Basic concepts of power lithium batteries:
(1) Battery capacity
Battery capacity is an important performance parameter of a battery, which represents the amount of electricity the battery can release under certain conditions such as discharge rate, temperature, and termination voltage.
Battery capacity is represented by C, and its unit is ampere-hour (Ah) or milliampere-hour (mAh).
(2) Charging rate and discharging rate
This concept uses the ratio of battery rated capacity to charging time (discharging time) to compare the charging and discharging speeds of different batteries.
(3) Overcharging of the battery
Overcharging a battery means charging it excessively, which can damage the battery. When the charging process is nearing completion, i.e., when the battery is almost fully charged, only a small current should be used for low-rate charging. This is because low-current charging results in less polarization, less gas accumulation inside the battery, and sufficient time for heat dissipation.
(4) Charging termination voltage / discharging termination voltage
When a battery is fully charged, it means that the active material on the battery plates has reached saturation. Therefore, even if the battery continues to be charged at this point, the voltage will not rise further. This voltage is called the charging termination voltage. Similarly, the discharging termination voltage is the lowest voltage that can be reached during discharging.
(5) Battery internal resistance
The resistance measured at both ends of a battery is called the internal resistance of the battery.
