A Robust Dual-Polymer@Inorganic Networks Composite Polymer Electrolyte Toward Ultra-Long-Life and High-Voltage Li/Li-Rich Metal Battery

摘要

Composite polymer electrolytes (CSEs) that simultaneously possess superiorelectrochemical performances with robust mechanical properties are highlydesired to the application of high-energy lithium metal batteries. Herein, anovel dual-polymer@inorganic network CSE (DNSE@IN) through a sequentialnonhydrolytic sol-gel reaction of tetraethoxysilane (TEOS) and the semi-interpenetrationof 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 ionicconductivity (0.53 mS cm~(?1) at 20 ℃), but also exhibits an outstanding Young’smodulus of 723.2 MPa. As a result, the DNSE@IN based Li/LiFePO_4 andLi/Li_(1.17)Ni_(0.27)Co_(0.05)Mn_(0.52)O_2 (Li-rich) cells exhibit remarkable cycling stabilityfrom room temperature (RT) to 100 ℃. As-assembled Li/Li-rich battery showssuperior 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, safetyat RT for potential practical applications. As such, the work of decoupling ionicconductivity and mechanical properties opens a novel route to develop novelCSEs for the construction of high-energy lithium metal batteries.