Stabilization of NASICON-Type Electrolyte against Li Anode via an Ionic Conductive MOF-Incorporated Adhesive Interlayer

Abstract

Sodium superionic conductor (NASICON)-type electrolytes with high ionic conductivity and moisture/air stability are essential for solid-state batteries. However, they generally suffer from poor electrochemical stability and insufficient contact against Li metal, causing severe performance degradation. To address this challenge, an ionic conductive metal–organic framework (MOF)-incorporated polymeric layer (denoted as ZCPL) is prepared and used as the coating layer of Li1.5Al0.5Ge1.5(PO4)3 (LAGP). As a protective layer, ZCPL can effectively prevent the redox reaciton between LAGP and Li metal, eliminating the formation of detrimental interphases and cracks upon battery cycling. The adhesive ZCPL can also infiltrate into the void/gaps of the LAGP surface, generating a firm connection with intimate contact. Besides, ZCPL with good ionic conductivity and a soft texture provides rich pathways for fast Li+ transport and ensures a uniform Li+ flow through the interface. Benefiting from ZCPL, both the Li symmerical cell and Li/LiFePO4 full cell show long-term cycling stability.