance so that the true signal current can be picked up by the sense circuit.
One of the conventional current sense circuits is as shown in FIG. 6 which comprises a current source type input to the sense circuit at 14', an impedance transfer circuit 17' composed of a sense transistor M1 and an inverting amplifier A1, a load 21' connected between the drain of the transistor M1 and a positive supply terminal Vcc and a two-stage comparator 23'. The output 19' of the impedance transfer circuit 17' is coupled to the inverting terminal of the two-stage comparator 23' so as to be compared with a first reference voltage 22' which inputs from a non-inverting terminal of the comparator 23'.
The current source input 14' is coupled to an inverting terminal of the amplifier A1 and a second reference voltage 18' is input to the amplifier A1 from a non-inverting terminal thereof. The transistor M1 is served as a source follower. The output of the amplifier A1 is connected to a gate of the transistor M1 and there is a negative feedback loop between the amplifier and the transistor so that at the point 15', there is a very low input impedance and a constant terminal voltage, which approximately equals the second reference voltage 18' that is provided. In a real circuit, the amplifier A1 may be an amplifier with a single input terminal. In this case, the reference voltage 18' is deemed as a virtual reference voltage.
The impedance transfer circuit 17' has a high impedance output on the point 19' and the current at the point 19' equals the current flowing to the current source input 14'. Therefore, by measuring the current at the point 19', it is possible to measure the current of the current source 14'. The comparator 23' then compares the current level (or voltage level output Vout) and the first reference current level (or the first reference voltage level 22') to provide a logic level output 24' for the sense circuit.
However, when the prior sense circuit is applied to sense the current of the memory devices, several problems occur. In such case, the current source 14' is a memory cell and the sense circuit will be influenced not only by the small signal response, but also by the large signal response. Such a prior sense circuit is normally connected to the memory cell via bit line multiplexers and bit lines and the selected bit lines should undergo voltage level transition caused by the action of an address decoder. In the transition period, the current sense circuit of FIG. 6 can pick up combinations of signals, especially the current contribution of the inherent capacitance of the signal source, rather than the true signal current. In this case, the inherent capacitance of the signal source is a parasitic capacitance of the bit line and the current picked up by the sense circuit is mostly the charge current for the parasitic capacitance, which is much larger than the true signal current which the circuit intends to detect.
To explain the disadvantages of the prior art, the following discloses a conventional read only memory cell array and multiplexer in accompanied with FIG. 5.
As shown in FIG. 5, the memory cell array includes word lines 5, bit lines 6 and a number of cell transistors such as those 1, 2, 3 and 4. The multiplex includes X multiplexers 7, 8 and Y multiplexers 9, 10, 11 and 12. The arrow numbered by 14 in FIG. 5 connects to the current source 14' in FIG. 6 (14" in FIGS. 8 and 14 in FIG. 1) representing that the output of the memory cell are input into the current sense circuit. Each of the cell transistors represent some bit of data. Take the cell transistor 3 as an example, if the transistor 3 is a normal transistor, the bit is 1 and if the transistor is an always-off transistor (e.g. by means of being programmed by boron implantation), the bit is 0. To access the bit represented by the transistor 3, XA 7 is set to low, XB 8 is set to high; WO2 5 is set to high, other word lines 5 except WO2 are set to low; YM1 is set to high, YG1 is set to high, and YG2 is set to low. In this way, BL2 (a second bit line) and source/drain diffusions S2B and S3A are switched to the terminal 14; BL3 (a third bit line) and source/drain diffusion S3B are switched to ground; BL1 (a first bit line) and source/drain diffusion S2A are switched to the terminal 13.
In order to determine whether the transistor 3 is a normal transistor or an always-off transistor, the sense circuit provides a bit line voltage of 1.5 V to the bit line, hence a voltage of 1.5 V shall be applied to the transistor at S3A. At this time, S3B is connected to the ground. If the transistor 3 is a normal transistor, it will be turned on and a current will flow therefrom. If the transistor 3 is an always-off transistor, then no current will be flowing from the transistor 3. Accordingly, the sense circuit is used to detect and quantize the current level into logic 1 or 0. In the case of the above, since BL1 and S2A are driven to 1.5 V via the terminal 13, no current will pass through the transistor 1, that is, only the transistor 3 is tested.
The equivalent circuit or the memory cell which connects to a normal transistor is as shown in FIG. 7 which comprises a cell current source Ic and a stray capacitance C.sub.O and a resistance R.sub.O respectively connected in parallel with the cell current source Ic. If the memory cell is connected to an always-off transistor cell, the equivalent circuit of the memory cell can be obtained by removing the elements R.sub.O and I.sub.c from FIG. 7, which means that the equivalent circuit thereof is equivalent to the bit line stray capacitance C.sub.O. For fast detection, the voltage of selected bit line has to be increased to a higher potential of about 1.5 V from ground potential. When an always-off transistor is used, the charge of the bit line capacitance will dominate the current being picked up by the sense amplifier, such that the correct data is unavailable. Moreover, in order to achieve faster access time for the memory chip, the transition time of the bit line should be as short as possible. However, due to the presence of the load 21' as shown in FIG. 6, the access time is limited. As a result, the sense circuit in FIG. 6 is not suitable for fast operation with bit line voltage transition.
Another prior art of the sense circuits which is intended to solve the problem of the load by restricting the response of the large signals (i.e., the voltage of the bit line range from 0 to 1.5 V) is as shown in FIG. 8. To help to explain the operation of the sense circuit of FIG. 8, the same elements as those shown in FIG. 6 are referenced by the same numbers. As shown in the figure, the circuit further comprises a second transistor M2 disposed between the inverting amplifier A1 and the transistor M1. Further, a Miller's capacitance C.sub.m is connected between a gate of the second transistor M2 and a drain of the first transistor and a stray capacitance C.sub.L is connected between the drain of the first transistor M1 and a ground. The source of the transistor M2 is connected to the connecting point of the source of the transistor M1 and the current source 14" for speeding up the response of the large signals. In the case of detecting small signals, part of the current from the current source 14" bypasses through the transistor M2 such that the current I1 in FIG. 8 is smaller than that in FIG. 6. When the current I1 becomes smaller, the voltage drop across the load 21" decreases, thereby limiting the voltage martin of the sense circuit. During operation, current I1 and current I1 are switched on simultaneously and the current I2 is large than I1, so that if the load 21" does not become larger, the sense margin will become smaller. By increasing the impedance of the load 21", the sensing margin will be retained, it will cause the following disadvantages:
(1) The higher the impedance of the load 21" is the larger the voltage gain from terminal 14" to the output terminal 19" becomes, the noise immunity becomes poorer, which results in an unstable operation point of the transistor M1; and PA1 (2) The higher the impedance of the load 21" is, the smaller the current I1 through the load becomes, thus inevitably causing the small signal response to slow down.
The current through the transistor M2 can be compensated by enlarging the size of the transistor M2, but the larger the transistor M1 is, the larger the Miller's capacitance C.sub.m becomes, and hence the stray capacitance C.sub.L will be, which further degrades the response speed of the small signals.

