Synthesis of Li-Ion Battery Cathode Material: Conversion of Cheap Mixed Hydroxide Precipitate to High Performance LiNi_0.5Mn_0.3Co_0.2O₂

Abstract

The cathode material of the lithium-ion battery in this study is LiNi0.5Mn0.3Co0.2O2 (NMC532) with a mole ratio of Ni, Mn, and Co respectively 5:3:2. The purpose of this research was aimed for direct using of MHP as the nickel source to NMC532 as cathode material can greatly reduce the overall production cost due to shorter supply chain of nickel which is beneficial for commercialization of cathode material. The Mix Hydroxide Precipitate (MHP) was leached by acetic acid to earn nickel acetate. Then, to make NMC532 by co-precipitation method, the nickel acetate was reacted with MnSO4.H2O, CoSO4.7H2O, and C2H2O4.2H2O. Based on the XRD and FTIR analysis, NMC532 exhibited a high crystalline layered structure with no observable impurity peaks even with the presence of impurities such as other metals or organic groups contained in MHP. SEM images showed homogenous particles with polycrystalline morphology. Charge-discharge analysis performed in cylindrical cell type 18650 showed promising results such as excellent cycle performances with specific charge capacity 179.14 mAh/g and specific discharge capacity 111.19 mAh/g. The rate ability could perform stable in every current density (0.1C, 1C, 4C, 8C, and 16C) and retested again in 0.1C with the initial capacity 90.89 mAh/g. The overall process can be considered as cheap and economically attractive to be adapted at industrial scale.