Synthesis of K[B 3 H 7 NH 2 BH 2 NH 2 B 3 H 7 ] for a K-ion solid-state electrolyte.

All-solid-state K batteries are ideal energy storage devices for grid-scale applications of renewable energies. A novel electrolyte K[B 3 H 7 NH 2 BH 2 NH 2 B 3 H 7 ] with weakly coordinating anions was synthesized. It has a high K + conductivity of 1.01 × 10 -4 S cm -1 at 75 °C, which is probably due to the increased electrostatic potential and size of the anions.