Current sense circuit with fast response


An antenna comprises electrical conductors arranged to form a radiating element including a folded line configuration and a distributed strip configuration, where the radiating element can be in proximity to a ground conductor and/or arranged as a dipole. Embodiments of the antenna include conductor patterns formed on a printed wiring board, having a ground plane, spacedly adjacent to and coplanar with the radiating element. An antenna can comprise a distributed strip patterned on a printed wiring board, integrated with electronic components mounted on top of or below the distributed strip, and substantially within the extents of the distributed strip. Mounting of electronic components on top of or below the distributed strip has little effect on the performance of the antenna, and allows for realizing the combination of the antenna and integrated components in a compact form. An embodiment of the invention comprises an antenna including a distributed strip, integrated with a battery mounted on the distributed strip.

Wireless communication systems operating at radio frequencies and having antennas, are demanding ever smaller form factors, as for example, in the field of radio frequency identification (RFID). RFID allows users to identify, locate, track and exchange information with remote assets. Typically in RFID applications a wireless communication device containing data, and including an antenna and a microchip and/or a surface acoustic wave (SAW) device, is attached to the item to be identified or tracked while a "host" reads and/or writes information to the device through the use of radio frequency communication. Applications for this technology are rapidly expanding across a range of economic sectors that include manufacturing, retail, medical care, agriculture, transportation and environmental stewardship. In all these applications, compact low-profile RFID devices are highly valued, making reduced antenna size an area of great interest and endeavor.
Device size is an issue in wireless systems. Small devices are more easily sorted, transported and/or used. Typically, a compact or low-profile wireless device is more desirable, and sells at a higher price than an equivalent but larger device would. Unfortunately there are components that are found within all portable wireless devices that are not easily miniaturized, for example, batteries and antennas.

Antenna with distributed strip and integrated electronic components


A system and method for asset tracking and monitoring using antenna diversity. Antenna diversity ensures that the mobile terminal maintains good visibility of a satellite throughout the transport route. In one example, a first antenna is mounted on a first side of an asset transporter (e.g., flatbed trailer) and a second antenna is mounted on a second side of the asset transporter. A selector/combiner in the mobile terminal enables multiple antennas to be leveraged in the satellite communication process.

