Directly Using Li<sub>2</sub>CO<sub>3</sub> as a Lithiophobic Interlayer to Inhibit Li Dendrites for High-Performance Solid-State Batteries
Butian Chen, Jicheng Zhang, Tianran Zhang, Ruoyu Wang, Jian Zheng, Chong Liu, Xiangfeng Liu
Abstract
Garnet solid electrolytes have attracted great interest due to their wide electrochemistry window and high ion conductivity. However, the lithiophobic Li 2 CO 3 generated on the garnet surface results in a huge interfacial resistance and interface incompatibility. Herein, different from the extensive removal or conversion strategies, the Li 2 CO 3 on the surface of Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 (LLZTO) is directly used as a lithiophobic layer to suppress Li dendrite growth, and the lithophilic Li-In-F composite is used as the anode. The Li symmetrical half-cell with a Li 2 CO 3 interlayer is stably cycled for 6500 h without Li dendrite formation, a much longer time than for the half-cell without a Li 2 CO 3 interlayer (2334 h), showing a much higher interfacial stability. Moreover, the full cell based on LiFePO 4 and LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode shows a stable cycling performance and high rate capability (LiNi 0.8 Co 0.1 Mn 0.1 O 2, 94%@100th cycle@1C; LiFePO 4, 90%@500th cycle@2C). This study provides a distinct way of converting disadvantages into advantages and solving the Li|LLZTO interfacial issues.