Metal‐Organic Coordination Enhanced Metallopolymer Electrolytes for Wide‐Temperature Solid‐State Lithium Metal Batteries

The practical application of polymer electrolytes is seriously hindered by the inferior Li+ ionic conductivity, low Li+ transference number (tLi+), and poor interfacial stability. Herein, a structurally novel metallopolymer is designed and synthesized by exploiting a molybdenum (Mo) paddle‐wheel complex as a tetratopic linker to bridge organic and inorganic moieties at molecular level. The prepared metallopolymer possesses combined merits of outstanding mechanical and thermal stability, as well as a low glass transition temperature (Tg < –50 °C). Based on this metallopolymer, an advanced metal‐organic coordination enhanced metallopolymer electrolyte (MPE) is developed for constructing high‐performance solid‐state lithium metal batteries (LMBs). Due to the unsaturated coordination of Mo atoms, the uniformly distributed Mo‐polyoxometalates (Mo‐POMs) in metallopolymer skeleton can effectively bis(fluorosulfonyl)imide anions (FSI‐) and promote the dissociation of Li salts. Moreover, dynamic metal‐organic coordination bonds endow the MPE with re‐processability and self‐healing, enabling it to accommodate electrode volume changes and maintain good interfacial contact. Consequently, the MPE achieves a competitive ionic conductivity of 0.712 mS cm‐1 (25 °C), a high tLi+ (0.625), and a wide electrochemical stability window (> 5.0 V). This study presents a unique MPE design based on metal‐organic coordination enhanced strategy, providing a promising solution for developing wide‐temperature solid‐state LMBs.