Polymer lithium-garnet interphase for an all-solid-state rechargeable battery

Abstract Garnet electrolytes having a room-temperature Li + conductivity of 10 −3 S cm −1 suffer from adsorbents that prevent wetting by a lithium anode; formation and growth of lithium-anode dendrites into grain boundaries and a huge interfacial resistance to anode plating and stripping result. A thin coating of a garnet surface by a Li + -conducting polymer with a transfer number of 0.9 is shown to suppress dendrite formation and to reduce greatly the interfacial resistance. A coulombic efficiency near 100% with a single thin polymer coat can provide Li/garnet/LiFePO 4 all-solid-state cell with a long cycle life.