Room temperature precipitation of cobalt precursors for grape-like LiCoO2 particles productions

Abstract

Lithium ion batteries (LIBs) is currently the most promising energy storage device for technologies such as cellphones, gadgets, and electrical vehicles. Nowadays, LiCoO2 (LCO) type cells is still used due to its excellent performance even with high amount of cobalt. To reduce the overall production cost, a simple process with high scalability is proposed. In this study, a kilogram of LiCoO2 cathode materials were produced using room temperature cobalt crystallization of cobaltous solution. The effect of precipitating agents such as sodium hydroxide, oxalic acid and soda ash towards the material characteristics were deeply investigated. As obtained powders and products were characterized using XRD, FTIR, and SEM. Cobalt hydroxide, cobalt oxalate and cobalt carbonate were successfully synthesized based on XRD and FTIR study. Layered structure of LiCoO2 powders is confirmed by XRD study. SEM images of LCO products show a unique grape-like morphology with micron-sized secondary particles. Based on charge-discharge characteristics, the highest initial discharge capacity of 121 mAh/g is obtained by LCO from cobalt hydroxide with capacity retention of 24% after cycled for 230 cycles using 1C-2C-4C-8C-16C-30C current rates.