Mixed hydroxide precipitate-derived Li(Ni0.333Co0.333Mn0.333)O-2 as a cathode material for Li-Ion batteries

The mixed hydroxide precipitate (MHP), an intermediate product derived from the laterite ores, is the most abundant Ni source on the earth's crust. Herein, the potential use of MHP without purification for cathode synthesis is explored. The characteristics of NMC111 with 0 to 51% wt. MHP addition are compared in terms of crystal structure, morphology, and electrochemical properties. The typical layered cathode structure is preserved up to the 12.7 wt. % MHP addition. Rietveld refinement results confirm that the lattice parameters and Li-slabs were expanded as the amount of the MHP increased. The electrochemical results show that the first discharge capacity does not decrease until the 5.1 wt. % MHP addition. Furthermore, the long-term stability is improved by increasing MHP addition. While the pristine NMC keeps its 81% of first discharge capacity after 100 cycles, 5.1 wt. % MHP added sample retained 88%. Although the MHP addition tends to lower the rate capability of the cathode, the addition of MHP up to 2.6 wt. % does not compromise fast charge and discharge properties. EIS analyses show that the MHP addition reduces the charge transfer resistance of the cathode, which is a clue to enhanced Li-ion diffusivity.