Convert Screwdriver To 18 Volt Lithium
I will not say anything new in this article, but I just want to share the experience of upgrading the batteries of my old Makita screwdriver. Initially, this tool was designed for nickel-cadmium batteries (which had already died long ago, as they had died, and those bought in replacement were the same). The disadvantages of Ni-Cd are known: low capacity, short life, high price. Therefore, manufacturers of cordless tools have long switched to lithium-ion batteries.
Well, what about those who have an old instrument? Yes, everything is very simple: throw out Ni-Cd cans and replace them with Li-Ion in the popular 18650 format (marking indicates a diameter of 18 mm and a length of 65 mm).
What kind of board do you need and what elements are needed to convert a lithium-ion screwdriver
So, here is my 9.6 V battery with a capacity of 1.3 Ah. At maximum charge, it has a voltage of 10.8 volts. Lithium-ion cells have a nominal voltage of 3.6 volts, maximum. 4.2. Therefore, to replace the old nickel-cadmium cells with lithium-ion cells, I need 3 cells, their operating voltage will be 10.8 volts, the maximum. 12.6 volts. Exceeding the rated voltage will not harm the motor in any way, it will not burn out and with a larger difference, there is no need to worry.
Lithium-ion cells, as everyone has long known, strongly dislike recharging (voltage above 4.2 V) and excessive discharge (below 2.5 V). With such excesses of the operating range, the element degrades very quickly. Therefore, lithium-ion cells always work in tandem with the electronic board (BMS. Battery Management System), which controls the cell and controls both the upper and lower voltage limits. This is a protection board that simply disconnects the jar from the electrical circuit when the voltage goes beyond the operating range. Therefore, in addition to the elements themselves, such a BMS board will be required.
Now there are two important points with which I experimented several times unsuccessfully, until I came to the right choice. This is the maximum allowable working current of the Li-Ion elements themselves and the maximum working current of the BMS board.
In a screwdriver, operating currents at high load reach 10-20 A. Therefore, you need to buy elements that are capable of delivering high currents. Personally, I successfully use 30-ampere 18650 cells manufactured by Sony VTC4 (with a capacity of 2100 mAh) and 20-ampere Sanyo UR18650NSX (with a capacity of 2600 mAh). They work fine in my screwdrivers. But, for example, Chinese TrustFire 2500 mAh and Japanese light green Panasonic NCR18650B at 3400 mAh are not suitable, they are not designed for such currents. Therefore, do not chase the capacity of the elements. even 2100 mAh is more than enough; the main thing when choosing is not to miscalculate with the maximum permissible discharge current.
And in exactly the same way, the BMS board must be rated for high operating currents. I saw on Youtube how people collect batteries on 5 or 10-amp boards. I don’t know, personally, when I turned on the screwdriver, such boards immediately went to defense. In my opinion, this is a waste of money. I will say that Makita itself puts 30-ampere boards in its batteries. Therefore, I use 25-amp BMS purchased on Aliexpress. They cost about 6-7 dollars and are searched for by request "BMS 25A". Since you need a board for an assembly of 3 elements, you need to look for a board in the name of which will be "3S".
Another important point: some boards may have different contacts for charging (designation “C”) and load (designation “P”). For example, a board can have three pins: “P-”, “P”, and “C-”, as on a native Makita lithium-ion board. Such a board will not suit us. Charging and discharging (charge / discharge) must be done through one contact! That is, the board should have 2 working contacts: just “plus” and just “minus”. Because our old charger also has only two pins.
In general, as you might have guessed, with my experiments I threw a ton of money both on the wrong elements and on the wrong boards, having made all the mistakes that could have been made. But got invaluable experience.
How to disassemble a screwdriver battery
How to disassemble the old battery? There are batteries where the halves of the case are screwed, but there is also glue. My batteries are just the last, and I generally thought for a long time that they could not be taken apart. It turned out that it’s possible if you have a hammer.
In general, with the help of intensive blows to the perimeter of the edge of the lower part of the body (a hammer with a nylon head, the battery must be kept in hand in weight), the gluing place is successfully disconnected. The case is not damaged in any way, I have already disassembled 4 pieces.
