etc.), they are formulated to last longest in periodical use items. This type of battery is better suited for use in low-drain devices such as remote controls or for devices that are used periodically such as flashlights (torches), television remote control handsets, portable radios, etc. If they are discharged by less than 25%, they can be recharged for hundreds of cycles to about 1.42 V. If they are discharged by less than 50%, they can be almost fully recharged for a few dozen cycles, to about 1.32 V. After a deep discharge, they can be brought to their original high-capacity charge only after a few charge-discharge cycles. Recharging of disposable alkalines Manufacturers do not support recharging of disposable alkaline batteries, and warn that it may be dangerous. Despite this advice, alkaline batteries have been recharged, and chargers have been available. The capacity of a recharged alkaline battery declines with number of recharges, until it becomes unusable after typically about ten cycles. Low-ripple direct current is not suitable for charging disposable alkaline batteries; more suitable is a current pulsed at a rate of 40 to 200 pulses per second, with an 80% duty cycle. Pulsed charging appears to reduce the risk of electrolyte—usually potassium hydroxide (KOH)—leakage. The charging current must be low to prevent rapid production of gases that can rupture the cell. Cells that have leaked electrolyte are unsafe and unsuitable for reuse. Fully discharged cells recharge less successfully than only partly depleted cells, particularly if they have been stored in a discharged state—battery charger manufacturers do not claim to recharge dead cells. Attempting to recharge a discharged alkaline battery can cause the production of gas within the sealed canister; pressure generated by rapid accumulation of gas can open the pressure-relief seal and cause leakage of electrolyte. Potassium hydroxide in the electrolyte is corrosive and may cause injury and damage, particularly corroding the battery contacts in the equipment. As an alkaline battery is discharged, chemicals inside the battery react to create an electric current. As the chemicals are used up and the products of the reaction accumulate, eventually the battery is no longer able to deliver adequate current, and the battery is depleted. By driving a current through the battery in the reverse direction, the equilibrium can be shifted back towards the original reactants. Different batteries rely on different chemical reactions. Some reactions are readily reversible, some are not. The