Effects of different charging and discharging modes on thermal behavior of lithium ion batteries

The heat release law of lithium ion battery during different cycles of charging-discharging rate was studied by the LAND testing device. Studies have shown that: When charging at 0.5C and discharge cycles at 0.5C, 1C, 2C, and 3C, respectively, the battery cycle heat dissipation increases with the increase of the discharge rate, and the temperature rise ratio of the battery after the 3C cycle is 0.5C, 1C, 2C is higher by 30.8 °C, 21.4 °C, and 9 °C; 0.5C, 1C, 2C, 3C rechargeable battery temperature rise after 1C discharge and 0.5C, 1C, 2C, 3C charge cycles, respectively. The heights are 13.8 °C, 18.1 °C, 37.6 °C, and 44.3 °C, respectively; when the battery is cycled at a 3C charging-discharging rate, the battery voltage suddenly changes to 0 V after the 2nd cycle; when the charge current and discharge current are relatively small, the heat generated during low-rate charging high-rate discharge cycles is larger, and when the charge current and the discharge current are relatively large, the heat generated at the low-rate charging high rate discharge cycle is smaller than the high-rate charging low-rate discharge cycle. The research obtained the heat dissipation data of lithium-ion batteries under different charging-discharging rates, which provided an important basis for the safe operation of lithium-ion batteries.