Crosslinked network solid polymer electrolyte with self-healing ability and high stability for lithium metal battery

All-solid polymer electrolytes with good self-healing ability and high stability were designed based on polyoxyethylenebis(amine) (H2N-PEG-NH2) and 1,3,5-benzenetricarboxaldehyde through the Schiff base reaction. The effects of H2N-PEG-NH2 of various molecule weights on thermal and electrochemical properties were studied. It was found that shCLSPE-3400 electrolyte with appropriate PEG chain simultaneously exhibited good thermal stability, excellent self-healing ability and high mechanical strength, which is due to the introduction of crosslinked network structure and dynamic reversible bonds in the electrolyte. It also showed a high ionic conductivity of 4.8 x 10(-4) S cm(-1), wide electrochemical stability window (5.1 V) and good lithium ion transfer number (t(Li+) = 0.31) with an ethylene oxide/Li (+) ratio of 20:1 at 25 degrees C. In addition, a Li|shCLSPE-3400|LiFePO4 battery with shCLSPE-3400 as electrolyte was studied, and it showed good reversible specific capacity. Such electrolyte has potential for application in solid-state batteries, which will facilitate improvement in the safety performance of lithium metal batteries. (c) 2022 Society of Industrial Chemistry.