Operando Temperature Monitoring Through Optical Fiber Sensor in Lithium-Ion Battery

The battery temperature evolution is closely related to the charging and discharging process, and it is important to improve the battery management. This work presents a temperature monitoring of the internal and external of the pouch cell, and different temperature characteristic points of the pouch cell under long-term cycling conditions are discussed in detail. Considering the electrochemical corrosion inside the cell, the fiber Bragg grating is selected as the temperature sensor, and the results demonstrate that the internal temperature must be closely monitored, especially for the high discharge rates.