1. Field of the Invention
The present invention relates generally to tracking and monitoring and, more particularly, to a system and method for asset tracking and monitoring using antenna diversity.
2. Introduction
Tracking mobile assets represents a growing enterprise as companies seek increased visibility into the status of movable assets (e.g., trailers, containers, etc.). Visibility into the status of movable assets can be gained through mobile terminals that are affixed to the assets. These mobile terminals can be designed to generate position information that can be used to update status reports that are provided to customer representatives.
In a conventional tracking system, the mobile terminal is affixed to the roof of the trailer. This location of attachment ensures that the satellite receiver in the mobile terminal maintains good visibility throughout the transport route. In some asset transporters (e.g., flatbed trailer), the potential points of attachment of the mobile terminal are limited. For example, the mobile terminal may be attached to one side of the flatbed trailer. This attachment option is not ideal, however, because the load can obscure the visibility of the mobile terminal to the satellite. What is needed therefore is a mechanism that increases the quality of transmission/reception of mobile terminals that are affixed to asset transport systems that have limited points of attachment.

System and method for asset tracking and monitoring using antenna diversity


A pneumatic spinning apparatus comprises a nozzle block having a nozzle which gives a whirling air stream to a fiber bundle coming out of the draft device, a spindle having a fiber bundle passage, a guide member with its forward end protruding into a spindle inlet port, and an introduction tube having a fiber bundle passage which has been separated into a plurality of parts and fixed at the nozzle block inlet side.

1. Field of the Invention
The present invention relates to an apparatus for manufacturing a spun yarn by twisting an untwisted fiber bundle drafted by a drafting device, by applying a whirling stream of air to the fiber bundle, and more particularly, to a spinning apparatus for a bundle of long fibers.
2. Prior Art
An apparatus for producing a real twisted yarn wherein a guide member is provided within a nozzle block for exerting a turning air stream on a fiber bundle moved out of a drafting device with an extreme end thereof directed at an inlet of a rotating or stationary spindle is known by Japanese Patent Provisional Publication No. 161525/1991.
In the apparatus for producing a real twisted yarn constructed as described above, the fiber bundle moved out of the drafting device is attracted into the nozzle block and exposed to a turning stream in the vicinity of the inlet of the spindle and slightly twisted. At this time, all the fibers of the fiber bundle are positioned in the periphery of the guide member and directly exposed to an air flow to receive a force separating from the fiber bundle. However, since the extreme end of the fiber positioned at the inlet of the spindle is subjected to twisting, it is not easily separated. The separated rear end of the fiber is wound about the outer periphery of the spindle and extends outwardly. The fiber is gradually drawn while turning about the fiber bundle as the fiber bundle runs, and most fibers are spirally wound to form a real twist-like spun yarn.
The spinning apparatus described above is an excellent apparatus capable of manufacturing ring-twisted yarns of high quality both in appearance and strength characteristics because of an extremely large quantity of wound fiber. For spinning a long fiber such as wool, a spun yarn bundle, as shown in FIG. 8, which has much core fiber and little wound fiber is produced, due particularly in the case of wool to a long and thick fiber and a small number of component fibers in yarn.
In a general cotton yarn, the mean length of the short fibers is in the range of 23-25 mm and the number of short fibers constituting a cotton yarn having an Ne. of 30 is relatively large (on the order of about 100). On the other hand, in a wool yarn, the mean length of the long fibers is in the range of 60-80 mm, and the number of fibers constituting a wool yarn having an Ne. of 30 is relatively smaller (on the order of about 40).
Accordingly, if the long fiber bundle is spun using a known spinning device for a short fiber bundle, a bundled spun yarn as shown in FIG. 8, in which there are less wound fibers, is produced since separation of fibers can not be accomplished adequately and the number of fibers which are constituting wound fibers of a spun yarn is less.

Introduction device for a spinning apparatus


A method and apparatus for indicating when a device in a computer system is communicating with memory. Information is communicated between the device and memory in a manner that bypasses a bus. A side-band signal that indicates that this communication is transpiring is sent to a second device connected to the second bus. In response to this side-band signal, a bit in a register of the second device is set to a value that is then communicated by way of the second bus.

