Octahedral nano-particles constructed LiNi0.5Mn1.5O4 microspheres as high-voltage cathode materials for long-life lithium-ion batteries

摘要

The spinel LiNi0.5Mn1.5O4 (LNMO) cathode materials suffer from severe capacity fade during the charge-discharge process, which is caused by the instability of material structure under high voltage. Herein, a novel LNMO microsphere is prepared via simple co-precipitation method. The SEM images show that the LNMO spheres are constructed by many octahedral nano-particles. The structure stability of the LNMO cathode materials is improved so that the as-prepared LNMO cathode materials exhibit excellent electrochemical performance. It delivers a discharge capacity of 133.29 mA h g(-1) at 0.2 C. Even the specific capacity still remains 127.46 mA h g(-1) and the capacity retention rate is up to 95.6% after 300 cycles at 0.2 C. It is mainly attributed to the fact that the as-prepared LNMO materials expose the (111) crystal plane with the lowest surface energy.