Surface-supporting method of micropad deposition onto LiCoO₂ epitaxial thin films to improve high C-rate performance

High-speed rechargeable Li ion batteries are in strong demand. Two methods have been reported to improve the high-speed rechargeability of electrodes: reducing particle size and introducing a surface support. However, the effectiveness of the latter could not be directly compared among reports due particle size differences from study to study. Our previous report revealed that Li⁺ motion under high-speed chargedischarge conditions is accelerated around a surface-supporting material, an electrode, and an electrolyte interface. In this study, we prepared epitaxial LiCoO₂ thin films with micropads of various kinds of materials and evaluated the high-speed rechargeability of each.