Lithium ion batteries are a type of rechargeable batteries that use graphite or other carbon materials as negative electrodes and lithium-containing compounds as positive electrodes. During the charging and discharging process, there is no metal lithium, only lithium ions, so lithium batteries are also called lithium ion batteries. .

Lithium-ion battery has high working voltage, stable discharge curve, large energy density (weight specific energy is 110~160Wh/kg), small size, light weight, and long cycle life (after 500 cycles, the capacity remains above 80%); No memory effect, small self-discharge; wide operating temperature range, (charging 0~45℃, discharging -20~60℃); green and environmentally friendly, free of toxic metal elements such as lead, cadmium and mercury.

According to the different materials of the positive electrode, lithium ion batteries are divided into lithium cobalt oxide batteries, lithium manganese ion batteries, ternary material lithium ion batteries, and lithium iron phosphate batteries.

According to the different shapes of batteries, lithium-ion batteries are divided into cylindrical lithium-ion batteries, square lithium-ion batteries, and soft-pack polymer lithium-ion batteries.