As computer systems get faster and more powerful they tend to consume more electricity. This makes operation of these computer systems more expensive. In addition, the increase in energy consumption of these computers tends to result in an increase in heat generated by the computers. If not properly dissipated, this heat can impede operation or even destroy the computer. Therefore, energy consumption and heat dissipation is a concern in the design of most computer systems.
Mobile computer systems represent a particular concern to system designers because mobile computer systems are typically powered by a battery, significantly limiting the amount of electrical energy available to the computer. In addition, because mobile computer systems must remain lightweight to be attractive to the consumer, the range of heat dissipation devices available to the system designer for cooling the computer is severely limited by the weight constraints. Mobile computers include, for example, laptop, notebook, sub-notebook, handheld, and other portable computers and personal data assistants.
A computer system contains one or more processors along with other electronic devices that communicate with the processor. A processor is typically considered to be the "brain" of the computer system, and generally consumes the most amount of energy. Because the processor typically consumes the most energy of all the devices in a system, most energy consumption reduction efforts focus on the processor. One method of reducing energy consumption is to place the processor into a low power state during which time one or more of the many functions performed by the processor are essentially disabled. Each function performed by the processor consumes some portion of the total energy consumed by the whole, so by disabling one or more functions of the processor, the overall energy consumption of the processor is reduced. A low power state is also referred to as sleep, deep sleep, throttle, and power-down.
Before disabling any functions of the processor, however, it is first determined whether or not the function being disabled is needed by any of the other electronic devices of the computer system. If the function is needed, then that function cannot be disabled. For example, one function performed by the processor is making sure that the information stored in the processor's local memory, or cache, is consistent with the information stored in the main memory of the computer system. Ensuring consistency between data in the cache and data in other memory locations is known as maintaining cache coherency. Some low power states are non-coherent low power states in that they don't support cache coherency. If one attempted to place the processor into a low power state that doesn't support cache coherency, the system would need to first check to ensure that none of the other electronic devices are communicating with main memory at the time.
If any of the devices are communicating with main memory when the processor attempts to transition to a non-coherent low power state, there exists the danger that the device will change data stored in main memory, thereby making the data inconsistent with copies of the data stored in the processor's cache. To eliminate this danger, the transition to a low power state is prevented if it is determined that an electronic device is in communication with main memory. Electronic devices that can initiate communication with main memory are called bus masters because they are capable of mastering, or gaining ownership of, the bus or buses necessary to communicate with slave or target devices such as memory.
To determine whether or not any bus masters are communicating with main memory, the processor must poll, or read information from, the masters to determine the status of the masters. If a master is communicating with main memory, or other memory location in the computer system, the master, or other control device, notifies the processor of this activity in response to being polled. Unfortunately, as more masters are added to the computer system, the processor must take the time to poll more devices before determining whether or not it is safe to transition to a low power state that fails to support cache coherency. This delays the transition to the low power state and increases the amount of communication between devices in the computer system. As a result, power consumption increases, as does the burden on software to coordinate all of this polling activity.

Method and apparatus for indication when a bus master is communicating with memory


The yield of a sealing process for a semiconductor device which adopts a flip-chip mounting method is to be improved. In a molding process wherein plural semiconductor chip ICs mounted on a parts mounting surface of a substrate matrix through bump electrodes are to be sealed all together with a sealing resin in a reduced state of the internal pressure of a cavity of a molding apparatus, a clamping pressure at the time of clamping the substrate matrix by both a lower die and an upper die of a molding die is set at a relatively low pressure in an initial stage of injection of the sealing resin and is changed to a relatively high pressure when the sealing resin has covered the semiconductor chip ICs located in a final stage in the resin injecting direction.

