Early Detection for Li-Ion Batteries Thermal Runaway Based on Gas Sensing

During battery storage and transport, thermal runaway is a critical issue for battery safety. For cells stored in a 55 gallon (0.208 m3) drum, a single cell thermal runaway can heat up neighboring cells, causing a chain reaction of thermal runaway propagation. It is important to detect a thermal runway event before it propagates to other cells and becomes difficult to extinguish. This paper presents a Li-ion batteries thermal runaway early detection method based on gas sensing. By monitoring CO2 concentrations, which is produced at early stage of battery thermal runaway, early detection at cell failures are possible. The simulation shows much faster response of gas sensing comparing to conventional surface temperature sensing. While the surface temperature sensing approach fails to detect thermal runaway before it propagates to other cells, the gas sensing approach detects the event ahead of thermal runaway propagation.