Surface coating with Li3BO3 protection layer to enhance the electrochemical performance and safety properties of Ni-rich LiNi0.85Co0.05Mn0.10O2 cathode material

To enhance the electrochemical properties and safety performance of Ni-rich cathode materials for Lithium-ion batteries, a typical wet chemical method followed by high temperature sintering was applied to make the Li + conductive Li 3 BO 3 with different mass fractions cover on the surface of Ni-rich LiNi 0.85 Co 0.05 Mn 0.10 O 2 . And the influence of the coating layer on the phase, crystal structure, particles morphology and electrochemical properties during cycling were systematically studied. The physicochemical characterization results suggested a coating layer with a thickness of 10–15 nm formed by Li 3 BO 3 nanoparticles was equably adhered on the surface of cathode particles, without causing obvious variation of the crystal structure and morphology. The electrochemical measurement indicated the suitable amount of Li 3 BO 3 coating layer could effectively enhance the rate capability, discharge ability at low temperature and cycling performance of LiNi 0.85 Co 0.05 Mn 0.10 O 2 due to the increased Li + diffusion rate and restrained side reaction from electrode with electrolyte. Particularly, the 2 wt% Li 3 BO 3 coated LiNi 0.85 Co 0.05 Mn 0.10 O 2 respectively delivered a capacity retention of 91.4% and 90.1% at 25 °C and 45 °C after 300 cycles, and the pristine one merely retained a capacity retention of 83.9% and 80.4% accordingly. Besides, the pouch full batteries with 2 wt% Li 3 BO 3 coated LiNi 0.85 Co 0.05 Mn 0.10 O 2 cathode demonstrated the obvious enhancement on the safety properties and storage performance when compared to the pristine one for the pouch batteries • Li 3 BO 3 coating layer with Li-ion conductivity is applied to improve the LiNi 0.85 Co 0.05 Mn 0.10 O 2 . • Li 3 BO 3 layer serves as a remarkable scavenger of HF/F − to restrain the harmful HF/F − species. • Trace amount of B 3+ insertion could enhance the crystal structure stability of cathode. • Li 3 BO 3 coatedLiNi 0.85 Co 0.05 Mn 0.10 O 2 delivers the evident improvement on electrochemical properties and safety performance. • 2 wt% Li 3 BO 3 coated LiNi 0.85 Co 0.05 Mn 0.10 O 2 demonstrates the excellent electrochemical properties.