The present invention relates to a semiconductor device manufacturing method and a semiconductor device technique. Particularly, the present invention is concerned with a technique applicable effectively to a resin sealing technique for a semiconductor device which adopts a flip-chip mounting method.
The flip-chip mounting method is one of mounting methods for mounting a semiconductor chip onto a wiring substrate through bump electrodes (protrude electrodes). In connection with the flip-chip mounting method, as a method for injecting resin into the gap between a semiconductor chip and a wiring board, there is known a method wherein liquid resin is added dropwise to a part of the outer periphery of the semiconductor chip and the resin, in a softened state by heating, is penetrated into the gap between the semiconductor chip and the wiring substrate by utilizing the capillary phenomenon. According to this method, however, since the injection of resin is performed for each semiconductor chip, it takes time for the injection of resin and thus the productivity is low; besides, the resin itself is expensive, resulting in that the cost of the semiconductor device becomes high.
On the other hand, as a semiconductor chip sealing method, there is known an MAP (Mold Array Package) method wherein plural semiconductor chips are mounted on a wiring substrate, then are covered all together with a sealing resin, and are then cut out into individual semiconductor chips. According to this method, since plural semiconductor chips can be sealed all together, it is possible to shorten the sealing time and improve the productivity of semiconductor devices. Besides, the cost of the sealing material itself is about one tenths of that in the foregoing known method and is thus much lower. Consequently, it is possible to reduce the cost of each semiconductor device manufactured.
However, if the above MAP method is adopted in the flip-chip mounting method, since the gap between the semiconductor chip and the wiring substrate is narrow, the sealing resin cannot sufficiently be injected into the gap, thus giving rise to the problem that voids are formed. If voids are formed due to insufficient injection of the sealing resin into the gap between the semiconductor chip and the wiring substrate, there arise the problem that mutually adjacent bump electrodes melt at the time of heat treatment after the sealing step and are short-circuited through the voids and the problem that the bump electrodes are apt to be disconnected due to deformation of the wiring substrate and a sealing body caused by a temperature cycle after the sealing step.
A countermeasure to the formation of such voids in the semiconductor device which adopts the flip-chip mounting method is described in, for example, Japanese Unexamined Patent Publication No. Hei 11(1999)-121488. It is described therein that the interior of a molding die cavity is brought into a state of reduced pressure in a resin sealing step, whereby a sealing resin can be injected uniformly into the gap between a semiconductor chip and a wiring substrate (see Patent Literature 1). Further, for example in Japanese Unexamined Patent Publication No. 2001-135658 it is described that, by reducing the internal pressure of a molding die cavity in a resin sealing step, molten resin can be injected stably into the whole of the interior of the cavity while suppressing the formation of voids (see Patent Literature 2).
[Patent Literature 1]
Japanese Unexamined Patent Publication Hei 11(1999)-121488
[Patent Literature 2]
Japanese Unexamined Patent Publication No. 2001-135658
However, the present inventor has found out that the following problem is involved in the technique of reducing the internal pressure of a molding die cavity when sealing resin in the semiconductor device which adopts the flip-chip mounting method.
In the above Patent Literatures 1 and 2, a thorough consideration is not given to the occurrence of variations in thickness of wiring substrates. In an actual resin sealing step for a semiconductor device which adopts the flip-chip mounting method, even if the interior of a molding die cavity is brought into a state of reduced pressure, sealing resin cannot sufficiently be injected to the back side of the semiconductor chip lying within the cavity, especially into the gap between the semiconductor chip and the wiring substrate used, and voids may occur.
At present, molding dies are designed on the assumption that a lead frame is used as a semiconductor chip mounting member. Lead frames are almost constant in thickness, while wiring substrates vary in thickness with an increase in the number of constituent layers, and the range of error is also becoming larger. Sealing resin is injected into a cavity of a molding die while a part of a wiring substrate is crushed by the molding die lest the sealing resin should leak from the cavity in a sealing step. However, if the thickness of the wiring substrate placed within the molding die is larger than a preset value although it is within a tolerance, the proportion of the crushed portion of the wiring substrate becomes larger than a preset value and hence air vents in the molding die are closed with a portion of the wiring substrate. As a result, it becomes impossible to let the gas present within the cavity escape sufficiently to the exterior, thus giving rise to the problem that voids are formed. Especially in the case of the flip-chip mounting method, the problem of voids is apt to occur because the gap between the semiconductor chip and the wiring substrate is very narrow and tends to become still narrower. On the other hand, if the thickness of the wiring substrate placed within the molding die is smaller than the preset value although it is within the tolerance, the proportion of the crushed portion of the wiring substrate becomes excessively smaller than the preset value, so that the openings of air vents become larger than necessary, with consequent leakage of the sealing resin to the exterior from the air vents. Once the sealing resin leaks to an outer frame of the wiring substrate, it becomes impossible to effect automatic conveyance, thus giving rise to the problem that the yield and productivity in manufacturing the semiconductor device are deteriorated.

Manufacturing method of a semiconductor device


When a driver operates an activation switch, an electric parking brake apparatus performs a parking brake activation control in order to operate an electric motor until the tension of a base wire reaches a predetermined target tension to thereby bring parking brakes into an activated state. After that, the apparatus again performs the parking brake activation control when a re-activation time, which is set in accordance with the difference between an estimated temperature of a service brake and an ambient temperature, has elapsed; when the position of a shift lever has been changed; when the height of the vehicle has changed by an amount greater than a predetermined amount; or when the driver releases a brake pedal which has been continuously operated after completion of the parking brake activation control.

