Abstract: In order to ensure the security level of the lithium battery energy storage industry and establish a scientific prevention and control technology for lithium battery fires, the research on the combustion characteristics and propagation law of the ternary lithium battery cell and module was carried out by overcharge. As the result shows, the combustion process of the ternary lithium battery could be divided into three stages: bulging, smoking, and jet burning.In the forin of jet fires high fire intensity and fast burning speed were both obverted during the combustion process and the maximum fire temperature was about 750 ℃. CO, SO2 and THC were generated as the ternary lithium battery going to thermal runaway. The CO concentration was the highest,exceeding 10-2. The THC concentration was about 2 × 10-3 and the SO2 concentration was the least. The thermal runaway expansion would happen under the condition of over change. The speed of thermal runaway expansion was relatively fast in the early stage of the fire and the interval time was only about 20 seconds, resulting the combustion of all battery call

Key words: ternary lithium battery, overcharge, combustion;flame propagation