Thermal Safety Characteristic Analysis of Large-Format Pouch Li-Ion Capacitors

Abstract

Lithium-ion capacitors (LICs), as the next generation of supercapacitors, combine the high power density and long cycle life of supercapacitors with the high energy density of lithium-ion batteries, presenting broad prospects for applications and becoming a focal point of research in academia and industry. Safety concerns regarding LICs, particularly the crucial issue of thermal safety, have garnered widespread attention. This study investigates the thermal abuse, electrical abuse, and mechanical abuse of 1100 F LICs, including overheating, overcharging, overdischarging, needling, extrusion, and short circuit tests, with real-time monitoring of temperature, gas emissions, and voltage to explore thermal runaway mechanisms. The results demonstrate that LICs remain safe under abusive conditions, with no occurrences of fire or explosion hazards.