Highly Stable Organic Molecular Porous Solid Electrolyte with One‐Dimensional Ion Migration Channel for Solid‐State Lithium−Oxygen Battery

Abstract

AbstractSolid‐state lithium−oxygen (Li−O2) batteries have been widely recognized as one of the candidates for the next‐generation of energy storage batteries. However, the development of solid‐state Li−O2 batteries has been hindered by the lack of solid‐state electrolyte (SSE) with high ionic conductivity at room temperature, high Li+ transference number, and the high stability to air. Herein, the organic molecular porous solid cucurbit[7]uril (CB[7]) with one‐dimensional (1D) ion migration channels is developed as the SSE for solid‐state Li−O2 batteries. Taking advantage of the 1D ion migration channel for Li+ conduction, CB[7] SSE achieves high ionic conductivity (2.45 × 10−4 S cm−1 at 25 °C). Moreover, the noncovalent interactions facilitated the immobilization of anions, realizing a high Li+ transference number (tLi+ = 0.81) and Li+ uniform distribution. The CB[7] SSE also shows a wide electrochemical stability window of 0–4.65 V and high thermal stability and chemical stability, as well as realizes stable Li+ plating/stripping (more than 1000 h at 0.3 mA cm−2). As a result, the CB[7] SSE endows solid‐state Li−O2 batteries with superior rate capability and long‐term discharge/charge stability (up to 500 h). This design strategy of CB[7] SSE paves the way for stable and efficient solid‐state Li−O2 batteries toward practical applications.