1. Field of the Invention
The present invention relates to an electric parking brake apparatus capable of operating a parking brake of a vehicle by use of electric drive means such as an electric motor.
2. Description of Related Art
Japanese Patent Application Laid-Open (kokai) No. 2002-225701 discloses a conventional electric parking brake apparatus of such a type. The disclosed apparatus includes a parking brake, which consists of a brake disk and a brake pad for generating a braking force corresponding to a pressure-contact force at the time of pressure contact with the brake disk; and an electric motor for driving the brake pad. Parking brake activation control is performed in such a manner that the motor is operated until current flowing through the motor and increasing with the pressure contact force reaches a predetermined target value, so as to bring the parking brake into an activated state in which the parking brake can stop the vehicle and maintain it in the stopped state, and subsequently, the operation of the motor is stopped.
Further, in the disclosed apparatus, between the motor and the parking brake is disposed a speed reduction mechanism including a plurality of gears and adapted to permit transmission of drive torque of the motor to the brake pad, while preventing transmission to the motor of a force stemming from the pressure contact force of the brake pad. Therefore, even after the operation of the motor is stopped after completion of the parking brake activation control (even after the current flowing through the motor decreases to zero), the pressure contact force can be held, whereby the vehicle can be stopped and maintained in the stopped state.
Incidentally, a parking brake as described above is typically disposed in the vicinity of a service brake of a vehicle, and therefore, heat generated at the service brake is transferred to the parking brake. Accordingly, when the temperature of the service brake becomes high as a result of repeated use of the service brake during traveling of the vehicle, the temperatures of components (brake disk, brake pads, etc.) of the parking brake also become high, with resultant thermal expansions of the components. Therefore, when the parking brake is brought into an activated state in such a condition by means of the above-described parking brake activation control and the braking force of the parking brake is held by the above-described action of the speed reduction mechanism, depending on the relation between thermal expansion coefficients of the components of the parking brake, the braking force of the parking brake may decrease as the temperatures of the components decrease with time, because of differences in thermal contraction/expansion among the components.
In order to solve such a drawback, the disclosed apparatus is configured in such a manner that even after the parking brake enters an activated state upon completion of the above-described parking brake activation control, the parking brake activation control is repeated every time a predetermined time elapses, to thereby maintain the braking force of the parking brake at a proper level.
However, the disclosed apparatus has the following problem. The temperature decrease speed of each component of the parking brake depends on the temperature difference between the temperature of the component and the ambient temperature, and increases with the temperature difference. Therefore, when the temperatures of the components of the parking brake are extremely high at the time of completion of the parking brake activation control, the temperature decrease speeds of the components after that time become high, so that the braking force of the parking brake decreases considerably before the above-described predetermined time elapses after that time. As a result, the disclosed apparatus may fail to maintain the braking force of the parking brake at a desired level through the elapse of the predetermined time.
Moreover, in the case where the braking force of the parking brake drops because of a factor other than the temperature decreases of the components of the parking brake at a certain point in time after completion of the above-described parking brake activation control, as in the above-described case, the disclosed apparatus may fail to maintain the braking force of the parking brake at a desired level through the elapse of the predetermined time.
Meanwhile, it has been known that even when the pressure contact force of the brake pad against the brake disk is constant, the braking force of the parking brake decreases when the temperatures of the components of the parking brake increase, because of a drop in friction coefficient of the friction surface of the brake pad. However, in the disclosed apparatus, a target value of current flowing through the motor (a target value of pressure contact force) used in the above-described parking brake activation control is a constant value irrespective of the temperatures of the components of the parking brake. Therefore, in the case where the temperatures of the components of the parking brake at the time of completion of the parking brake activation control are extremely high, the parking brake may fail to generate a necessary braking force even at that time. As described above, the disclosed apparatus has a problem in that after the parking brake enters an activated state upon completion of the parking brake activation control, the parking brake may fail to properly maintain a necessary braking force, depending on various stop states of the vehicle.


A thermal recirculation valve (TRV) is described that provides for effective fuel module heating during cold operation to mitigate fuel waxing or gelling issues. The TRV allows for the control of heated return fuel flow into the module dependent upon the module's outlet fuel temperature without the return fuel directly contacting the wax element. The wax element is isolated from direct contact with the higher temperature return fuel through use of an elastomeric seal which prevents return fuel from directly contacting the wax element. In addition, the wax element is positioned in the fuel outlet of the module.

TRVs are existing components in the market today, but are not optimized for best performance due to common packaging schemes for fuel filtration applications. FIG. 1 illustrates a known TRV. The TRV includes fuel filtration module 1, a fuel filtration module inlet 2, a fuel filtration module outlet 3, a TRV inlet 4, a TRV passage to module 5, a return fuel flow control valve 6, a TRV outlet 7, a thermal wax element 8, and filtration media 9. Fuel entering the inlet 2 is forced to flow through the media 9 before flowing to the outlet 3. Any return fuel that returns through the passage 5 contacts the wax element 8 and then flows through the media 9 to the outlet 3.
In most known applications, the TRV wax elements are positioned such that there is either radiant or conduction heat transfer from the return fuel due to the flow passage design near the sensing region which causes the return fuel to directly contact the wax element. This causes poor performance due to rapid heat transfer to the sensing region location of the wax element, which could cause the valve to prematurely close during cold operating conditions.

