Electrolyte flame retardants are a very effective way to reduce the risk of thermal runaway of batteries, but these flame retardants often have a serious impact on the electrochemical performance of lithium ion batteries, so it is difficult to use in practice. In order to solve this problem, of the university of California, San Diego, YuQiao team [1] with the method of capsule packaging will flame retardant DbA (dibenzyl amine) stored in the interior of the micro capsule, scattered in the electrolyte, in normal times will not impact on the performance of lithium ion batteries appeared, but when the cells from being destroyed by external force such as extrusion, The flame retardants in these capsules are then released, poisoning the battery and causing it to fail, thereby alerting it to thermal fuyez. In 2018, YuQiao's team [2] utilized the above technology again, using ethylene glycol and ethylenediamine as flame retardants, which were encapsulated and inserted into the lithium ion battery, resulting in a 70% drop in the maximum temperature of the lithium ion battery during the pin pin test, significantly reducing the risk of thermal control of the lithium ion battery.