A Rapid Deposition of Lithium Cobalt Oxide Thin Film As Cathode By Atmospheric Plasma Spraying Method

Abstract

Lithium ion batteries (LIB) have been widely-applied for decades. For safety concerns, all parts of the batteries especially electrolyte tend to be solid state rather liquid state. This research was conducted by assembling all-solid-state batteries (ASSB). Cathode, LiCoO2 (LCO), was fast deposited by atmospheric plasma spraying (APS) method on stainless steel. The cathode film could be rapidly formed in few minutes and the thickness of LCO would reach to 10~40 μm. After heat treatment for few hours, the roughness of the cathode film was still high and could not be eliminated. High roughness of the cathode would reduce the cycle life or fail the battery. In order to assure that the batteries could work properly with reliable capacity, smoother surface of LCO thin films would be required. Hence, aerosol deposition (AD) method was conducted after APS method to solve this issue. By AD, surface-modified LCO film was produced and then assembled into ASSB. Owing to AD, the roughness of the LCO thin film could be eliminated significantly to improve the performance of LIB. The electrochemical characterization of ASSB showed the first discharge capacity of 796 μAh and the capacity retention was achieved 100% after 100 charge-discharge cycles between 4.2V and 3V at 0.25C.