Battery Cycle Life: The number of cycles, to a specified depth of discharge, that a cell or battery can undergo before failing to meet its specified capacity or efficiency performance criteria.

Battery Life Cycle

Battery cycle life is the number of charge/discharge cycles possible before the cells fail to operate satisfactorily. (The term shelf life is used to describe how long a battery will retain its performance between manufacture and use.)

Available capacity of all batteries drops with decreasing temperature. In contrast to most of today’s batteries, the Zamboni pile, invented in 1812, offers a very long service life without refurbishment or recharge, although it supplies current only in the nanoamp range. The Oxford Electric Bell has been ringing almost continuously since 1840 on its original pair of batteries, thought to be Zamboni piles.

Self-discharge

Disposable batteries typically lose 8 to 20 percent of their original charge per year when stored at room temperature (20–30 °C).[40] This is known as the “self-discharge” rate, and is due to non-current-producing “side” chemical reactions that occur within the cell even when no load is applied. The rate of side reactions is reduced for batteries are stored at lower temperatures, although some can be damaged by freezing.

Old rechargeable batteries self-discharge more rapidly than disposable alkaline batteries, especially nickel-based batteries; a freshly charged nickel cadmium (NiCd)