How to Restore and Prolong Nickel-based Batteries?The effects of crystalline formation

are most pronounced if a nickel-based battery is

left in the charger for days, or if repeatedly recharged without a periodic full

discharge. Since most applications do not use up all energy before recharge, a periodic

discharge to 1V/cell (known as exercise) is essential to prevent the buildup of

crystalline formation on the cell plates. This maintenance is most critical for the NiCd

battery.
All NiCd batteries in regular use and on

standby mode (sitting in a charger for operational readiness) should be exercised once per

month. Between these monthly exercise cycles, no further service is needed. The battery

can be used with any desired user pattern without the concern of memory.
The NiMH battery is affected by memory

also, but to a lesser degree. No scientific research is available that compares NiMH with

NiCd in terms of memory degradation. Neither is information on hand that suggests the

optimal amount of maintenance required to obtain maximum battery life. Applying a full

discharge once every three months appears right. Because of the NiMH battery’s shorter cycle life, over-exercising is

not recommended.
A hand towel must be cleaned periodically. However, if it were washed after each

use, its fabric would wear out very quickly. In the same way, it is neither necessary nor

advisable to discharge a rechargeable battery before each charge �" excessive cycling puts

extra strain on the battery.
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