What factors can cause thermal runaway of lithium iron phosphate batteries?

What is the cause of thermal runaway of lithium iron phosphate battery? The thermal runaway of lithium iron phosphate battery is mainly because the internal heat production is much higher than the heat dissipation rate, and a large amount of heat is accumulated inside the lithium battery, which causes a chain reaction, which causes the battery to catch fire and explode. (1) The cause of overheating of power lithium iron phosphate battery caused by thermal runaway triggered by overheating comes from the unreasonable selection and thermal design of the battery, or the temperature rise of the battery caused by the external short circuit, the loosening of the cable connector, etc. Two aspects of battery management are solved. From the perspective of battery material design, materials can be developed to prevent thermal runaway and block the reaction of thermal runaway; from the perspective of battery management, different temperature ranges can be predicted to mean different safety levels, so as to carry out hierarchical alarms. (2) Thermal runaway triggered by overcharge The thermal runaway triggered by overcharge refers to the lack of the safety function of the overcharge circuit in the lithium iron phosphate battery management system itself, which causes the battery's BMS to be out of control but still being charged. For this type of overcharge, the solution is to find the fault of the charger first, which can be solved by the full redundancy of the charger; secondly, it depends on whether the battery management is reasonable, for example, the voltage of each battery is not monitored. (3) Internal short circuit triggers thermal runaway battery manufacturing impurities, metal particles, charge and discharge expansion and contraction, lithium evolution, etc., may cause internal short circuits. This kind of internal short circuit occurs slowly and takes a very long time, and it is not known when thermal runaway will occur. If the test is carried out, the verification cannot be repeated. At present, experts all over the world have not found a process that can repeat the internal short circuit caused by impurities, and they are all under study. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.