Influence of non-stoichiometric binary titanium oxides addition on the electrochemical properties of the barium ferrate plastic-bonded cathode for super-iron battery

The solid salts of the ferrate anion might offer significant advantages over conventional materials used as cathodes because of the three electron transfer associated with the reduction of Fe(VI) to Fe(III). In the present study, we try to improve the performance of the electrochemically synthesized barium ferrate cathode using non-stoichiometric binary titanium oxides: titanium monoxide (TiOx) and Magneli phases (TinO2n-1) addition performed throughout fabrication of plastic bonded cathode. It is shown that the addition of conductive Magneli phase materials into active material improves the performance of a cathode in terms of specific capacity, reversibility, and more positive equilibrium potential compared to BaFeO4 - based cathodes. It is believed that Magneli phase material enhances connectivity of the active BaFeO4 material and acts as reinforcement to the active mass thereby aiding retention of feature and porosity during cycling improving the reaction kinetics of the electrode. Also, our preliminary results demonstrate that the porous plastic bonded thin foil electrodes based on electrochemically synthesized barium ferrate can be considered in spiral wound battery geometry for higher rate capability. (C) 2017 Elsevier Ltd. All rights reserved.