Thermal recirculation valve for fuel filtration module


To provide a spool wrapped length of conductor cable with an exposed cable end at the outer perimeter of a spool flange for the starting wrap of the cable, a cable end guide is secured to the inside face of a spool flange by means of staples or adhesives. The cable end guide provides a supplemental interior flange face having a cable supporting outer edge along a spiral path around the spool hub into substantially tangent alignment with the spool hub. The cable guide may be vacuum formed from thermoplastic sheet into two or more sectors, each sector being physically independent of the others and nestably stackable with corresponding sectors.

The present invention generally relates to spool structures such as are used to wind and transport great lengths of communication and power transmission cable.
Cable is a term used in many industries to describe a rope-like structure that is relatively flexible, has a substantially constant cross sectional shape and an indefinite length. Communications cable may be a fiber optic wave guide within a protective sheath or one or more insulated electrical conductors. Such communication cable is generally produced as a continuous process having a substantially uniform surface texture and circular cross-sectional shape. Since the production is continuous, the length of such cable is determined most often by the length of a manageable quantity, whether in terms of weight or volumetric bulk. Commercial power transmission cable and bundled trunk lines of communication cable are generally wound on large spools of several thousand pounds or more and suitable for handling only by heavy duty power equipment.
The basic construction of an electric conductor or optical wave guide cable spool comprises a substantially cylindrical hub having a surface perimeter that is generally equidistant radially from an elongated hub axis. A convenient axial length of the hub is terminated at opposite axial ends by respective radial flanges. These flanges are generally circular about a center at the hub cylinder axis. The inside or oppositely facing surfaces of these spool flanges generally lie in a plane that is normal to the hub cylinder axis.
One of the characteristics distinctive to the power and communications industries is the need to verify, often frequently, the continuity of cable wrapped upon a transport spool. Hence, physical access to that end of the cable starting the spool wrap is essential. Traditionally, access to the starting end of the cable is assured by securing the starting end to the outer perimeter of one spool flange. From the flange outer edge, the cable lies contiguously with the inner face of the flange along a tangent course with the reel hub perimeter. From tangency with the reel hub, rotational wrapping about the hub begins and progresses along the axial length of the hub to the opposite end flange. Here, the winding cable length begins to overlie those wraps below and proceeds with a second layer of side-by-side wraps progressing along the axial length of the hub back toward the first flange.
This progression continues, layer upon layer, until the desired cable length is wound upon the spool frame. Due to the presence of the cable starting end lying against the inside face of the first flange, a discontinuity is presented along the axial space between the opposite flange faces. This discontinuity allows for one less wrap about the spool hub perimeter along a line between the starting end of the cable and the opposite flange face as compared to the remainder of the hub length between opposite flanges.
One consequence of this hub length discontinuity presented by physical access to the cable starting end is a sliding and often abrasive contact between cable surfaces during the unreeling process as an unwinding wrap slides against the starting end of the cable. Additionally, this discontinuity in the distance between opposing flange faces disrupts the uniform tension and order in the lay of the wrap about the spool hub.
One prior art approach to this wrap discontinuity issue has been to provide a channel in the inside face of one flange to receive the starting cable end. This solution, however, significantly increases the spool construction cost. Another prior art solution has been to secure a layer of inexpensive material against the inside face of the first flange to provide a false inside face for the first flange that includes a protective channel for receipt of the cable starting end. The material substance of such a false face may be soft and inexpensive such as foamed plastic sheet.
A major difficulty with plastic foam sheet for this purpose has been the inability to store the article prior to use in a nested condition. Additionally, such materials generally are somewhat fragile and easily broken.
It is, therefore, an object of the present invention to provide a spiral course reel guide that may be transported and stored in a densely packed, nested condition.
Another object of the invention is provision of a spiral reel guide that is vacuum formed from a single sheet of tough and resilient thermoformed plastic.


The Vehicle Appearance Protection and Enhancement Apparatuses, Methods and Systems (“APEPS”) transforms initial product attribute data inputs via APEPS components into future product value enhancement verification outputs. In various aspects of the various embodiments of the APEPS system, an Automotive Appearance Protection Trade Credit, voucher, coupon, allowance, guarantee, etc. is provided to a user. The trade credit may equal a percentage, flat dollar amount, or dollar for dollar up to a maximum amount of the original automotive appearance protection/product purchase/lease price. The customer is provided with tangible value upon leaving a dealership, which states that by applying these products/protections the vehicle trade-in value will be enhanced. The APEPS provides a web portal for both customers and dealers that will automatically calculate and continuously update the trade credit.

Insurance companies offer policies to drivers. Such policies allow drivers to receive payment after accidents occur to finance repairs to their damaged automobiles.
Generally, the leading number(s) of each citation number within the drawings indicates the figure in which that citation number is introduced and/or detailed. As such, a detailed discussion of citation number 101 would be found and/or introduced in FIG. 1. Citation number 1001 is introduced in FIG. 10, etc. Any citation and/or reference numbers are not necessarily sequences but rather just example orders that may be rearranged and other orders are contemplated.

