What is the capacity of a battery

The capacity of the battery is divided into rated capacity and actual capacity. The rated capacity of a battery means that the design and manufacture of the battery specify or guarantee that the battery should discharge the minimum amount of electricity under certain discharge conditions. The IEC standard specifies that the rated capacity of a nickel-cadmium or nickel-hydrogen battery is the quantity of electricity discharged when the battery is charged at 0.1 C for 16 hours and then discharged at 0.2 C to 1.0 V at 20 ℃ ± 5 ℃, which is expressed as C5. For lithium-ion batteries, the rated capacity is the amount of electricity released when they are charged for 3 hours at room temperature and under the charging conditions of constant current (1 C)-constant voltage (4.2 V) control, and then discharged from 0.2 C to 2.75 V, while the actual capacity of the battery refers to the actual amount of electricity released by the battery under certain discharge conditions. It is mainly affected by the discharge rate and temperature (so strictly speaking, the battery capacity should indicate the charging and discharging conditions). The unit of battery capacity is Ah, mAh (1Ah = 1000 mAh).