Видео: Convert Screwdriver To 18 Volt Lithium
Part of interest to us.
From the old circuit, only contact plates are needed. They are firmly welded to the upper two elements by spot welding. You can pick out the welding with a screwdriver or pliers, but you need to pick it as carefully as possible so as not to break the plastic.
Everything is almost ready for further work. By the way, I left the standard temperature sensor and circuit breaker, although they are no longer particularly relevant.
But it is very likely that the presence of these elements is necessary for the normal operation of a standard charger. Therefore, I strongly recommend that you save them.
Putting a lithium-ion battery
Here are the new elements of the Sanyo UR18650NSX (you can find them on this article on Aliexpress) with a capacity of 2600 mAh. For comparison, the old battery had a capacity of only 1300 mAh, half as much.
It is necessary to solder the wires to the elements. Wires must be taken with a cross-section of at least 0.75 sq. Mm, because the currents we have will be considerable. A wire with such a cross section normally works with currents of more than 20 A at a voltage of 12 V. It is possible to solder lithium-ion banks, short-term overheating will not harm them in any way, this has been checked. But you need a good high-speed flux. I use TAGS glycerin flux. Half a second. and you’re done.
Solder the other ends of the wires to the board according to the diagram.
On the battery connectors, I always run even thicker wires of 1.5 sq. Mm. because the place allows. Before soldering them to the mating contacts, I put on a piece of heat-shrink tubing on the board. It is necessary for additional isolation of the board from the battery cells. Otherwise, the sharp edges of the solder can easily rub or pierce a thin film of the lithium-ion cell and cause a short circuit. You can not apply heat shrinkage, but at least something insulating to lay between the board and the elements is absolutely necessary.
Now everything is insulated as it should.
The contact part can be fixed in the battery case with a couple of droplets of super-glue.
The battery is ready for assembly.
It’s good when the case is screwed, but this is not my case, so I just glue the halves together with the “Moment” again.
The battery is charged with a standard charger. True, the algorithm of work is changing.
I have two chargers: DC9710 and DC1414 T. And they now work differently, so I’ll tell you exactly how.
Makita DC9710 Battery Charger and Li-ion Battery
Previously, the battery charge was controlled by the device itself. Upon reaching the full level, it stopped the process and signaled the completion of charging with a green indicator. But now level control and power off are handled by the BMS circuit we have installed. Therefore, when charging is complete, the red LED on the charger will simply turn off.
If you have just such an old device. you’re in luck. Because everything is simple with him. LED Lights. there is a charge. Off. charging is complete, the battery is fully charged.
Makita DC1414 T Battery Charger and Li-ion Battery
There is a small nuance that you need to know. This memory is newer and it is designed to charge a wider range of batteries from 7.2 to 14.4 V. The charging process on it goes as usual, the red LED is on:
But when the battery (which is supposed to have a maximum voltage of 10.8 V in the case of NiMH cells) reaches 12 volts (we have Li-Ion cells with a maximum total voltage of 12.6 V), the roof will be blown down by the charger. Because he will not understand what kind of battery he is charging: either 9.6-volt, or 14.4-volt. And at that moment, the Makita DC1414 will enter error mode, alternately blinking red and green LEDs.
This is normal! Your new battery will still charge. though not completely. The voltage will be approximately 12 volts.
That is, you miss some part of the capacity with this charger, but it seems to me that you can survive it.
Total modernization of the Bosch battery cost about 1,000 rubles. The new Makita Makita PA09 costs twice as much. over, in the end, we got twice the capacity, and further repairs (in the event of a failure several times) will consist only in the replacement of lithium-ion cells.
