Collaborative modification based on Ti-ion effectively improves the electrochemical performance of Ni-rich LiNi0.8Co0.1Mn0.1O2 cathode materials

Through the wet coating method combined with high temperature calcining, samples based on Ti element coating and doping collaborative modification at different temperatures were obtained respectively (NCM811-Ti450, NCM811-Ti650, and NCM811-Ti850). Tests have shown that the TiO2 coating layer was successfully coated on the surface of the pure sample (NCM811). Additionally, with the increase of sintering temperature, Ti element in the part of the coating layer diffused into the crystal structure of LiNi0.8Co0.1Mn0.1O2 to form doping modification, which reduced the mixing degree of lithium nickel and expands the diffusion channel of lithium-ion. The electrochemical performance of co-modified samples displayed better cyclic stability and rate performance. Besides, the EIS test shows that the samples obtained from the collaborative modification have higher DLi+, which is improved from 9.14 × 10−16 cm2s−1 (NCM811) to 5.66 × 10−15 cm2s−1 (NCM811-Ti850).