Functionalized polyoxometalates enable fast ion transport in solid-state batteries at room temperature.

The coupling of functionalized inorganic polyoxometalates with polymer electrolytes leads to considerably enhanced mechanical properties and faster ion transport (1.1 × 10 -4 S cm -1 ) at room temperature. The assembled Li/Li symmetric cell displays excellent stability in a 3000 h cycling test and a Li/LiFePO 4 cell exhibits superior cycling performance over 250 cycles.