Briefly describe the reason for thermal runaway of lithium battery

The thermal runaway of lithium batteries is mainly caused by the rise in the internal temperature of the battery. At present, the most widely used electrolyte system in commercial lithium batteries is a mixed carbonate solution of LiPF6. This type of solvent has high volatility, low flash point, and is very easy to burn. When the internal short circuit caused by collision or deformation, high-rate charging and discharging and overcharging, there will be a lot of heat, which will cause the battery temperature to rise. When a certain temperature is reached, it will cause a series of analytical reactions, which will destroy the thermal balance of the battery. When the heat released by these chemical reactions cannot be evacuated in time, it will aggravate the progress of the reaction and trigger a series of self-heating side reactions. The battery temperature rises sharply, that is, thermal runaway, which eventually causes the battery to burn, and even explode in severe cases. In general, the reasons for the thermal runaway of lithium batteries are mainly concentrated in the thermal instability of the electrolyte and the thermal instability of the electrolyte and the positive and negative coexisting systems. At present, from a general perspective, safety-type lithium batteries must take measures from two aspects: external management and internal design to control internal temperature, voltage, and air pressure to achieve safety goals. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: Analysis of several commonly used charging methods for lithium battery packs and the most suitable charging methods