A self‐healing polymer electrolyte based on the Diels–Alder reaction in lithium‐ion batteries

Abstract

In lithium‐ion batteries, the polymer electrolyte was susceptible to mechanical damage from external stimuli or internal expansion caused, which in turn affected the performances of the batteries. The thermally reversible self‐healing gel polymer electrolyte (DASHPE) based on the Diels–Alder reaction was prepared to solve the above problems. The DASHPE electrolytes exhibited good flexibility and self‐healing ability, achieving self‐healing at 80°C for 30 min. Furthermore, the DASHPE electrolyte exhibited excellent thermal stability and could withstand temperatures above 300°C. Additionally, it had a wide electrochemical window (about 5 V) and good electrochemical performances. Serving as the electrolyte in lithium‐ion batteries, DASHPE‐2 showed an initial specific capacity of 133.11 mAh g−1 at 0.1 C. The DASHPE electrolyte was expected to be a candidate material for self‐healing battery.