Prilling and Coating Strategy to Synthesize High-Performance Spherical NaNi 0.4 Fe 0.2 Mn 0.4 O 2 Cathode Materials for Sodium Ion Batteries.

Low-cost sodium ion batteries are of great significance in large-scale energy storage applications. With its high energy density and simple synthesis process, layered transition-metal oxides have become one of the most likely sodium ion battery cathode materials to replace lithium ion batteries in the energy storage market. Here, we report a prilling and MoS 2 coating strategy to prepare the spherical cathode material. The spherical micronano particles shorten the diffusion path of Na + , restrain the complexity phase transitions, and enhance the tap density of the materials. In addition, the MoS 2 coating improves the electrical conductivity of the material and the structural stability of the cathode material in air. The initial specific discharge capacity is 148.4 mA h g -1 at 0.1 C, which can be maintained at 128.9 mA h g -1 after exposure to air for 10 days. This method dramatically improves the energy density and structural stability of the cathode material, which provides a new scheme for preparing high-performance sodium ion batteries.