Nanocomposite All‐Solid‐State Polymer Electrolyte for High‐Performance Lithium Batteries

Abstract An inorganic‐polymeric hybrid all‐solid‐state electrolyte (SSE) composed of chemically modified nano‐silica, linear poly(trifluoroethyl methacrylate)‐co‐poly(poly(ethylene glycol) methyl ether methacrylate copolymer (PTFEMA‐co‐PPEGMA or LCP) and lithium salt is prepared and used in lithium‐ion batteries (LIBs) for the first time. Nano‐silica is transformed to SiO 2 ‐SH via esterification reaction. Then, SiO 2 ‐PEGMA is synthesized through click chemistry of SiO 2 ‐SH and PEGMA. The compatibility of the nano‐SiO 2 and the LCP can be effectively improved due to the excellent dispersibility of the chemically modified nano‐SiO 2 in the polymer matrix. As a result, the hybrid SSE has good thermal stability, excellent film‐forming ability. Furthermore, the hybrid SSE shows superior comprehensive electrochemical properties, which makes the corresponding LiFePO 4 /Li cells have good cycling performance (the discharge capacity reaches 144 mAh g −1 at 0.3 C) and rate capability (90 mAh g −1 is reached at 1 C). Thus, the hybrid electrolyte can be a powerful SSE for high‐safety and high‐performance LIBs.