In-situ cathode coating for all-solid-state batteries by freeze-drying technology

Abstract

All solid-state batteries (ASSBs) are considered in the next generation of energy storage, but their active material ratio is low and cathode interface reactions are severe.To overcome these two challenges, a layer of fast ion conductor Li3InCl6 is in-situ synthesized to realize uniform coating on LiCoO2 surface by freeze drying technology, which effectively improves active material proportions/ion transportation capability in the cathode, and prevents interfacial degradation between sulfide solid electrolyte and LiCoO2. The resultant Li-anode ASSBs show excellent electrochemical performances, including 7000 cycles at 20 C (9.4 mA/cm2), unprecedented current rates of 70 C and high loading of 15 mAh/cm2 (110 mg/cm2). The ASSB achieved an energy density of 340 Wh/kg. These encouraging results make future practical applications of high-energy-density ASSB with high cathode loadings and fast-charging capabilities possible.