Lamellar Ni-rich Co-free cathode material LiNi0.94Mn0.04Al0.02O2(NMA)was synthesized by a solid-phase sintering process,and the effects of different sintering temperatures on the crystal structure,microstructure and electrochemical performance of NMA cathode material were investigated.The results show that with excessively low sintering temperature,the crystallinity of the NMA cathode material is re-latively low and residual lithium is formed on the surface,while the extremely high sintering temperature leads to a deterioration of the lamellar structure and an increase in harmful side reactions on the electrode surface.The NMA-750 material synthesized at the optimal temperature of 750 ℃ demonstrates excellent particle morphology,minimal lithium-nickel mixing,and the most complete lamellar structure.Simultane-ously,the material exhibits the optimal electrochemical performance:its initial discharge specific capacity(3.0～4.5 V,1 C)is 199.5 mA·h/g,and the capacity retention rate reaches 79.04％after 100 cycles.It also has a discharge specific capacity of 147.6 mA·h/g at 5 C,presenting excellent rate performance.
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