Diffusion-Free All-Solid-State Batteries Enabled by an Ionic/Electronic Dual-Conductive Anode

Silicon(Si)is one of the most promising anodes for enabling all-solid-state batteries(ASSBs)with high energy density and safety.However,the tremendous volume change and sluggish kinetics result in poor electrochemical performance.Herein,we proposed an ionic/electronic dual-conductive material of Li_(x)Si as a diffusion-rapid and all-active anode for ASSBs.Compared with pure Si anode,the as-fabricated Li_(x)Si showed dramatic promotions of 35 times electronic and 400 times ionic conductivities.The three-dimensional(3D)ionic-electronic transport system of Li_(x)Si enabled rapid kinetics and uniform volume change of electrode materials in the whole electrode,corresponding to a lower volumechange rate.As a result,the ASSBs with LiCoO_(2)cathode exhibited a reversible discharge capacity of 154.4 mAh g−1,corresponding to an initial Coulombic efficiency of 97.3%.Besides,the batteries delivered a high rate capacity of 99.3 mAh g^(−1)at 2 C and long-term cycle stability of 94.0%after 800 cycles at 1 C,which was much better than the pure Si anode.This study sheds light on a new understanding of the importance of ionic conductivity for Si-based anode and might help inspire the design of advanced anode materials for ASSBs.