Empowering Quasi-solid Electrolyte with Smart Thermoresistance and Damage Repairability to Realize Safer Lithium Metal Batteries.

Thermal runaway, a complex chemical/electrochemical heat breakout process caused by complex abuse conditions, remains a big issue to significantly hinder further practical application of lithium batteries. Here we design and fabricate a smart thermoregulatory and self-healing gel electrolyte (TRSHGE) by cross-linking phase-transition chains to polymer networks through reversibly dynamic interactions while maintaining the desirable electrochemical performance. Impressively, on the one hand, the phase-transition chains with endothermic effects can efficiently accommodate the heat accumulation, enabling lithium batteries to work safely and normally even up to 80 °C. On the other hand, the dynamic covalent boronic eater bonds and hydrogen bonds endow the TRSHGE damage repairability upon mechanical shock even at the nail penetration test. Such smart electrolyte with thermoresistance and damage repairability indicates significant technological advancement toward the safe commercial application of lithium batteries, even great potential to develop other functional batteries beyond the lithium-based systems discussed herein.