Preparation of nanocrystalline LiMn_2O_4 thin film by electrodeposition method and its electrochemical performance for lithium battery

摘要

The LiMn_2O_4 thin films composed of nanoparticles were synthesized by sintering electrodeposited Mn_3O_4 precursor on the Au substrate, and the electrochemical properties were investigated. The electrochemical performance was dependent on the film thickness. For the thinner LiMn_2O_4 films, cycling in the voltage range of 4.3 V-3.4 V resulted in superior rate performance, that is almost 100% of discharge capacity compared with that at 20 times of discharge current density, and good stability without capacity loss until 500 cycles. CV and EIS measurements revealed that LiMn_2O_4 thin film has good electric contact with substrate and high lithium diffusion coefficient of 10~(-9)-10~(-11) cm~2 s~(-1) could be obtained.