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"Kufanya ""screwdriver"" ya 18V ya lithiamu: ""Nitafanya kazi kwa kutumia screwdriver ya zamani ya Makita." Kwa mfano, kwa mfano, betri ya nikeli-cadmium, ambayo ilikuwa imepatikana kwa muda mrefu, ilibadilishwa na kuuzwa kwa bei ya chini. Hasara za Ni-Cd zinajulikana: uwezo mdogo, maisha mafupi, bei ya juu. Kwa hiyo, watengenezaji wa vifaa visivyo na waya wamebadilisha muda mrefu kwa betri za lithiamu-ion. Namna gani wale walio na ala ya muziki ya zamani? Ni rahisi sana: kutupa nje NiCd na kuchukua nafasi yao na Li-Ion katika maarufu 18650 format (kuashiria inaonyesha kipenyo cha 18mm na urefu wa 65mm). Kwa hivyo, ni nini cha kuunda na kuunda betri ya lithiamu-ion, na ni nini cha kuunda betri ya lithiamu-ion, na ni nini cha kuunda betri ya lithiamu-ion, na ni nini cha kuunda betri ya lithiamu-ion, na ni nini cha kuunda betri ya lithiamu-ion. Wakati wa malipo ya juu, ina voltage ya 10.8 volts. Lithium-ion cells ni za voltage ya volts 3.6 na zina uwezo wa kuendesha umeme wa volts 3.6. 4.2.2. (a) Ni nini kinachohusika? Kwa hiyo, ili kubadilisha seli za zamani za nikeli-cadmium na seli za lithiamu-ion, ninahitaji seli tatu, voltage yao ya uendeshaji itakuwa 10.8 volts, kiwango cha juu. 12.6 volts Zaidi ya voltage ya kiwango cha juu haitaumiza motor kwa njia yoyote, haitachoma na tofauti kubwa haipaswi kuwa na wasiwasi. Lithium-ion seli, kama kila mtu amekuwa muda mrefu alijua, vikali kupenda recharge (voltage juu ya 4.2V) na discharge kupita kiasi (chini ya 2.5V). Kwa ziada kama hizo za mbalimbali ya uendeshaji, kipengele huharibika haraka sana. Kwa hiyo, lithiamu-ion seli daima kazi katika tandem na bodi ya elektroniki (BMS). Battery Management System), ambayo inadhibiti kiini na kudhibiti wote juu na chini ya voltage mipaka. Hii ni bodi ya ulinzi ambayo tu disconnects jar kutoka mzunguko wa umeme wakati voltage huenda zaidi ya mbalimbali ya uendeshaji. Kwa hiyo, pamoja na vipengele wenyewe, kama BMS bodi itakuwa zinahitajika. Sasa kuna mambo mawili muhimu ambayo nilijaribu mara kadhaa bila mafanikio, mpaka nilipopata chaguo sahihi. Hii ni kiwango cha juu cha kuruhusiwa kazi sasa ya Li-Ion vipengele wenyewe na kiwango cha juu cha kazi sasa ya BMS bodi. Katika screwdriver, kazi mikondo katika mzigo mkubwa kufikia 10-20 A. Kwa hiyo, unahitaji kununua vipengele ambavyo vinaweza kutoa mikondo mikubwa. Kwa mfano, kwa mfano, unaweza kutumia vifaa vya 30 ampere (VTC4) na 20 ampere (SANYU UR18650NX) na vifaa vya 30 ampere (VTC4) na 20 ampere (SANYU UR18650NX). Wao kazi vizuri katika screwdrivers yangu. Kwa mfano, Panasonic NCR18650B na Trustfire 2500mAh, ambayo ni sawa na Panasonic NCR18650B, ambayo ni sawa na Panasonic NCR18650B, ambayo ni sawa na Panasonic NCR18650B, ambayo ni sawa na Panasonic NCR18650B. Kwa hiyo, usifuatilie uwezo wa vitu. Hata 2100 mAh ni zaidi ya kutosha; jambo kuu wakati wa kuchagua ni si miscalculate na kiwango cha juu kuruhusiwa discharge sasa. Kwa mfano, BMS lazima iwe na kiwango cha