Melt-Infusion-Induced Electrolyte Surface Coating Stabilized Sulfide-Based All-Solid-State Lithium Metal Batteries
Shuxian Zhang, Qingyu Li, Jing Gao, Renbo Liu, Xiaobo Jiang, Shijian Xiong, Chengxiang Wang, Zhiwei Zhang, Yinghua Qiu, Yuanchang Shi, Longwei Yin, Rutao Wang
Abstract
Sulfide-based all-solid-state lithium metal batteries (ASSLBs) are a potentially safe and high-energy electrochemical storage technology. The continuous interfacial degradation within sulfide solid-state electrolytes (SSEs) and Li metal however hinders Li + transport and induces inhomogeneous Li deposition. Herein, we propose a melt-infusion method to introduce lithium trifluorosulfonylimide (LiTFSI) on Li 5.5 PS 4.5 Cl 1.5 (LPSCl) particles as an artificial coating. This artificial coating can mitigate interfacial side reactions and induce the generation of the LiF/Li 3 N-rich solid electrolyte interphase (SEI). The combined experimental and theoretical results reveal that this LiF/Li 3 N-rich SEI has the merits of accelerating Li + transport and suppressing Li dendrites. It enables the Li anode to reach a high critical current density (CCD) up to 3.1 mA cm –2 . In conjunction with coated sulfide SSEs, Li-symmetric cells operate stably for 900 h at 2 mA cm –2 . The ASSLBs using this coated sulfide SSEs can reversibly charge/discharge at 2C over 1000 cycles with a 90.2% capacity retention. A high LiCoO 2 loading of 28.5 mg cm –2 is further demonstrated in this ASSLB with cycling stability over 100 cycles at 0.2C.