Interfacial Manipulation via In Situ Constructed Fast Ion Transport Channels toward an Ultrahigh Rate and Practical Li Metal Anode

The successful substitution of Li metal for the conventional intercalation anode can promote a significant increase in the cell energy density. However, the practical application of the Li metal anode has long been fettered by the unstable solid electrolyte interface (SEI) layer on the Li metal surface and notorious dendritic Li growth. Herein, a stabilized SEI layer with in situ constructed fast ion transport channels has successfully been achieved by a robust In2S3-cemented poly(vinyl alcohol) coating. The modified Li metal demonstrates significantly enhanced Coulombic efficiency, high rate performance (10 mA cm(-2)), and ultralong life cycling stability (similar to 4900 cycles). The Li|LiCoO2 (LCO) cell presents an ultralong-term stable operation over 500 cycles at 1 C with an extremely low capacity decay rate (similar to 0.018% per cycle). And the Li|LCO full cell with the ultrahigh loading cathode (similar to 25 mg cm(-2)) and ultrathin Li foil (similar to 40 mu m) also reveals a prolonged cycling performance under the low negative-to-positive capacity ratio of 2.2. Furthermore, the Li|LCO pouch cell with a commercial cathode and ultrathin Li foil still manifests excellent cycling performance even under the harsh conditions of limited Li metal and lean electrolyte. This work provides a cost-effective and scalable strategy toward high performance practical Li metal batteries.

Automated summary

By improving the solid electrolyte interface and Li growth issues, the performance and cycling lifespan of Li metal batteries can be significantly enhanced.