Smart construction of intimate interface between solid polymer electrolyte and 3D-array electrode for quasi-solid-state lithium ion batteries

Interfacial issues have been the main obstacle to the development of solid-state batteries . In this work, we design a solid hybrid polymer electrolyte based on poly-(ethylene glycol) diacrylate and succinonitrile (PSSE) with a liquid state precursor. An intimate interface between PSSE and Li 4 Ti 5 O 12 @vertical graphene (LTO@VG) electrode with three-dimensional array structure is cleverly constructed by infiltrating fluid precursor of PSSE into vertical pores of LTO@VG followed by polymerization and solidification of PSSE. The quasi-solid-state LTO@VG//PSSE//Li and LiFePO 4 //PSSE//LTO@VG full cells exhibit superior electrochemical performance since the active materials are closely contacted by the conductive skeleton and ion-conductive electrolyte. The LTO@VG//PSSE//Li cells maintain 85.7% capacity retention after 400 cycles at 2 C and the LFP//PSSE//LTO@VG full cells still reach 99.0% capacity retention after 200 cycles at 0.5 C. This novel strategy for interface engineering paves the way for achieving high-performance solid-state batteries.