juu cha umeme. Kwa mfano, unaweza kuona video ya YouTube ya watu wakikusanya betri kwenye bodi za 5 au 10 amps. Sijui, binafsi, wakati mimi akageuka juu ya screwdriver, bodi kama mara moja akaenda kwa ulinzi. Kwa maoni yangu, hii ni kupoteza pesa. Makita inaongeza 30 amps kwenye betri zake Kwa hivyo, mimi hutumia BMS ya 25-amps kununuliwa kwenye Aliexpress. "Kama vile, inagharimu karibu $ 6 kwa kila mtu, na inapatikana kwa ""BMS 25A.""" "Kama unachohitaji bodi kwa ajili ya mkutano wa vipengele 3, unahitaji kuangalia kwa bodi ambayo jina lake itakuwa ""S.""" Jambo jingine muhimu: baadhi ya bodi inaweza kuwa na mawasiliano tofauti kwa ajili ya malipo (maelezo <unk>C<unk>) na mzigo (maelezo <unk>P<unk>). Kwa mfano, bodi inaweza kuwa na pini tatu: <unk>P-<unk>, <unk>P<unk>, na <unk>C-<unk>, kama kwenye bodi ya asili ya Makita lithiamu-ion. Bodi kama hiyo haitatufaa. Kuchaji na kutolewa (chaji kutolewa) lazima kufanyika kupitia mawasiliano moja! Hiyo ni, bodi inapaswa kuwa na mawasiliano ya kazi ya 2: tu <unk>plus<unk> na tu <unk>minus<unk>. Kwa sababu chaja yetu ya zamani pia ina vijiti viwili tu. Kwa ujumla, kama unaweza kuwa guessed, na majaribio yangu mimi kutupa tani ya fedha wote juu ya vipengele makosa na juu ya bodi makosa, baada ya kufanya makosa yote ambayo inaweza kuwa alifanya. Lakini alipata uzoefu wenye thamani. Jinsi ya kuondoa betri ya screwdriver Jinsi ya kuondoa betri ya zamani? Kuna betri ambapo nusu ya kesi ni screwed, lakini pia kuna gundi. Batri zangu ni za mwisho tu, na kwa ujumla nilifikiri kwa muda mrefu kwamba hazingeweza kutenganishwa. Ilionekana kwamba inawezekana ikiwa una nyundo. Kwa ujumla, kwa msaada wa pigo kali kwa perimeter ya makali ya sehemu ya chini ya mwili (shuti na nylon kichwa, betri lazima kushikiliwa katika mkono kwa uzito), glueing mahali ni mafanikio kukatika. Kwa sababu hii, hakuna kitu kilichoharibiwa, na tayari nimepanga kuondoa vipande vinne. "Kama vile ""screwdriver"" ya 18 volts, ""lithium"" ya 18 volts, ""lithium"" ya 18 volts, ""lithium"" ya 18 volts, ""lithium"" ya 18 volts, ""lithium"" ya 18 volts." Kutoka mzunguko wa zamani, tu sahani ya mawasiliano zinahitajika. Wao ni imara welded kwa vipengele viwili vya juu kwa welding sehemu. Unaweza kuondoa welding kwa screwdriver au pliers, lakini unahitaji kuichukua kwa uangalifu iwezekanavyo ili usivunje plastiki. Karibu kila kitu kiko tayari kwa ajili ya kazi zaidi. Kwa njia, mimi kushoto kiwango cha joto sensor na circuit breaker, ingawa wao si tena hasa muhimu. Lakini ni uwezekano mkubwa sana kwamba uwepo wa vipengele hivi ni muhimu kwa ajili ya kazi ya kawaida ya chaja ya kawaida. Kwa hiyo, ninakupendekeza sana uhifadhi. Lithium-ion betri ya Sanyo UR18650NX ina uwezo wa kuendesha umeme wa mAh 2600. Kwa kulinganisha, betri ya zamani ilikuwa na uwezo wa 1300 mAh tu, nusu ya kiasi hicho. Ni muhimu kwa solder waya kwa vipengele. Wire lazima kuchukuliwa na sehemu ya msalaba ya angalau 0.75 sq. Mm, kwa sababu mikondo tutakayo itakuwa kubwa. Wire na sehemu ya