Vehicle appearance protection and enhancement apparatuses, methods and systems


A disk device includes: an optical pick-up, operable to reproduce data recorded in a disk; a flaw detector, operable to output a flaw detecting signal when a flaw formed on the disk is detected; and a jump controller, operable to control a track jump of the optical pick-up including a first track jump and a second track jump subsequent to the first track jump. A timing of starting to control the track jump corresponding to a still reproduction mode is determined based on a rotational position of the disk. When the flaw detecting signal is outputted in a time period in which the jump controller controls the first track jump corresponding to the still reproduction mode, the jump controller sets a timing for stating the second track jump to a timing different from a timing for starting the first track jump.

The present invention relates to a disk device including a flaw detecting unit for outputting a flaw detecting signal when a flaw formed in a disk is detected, and more particularly to a disk device in which when it is detected that the flaw detecting signal is outputted at the time of controlling a track jump corresponding to a still reproduction, a timing for starting a subsequent track jump is controlled properly.
In a still reproduction mode of video and audio information recorded in a DVD, a track jump toward an inner peripheral side is carried out by one track for each rotation of the DVD to repeatedly reproduce the same position. Further, in the track jump, after a pulse is applied for accelerating and moving a reading position toward the inner peripheral side, a pulse is applied for reducing the moving speed of the reading position and stopping the reading position. Then, when the track jump is completed, a servo control of a tracking is resumed (This technique is referred to as a first related art).
Further, when a DPD (Differential Phase Detection) signal is used as a tracking error signal, if the landing position of the track jump corresponds to a part (a linking part) in which data is written and connected or a part in which since the data is not recorded, a reproducing RF signal is not obtained, the tracking error signal is undesirably disturbed after the track jump lands so that a reproducing operation cannot be preferably carried out from a desired sector. Thus, a below-described technique is proposed.
Namely, in this technique (This technique is referred to as a second related art), when the track jump is started, it is decided whether or not a landing position obtained when the track jump is carried out from the current reading position is a position suitable for landing. That is, whether the landing position is the linking part or the part in which the data is not recorded is examined. Then, when the landing position is the linking part or the part in which the data is not recorded, a timing of starting the track jump is shifted so that the landing position does not correspond to the linking part or the part in which the data is not recorded. Further, in the technique, the part in which the data is not recorded is a sector that is replaced due to a flaw (for instance, see JP-A-2001-34961).
Further, a below-described technique is proposed (This technique is referred to as a third related art). In this technique, when a track jump is carried out, the applying time of a pulse for carrying out the track jump is determined not on the basis of a tracking error signal, but on the basis of a control signal outputted from a deciding circuit. The deciding circuit decides whether a jump is too sufficient or insufficient from the tracking error signal when the pulse is applied for a prescribed time in the track jump of a previous time to generate the control signal showing a proper applying time in accordance with the decided result. Then, when a subsequent track jump is carried out, the applying time of the pulse for the track jump is determined not on the basis of the tracking error signal, but on the basis of the control signal outputted from the deciding circuit. As a result, even when noise is generated in the tracking error signal owing to the flaw of an optical disk, the track jump is carried out without a difficulty (for instance, see JP-A-5-342783).
However, when the first related art is employed, below-described problems arise. That is, when the flaw is present in the landing position, a normal tracking error signal is not obtained. Therefore, a tracking may not be normally resumed after the track jump. Namely, a situation arises that the track jump of an optical pick-up cannot successfully arrive at an adjacent track so that the reading position of the optical pick-up greatly shifts in the radial direction. Then, when the reading position of the optical pick-up greatly shifts in the radial direction, the level of a tracking error signal may oscillate with a large amplitude so that a driving signal oscillating with a large amplitude is applied to a tracking actuator. As a result, an objective lens greatly oscillates in the radial direction. Thus, an abnormal sound such as creak is generated from a disk drive to give a discomfort to a user.
When the second related art is employed, if a replacement process is carried out so that an area having the flaw is not used, the track jump of the optical pick-up can be avoided from landing at a position where the flaw is present. However, even when there is such a flaw as to disturb the tracking error signal at the time of landing, since all the part having the flaw is not necessarily replaced, a situation may possibly arise that the track jump of the optical pick-up lands at the position having the flaw. Further, in the case of the disk exclusive for a reproduction, since the replacement process is not carried out, the technique cannot be applied. Further, since a process for detecting whether or not the landing position is an area that is subjected to the replacement process includes a complication calculation, the structure of software is undesirably complicated.
Since the third related art is the technique for performing the track jump without referring to the tracking error signal, the third related art is hardly applied to solve the problems in the first related art.