New Energy Vehicle Solutions

Thermal-related problems of batteries are the key factors that determine their performance, safety, life and cost of use. Firstly, the temperature level of lithium ion batteries directly affects their energy and power performance in use. When the temperature is low, the available capacity of the battery will decay rapidly. Charging the battery at an excessive low temperature (such as below 0 C) may cause instantaneous overcharge of voltage, resulting in internal lithium precipitation and short circuit. Secondly, the thermal-related problems of lithium-ion batteries directly affect the safety of batteries. Defects in the manufacturing process or improper operation in the use process may cause partial overheating of batteries, and then cause chain exothermic reactions, resulting in serious thermal runaway incidents such as smoke, fire and even explosion, threatening the safety of vehicle drivers. In addition, the working or storage temperature of lithium ion batteries affects their service life. The suitable temperature of the battery is between 10 ~30 C, too high or too low temperature will cause the rapid decay of the battery life. Large-scale power batteries make the ratio of surface area to volume relatively smaller, and the internal heat of batteries is not easy to dissipate. It is more likely that the internal temperature is uneven and the local temperature rise is too high, which further accelerates the battery attenuation, shortens the battery life and increases the total cost of ownership of users.