Self-discharge is a phenomenon in
batteries. Self-discharge decreases the
shelf life
Shelf life is the length of time that a commodity may be stored without becoming unfit for use, consumption, or sale. In other words, it might refer to whether a commodity should no longer be on a pantry shelf (unfit for use), or no longer on a s ...
of batteries and causes them to have less than a full charge when actually put to use.
How fast self-discharge in a battery occurs is dependent on the type of battery, state of charge, charging current, ambient temperature and other factors.
Primary batteries are not designed for recharging between manufacturing and use, and thus to be practical they must have much lower self-discharge rates than older types of secondary cells. Later, secondary cells with similar very low self-discharge rates were developed, like
low-self-discharge nickel–metal hydride cells.
Self-discharge is a chemical reaction, just as closed-circuit discharge is, and tends to occur more quickly at higher temperatures. Storing batteries at lower temperatures thus reduces the rate of self-discharge and preserves the initial energy stored in the battery. Self-discharge is also thought to be reduced as a
passivation layer develops on the electrodes over time.
Typical self-discharge by battery type
References
Further reading
* Wu and White,
Self-Discharge Model of a Nickel-Hydrogen Cell" Journal of the Electrochemical Society, 147 (3) 901-909 (2000)
External links
Battery dischargersDescription and treatment of sulphated batteries
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Electric battery
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Rechargeable batteries