A Robust Dual‐Polymer@Inorganic Networks Composite Polymer Electrolyte Toward Ultra‐Long‐Life and High‐Voltage Li/Li‐Rich Metal Battery
Meng Yao, Qinqin Ruan, Yangyang Wang, Liyu Du, Qiongguang Li, Xu Lv, Ru‐Ji Wang, Haitao Zhang
Abstract
Abstract Composite polymer electrolytes (CSEs) that simultaneously possess superior electrochemical performances with robust mechanical properties are highly desired to the application of high‐energy lithium metal batteries. Herein, a novel dual‐polymer@inorganic network CSE (DNSE@IN) through a sequential nonhydrolytic sol‐gel reaction of tetraethoxysilane (TEOS) and the semi‐interpenetration of poly(vinylidene fluoride‐co‐hexafluoropropene)‐hexafluoropropylene (P(VDF‐HFP)) with poly(ionic liquid) (PIL) is proposed. DNSE@IN, which has a robust dual‐polymer@inorganic networks, not only has high ionic conductivity (0.53 mS cm −1 at 20 °C), but also exhibits an outstanding Young's modulus of 723.2 MPa. As a result, the DNSE@IN based Li/LiFePO 4 and Li/Li 1.17 Ni 0.27 Co 0.05 Mn 0.52 O 2 (Li‐rich) cells exhibit remarkable cycling stability from room temperature (RT) to 100 °C. As‐assembled Li/Li‐rich battery shows superior cyclability of 194.3 mAh g −1 after 70 cycles at 4.3 V under RT. Additionally, the scale‐up high‐voltage Li/Li‐rich pouch cells exhibit excellent cyclability (nearly 100% capacity retention after 93 cycles) and superior flexibility, safety at RT for potential practical applications. As such, the work of decoupling ionic conductivity and mechanical properties opens a novel route to develop novel CSEs for the construction of high‐energy lithium metal batteries.