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Reduced SE at High Discharge Currents: Batteries that are required to deliver their energy in short discharge times must have strongly ionizing electrolytes, e.g. lead-acid, nickel- cadmium and, for slightly longer discharge periods, silver-zinc and primary lithium systems. Reserve and thermal batteries were discussed earlier.
Poor Low-Temperature Performance: Most batteries give reduced voltage and Ah capacity at low temperatures, as shown in this figure for a lead-acid battery and here for a lithium-SO2 primary battery. Note particularly the effect on capacity of having both a low temperature and a high discharge current at the same time. At low temperatures, batteries are also less able to deliver high current peaks, e.g. for engine starting.
Self-Discharge and Storage Life: Self-discharging begins as soon as a battery is made and depends very much on the temperature. At high temperatures, internal leakage currents increase and chemical deterioration speeds up, causing more rapid self-discharge. Shelf life is often defined as the time for a battery to lose 15% of its initial charge. This can be up to 10 years for primary lithium-sulfur di batteries. Self discharge is always faster for rechargeable batteries, although these can be recharged. Most rechargeable systems, such as lead-acid, need to be stored in the charged state and the charge regularly topped-up, whilst others, such as NiCd, can be stored in any SOC. See the comparative rates of loss of capacity of different batteries as a function of temperature
Constancy of Discharge Voltage: Ideally, a battery should deliver a constant voltage until fully discharged, otherwise some form of voltage regulation may be required. Most secondary cells and lithium primary cells perform well in this respect. With zinc-carbon and, to a lesser extent, alkaline batteries, the voltage falls steadily during discharging (as mentioned previously, a falling voltage can be used to estimate the remaining capacity).
