Potassiation and Depotassioation Properties of Sn₄P₃ Electrode in an Ionic-Liquid Electrolyte

Abstract

K-ion battery is a potential candidate as a next-generation battery with a high energy density, long cycle life, and high safety. To commercialize the battery, the improvement of safety is absolutely essential. We apply a nonflammable ionic-liquid electrolyte to a Sn₄P₃ electrode as negative-electrode for K-ion battery. The electrode achieves the excellent cycling performance with a discharge capacity of 365 mA h g⁻¹ over 100 cycles in the ionic-liquid electrolyte. Rate capability in the ionic-liquid electrolyte is almost the same as that in the organic-liquid electrolyte.