Abstract: This study focuses on the research of tactile sensing technology in the safety monitoring of thermal runaway in lithium-ion batteries for energy storage applications. A 52 Ah prismatic LFP (Lithium Iron Phosphate) battery is selected as the subject of investigation. Thermal runaway in individual cells and battery modules is triggered using a heating plate, and a combination of force, electrical, and thermal real-time monitoring methods is employed to thoroughly analyze the thermal runaway processes at both the single-cell and module levels. In the single-cell thermal runaway experiment, when the internal short circuit occurs due to the gradual increase in battery temperature caused by the heating plate, the swelling force sharply increases at 112 seconds, preceding noticeable changes in voltage and temperature by 8.9 min. Further extending to the module-level thermal runaway experiment, during the phase where heat propagation leads to thermal runaway in adjacent cells after triggering the end cell, the swelling force exhibits rapid growth even before any significant temperature and voltage characteristics appear, identifying signs of thermal runaway approximately 6.0 min earlier than voltage and temperature measurements. This effectively demonstrates the importance of incorporating force dimension data monitoring in enhancing the early warning capability for thermal runaway in energy storage lithium-ion batteries.

Key words: lithium iron phosphate battery, thermal runaway propagation, heat transfer, temperature variation, voltage response, mass variation