Herein, a composite polymer electrolyte with a viscoelastic and nonflammable interface is designed to handle the contact issue and preclude Li dendrite formation. The composite polymer electrolyte (cellulose acetate/polyethylene glycol/Li 1.4 Al 0.4 Ti 1.6 P 3 O 12 ) exhibits a wide electrochemical window of 5 V (vs Li + /Li), a high Li + transference number of 0.61, and an excellent ionic conductivity of above 10 −4 S cm −1 at 60 °C. In particular, the intimate contact, low interfacial impedance, and fast ion-transport process between the e...
