Enhanced cycle performance of a Na/NiCl2 battery based on Ni particles encapsulated with Ni3S2 layer

Nickel particles with different contents of Ni 3 S 2 surface layer were prepared for their application as cathode materials in Na/NiCl 2 batteries . The surface modification of nickel particles is found to prevent their growth and battery degradation during cycling. The optimum level of surface modification was determined by electrochemical tests and morphology characterization. Excessive Ni 3 S 2 layer seems to cause particle aggregation resulting in low reversible capacity. The capacity of the cell with optimum level of Ni 3 S 2 surface modification layer after 50 cycles is about 4 times greater than that without Ni 3 S 2 surface modification layer.