Coordination‐driven crosslinking electrolytes for fast lithium‐ion conduction and solid‐state battery applications

Rechargeable batteries paired with lithium (Li) metal anodes are considered to be promising high‐energy storage systems. However, the use of highly reactive Li metal and the formation of Li dendrites during battery operation would cause safety concerns, especially with the employment of highly flammable liquid electrolytes. Herein, a general strategy by engineering coordination‐driven crosslinking networks is proposed to achieve high‐performance solid polymer electrolytes. Through the coordination of metal–organic polyhedra (MOPs) with cellulose‐based copolymers, the Li+‐conducted hypercrosslinked MOP (CHMOP‐Li) polymer network is capable of enabling the rapid transport of Li+. In addition to the high Li+ conductivity (1.02×10−3 S cm−1 at room temperature), CHMOP‐Li electrolyte also exhibits a high Li+ transference number (0.75) and a wide electrochemical stability window. Benefiting from the thermally stable and mechanically strong CHMOP‐Li electrolyte film, the short‐circuiting of the symmetric batteries is prevented even after 3200 h of cycling and a high specific energy of 300 Wh kg−1 is achieved for the Li–metal battery. The solid‐state Li–air batteries fabricated with CHMOP‐Li electrolyte also show good cycling performance (500 cycles) and high discharge capacity (15740 mAh g−1). The proposed coordination‐driven crosslinking strategies offer an alternative route to design high‐performance next‐generation sustainable battery chemistries.