msalaba kama hiyo kawaida hufanya kazi na mikondo ya zaidi ya 20A kwa voltage ya 12V. Inawezekana kuunganisha benki za lithiamu-ion, joto la muda mfupi halitawaumiza kwa njia yoyote. Lakini unahitaji mtiririko mzuri wa kasi ya juu. TAGS Glycerin Flux Nusu ya sekunde. na umemaliza. Solder mwisho mwingine wa waya kwa bodi kulingana na mchoro. Kwa upande wa kitanzi cha betri, unaweza kutumia waya za 1.5 sq. Mm. (Kicheko) kwa sababu mahali hapo panaruhusu. Kabla ya kuunganisha viungo vya kuunganisha, niliweka kipande cha bomba la kupunguza joto kwenye ubao. Ni muhimu kwa ajili ya kutengwa ziada ya bodi kutoka seli betri. Vinginevyo, kingo kali za solder zinaweza kwa urahisi kupasua au kupenya filamu nyembamba ya seli ya lithiamu-ion na kusababisha mzunguko mfupi. Unaweza kutumia joto shrinkage, lakini angalau kitu insulating kuweka kati ya bodi na vipengele ni lazima kabisa. Sasa kila kitu kimefichwa kama inavyopaswa kuwa. Sehemu ya mawasiliano inaweza kuwa fasta katika kesi ya betri na droplets chache ya super-glue. Betri ni tayari kwa ajili ya mkusanyiko. Ni <unk> nzuri wakati kesi ni screwed, lakini hii si kesi yangu, hivyo mimi tu glue nusu pamoja na <unk>Moment<unk> tena. Betri ni kushtakiwa na charger kawaida. Ni kweli, algorithm ya kazi inabadilika. DC910 na DC1414T ni chaja mbili za umeme ambazo zina uwezo wa kuchaji umeme kwa njia tofauti. Makita DC910 Battery Charger na Li-Ion Battery - Kwa mfano, ina uwezo wa kuchaji betri ya betri ya gari. Baada ya kufikia kiwango kamili, ilisimamisha mchakato na kuashiria kukamilika kwa malipo na kiashiria cha kijani. Lakini sasa udhibiti wa kiwango na nguvu off ni kushughulikiwa na mzunguko BMS tumeweka. Kwa hiyo, wakati kuchaji ni kamili, nyekundu LED juu ya chaja itakuwa tu kuzima. Kama una tu kama kifaa cha zamani. wewe ni katika bahati. Kwa sababu kila kitu ni rahisi kwake. Taa za LED. kuna malipo. Ondoka. Kuchaji kumekamilika, betri imeshtakiwa kikamilifu. Makita DC1414 T Battery Charger na Li-Ion Battery - Ni nini? Kwa mfano, kwa betri ya Li-Ion, ina voltage ya juu ya 12.6V, na wakati betri ya Li-Ion inapofikia voltage ya juu ya 12.6V, ina voltage ya juu ya 12.6V. Kwa mfano, unaweza kuamua aina ya betri ya kuchaji, ikiwa ni 9.6V au 14.4V. Wakati huo huo, Makita DC1414 itaingia katika hali ya makosa, ikitoa taa nyekundu na kijani. Hilo ni jambo la kawaida! Betri yako mpya bado itashikilia. ingawa si kabisa. Voltage ya umeme ni karibu 12 volts. Kwa hivyo, kwa sababu ya uwezo wa kuchaji, unaweza kuepuka kuchaji kwa njia hii, lakini kwa kweli, unaweza kuifanya. Kwa mfano, kwa ajili ya upanuzi wa betri ya Bosch, gharama ya jumla ni karibu ruble 1,000. Makita PA09 inaonekana kuwa ya bei rahisi zaidi "Kama matokeo, tumepata uwezo mara mbili, na ukarabati zaidi (katika tukio la kushindwa mara kadhaa) itakuwa tu katika kubadilisha seli za lithiamu-ion. """ Kumbuka: makala hii na picha zilizo ndani yake ni chini ya haki za uchapaji. Uzalishaji wa sehemu au kamili kwenye rasilimali nyingine bila idhini ni marufuku.