Real-time temperature measurement with fiber Bragg sensors in lithium batteries for safety usage

In this work, fiber Bragg grating (FBG) sensors are integrated in lithium batteries to measure temperature variations. In situ calibration of the FBG sensors against a co-located thermocouple shows a linear response. The thermal behavior of lithium batteries is real-time recorded by FBG sensors, during the batteries operation under normal and abnormal conditions. In spite of the small cathode mass and a low current, temperature variations of 0.1 °C are detected. The sensors also exhibit good thermal response to dynamic loading when compared with the thermocouple. The thermal stabilities of four kinds of cathode materials are estimated using FBGs testing results.