Improving Cyclability of 5 V Cathodes by Electrochemical Surface Modification

A simple electrochemical procedure is proposed for surface modification of cathode materials. A metal oxide-retaining layer deposited electrochemically on the electroactive material avoids its direct contact with the electrolyte. For 5 V cathodes, which are extremely oxidant at charged state, this action significantly enhances the cyclability. In addition, the own stability of the metal oxide-retaining layer deposited on the cathode surface has a significant effect on the cyclability, which can be enhanced by inducing a mechanical force during the electrodeposition process.