Interrelation between discharge capacity and charge coefficient of redox potential in tertiary batteries made of transition metal hexacyanoferrate

Abstract

Abstract We fabricated eight tertiary batteries made of transition metal hexacyanoferrates and evaluated thermally-induced voltage (V cell) and discharge capacity (Q cell) per unit weight of the total active material contained in the cathode and anode. V cell and Q cell are reproduced by the values ( V cell calc and Q cell calc ) calculated from temperature (α) and charge (β) coefficients of the redox potential (V) of cathode and anode materials. Reflecting small −β of Na x Zn3[Fe(CN)6]1.967.2H2O (ZnHCF), Q cell for Na x Co[Fe(CN)6]0.873.4H2O/ZnHCF cell reaches 4.0 mAh g−1 between 20 °C and 40 °C.