Defect-Rich g-C<sub>3</sub>N<sub>4</sub> Nanosheets Catalyze PEO-Based Electrolytes to Create Fluorine-Rich Interfaces for High-Rate All-Solid-State Lithium-Metal Batteries
Xuan Zhou, Guobao Xu, Ke Huang, Zhihao Yan, Huan Hu, Xue Li, Gang Wang, Wenjuan Jiang, Liwen Yang, Jianyu Huang, Yunxiao Wang, Yaru Liang, Wei‐Hong Lai
Abstract
Although poly(ethylene oxide) (PEO) based electrolytes have attracted significant interest in all-solid-state lithium-metal batteries, the inferior ionic conductivity and poor interfacial incompatibility with lithium-metal have limited their practical application. Herein, nitrogen-defect-abundant g-C 3 N 4 (V N -CN) nanosheets are introduced into PEO to form composite solid electrolytes (V N -CN-PEO). The rich defects act as “electron traps” that effectively weaken Li + coordination with the anions and facilitate the decomposition of lithium salt, thus forming a LiF-rich interface with the Li anode. Therefore, the V N -CN-PEO exhibits reduced interfacial resistance with electrodes, improved Li + conductivity, and high mechanical strength. As a result, the Li symmetrical cells exhibit ultralong plating/stripping cycling for 3600 h at 0.1 mA cm –2 . The Li/V N -CN-PEO/LiFePO 4 cells deliver a capacity retention of 90% after 300 cycles at 0.2 C under 30 °C. Even the pouch cells show 81% capacity retention after 300 cycles at 0.1 C under 60 °C.