Solvent-controlled the morphology and electrochemical properties of LiNi0.5Mn1.5O4 derived from metal-organic frameworks

The spinel LiNi0.5Mn1.5O4 cathode material was synthesized via a metal-organic frameworks (MOFs) method followed by high-temperature calcination. The effects of the solvent molecular chain length on the structure, morphology, and electrochemical properties of the MOF precursors and LiNi0.5Mn1.5O4 materials were investigated. The results show that the content of Mn3+, the size of MOF precursors, and LiNi0.5Mn1.5O4 particle gradually decreases with the increasing of solvent molecular chain length. Among them, the LNMO-EG sample exhibits superior electrochemical performance, the discharge capacity retention of 96.1% after 200 cycles at 1C rate, at a high rate of 5C, it still delivers a capacity of 120.8 mAh g(-1) and capacity remains 85.2% after 500 cycles. These improvements might be due to the synergistic effect of moderate particle size, high Mn3+ content, and low impurity content, which avoids material agglomeration during long-term cycling and promotes the diffusion of Li+ during the interaction/deinteraction process.