Organic electrolyte-based rechargeable zinc-ion batteries using potassium nickel hexacyanoferrate as a cathode material

A reversible zinc-ion battery system in organic electrolyte was characterized using the cubic Prussian blue (PB) analog K0.86Ni[Fe(CN)6]0.954(H2O)0.766 as the cathode. The organic electrolyte system provides a much higher zinc cycling efficiency (>99.9%) than conventional aqueous systems (<80%). The inserted zinc ions in the cathode were located at the center of the large interstitial cavity, as confirmed by Fourier electron density analysis.238