Enhancement of the electrochemical properties of the nickel-rich cathode material LiNi0.815Co0.15Al0.035O2 by WO3 coating

LiNi 0.815 Co 0.15 Al 0.035 O 2 (NCA) has attracted a lot of attention owing to its high specific capacity and low cost. The problems of capacity loss and interface side reaction during the long cycle hinder the application of NCA cathode materials. In this work, WO 3 -coated LiNi 0.815 Co 0.15 Al 0.035 O 2 cathode materials were successfully prepared, which greatly improved the electrochemical properties of the NCA. Results of XRD show that the WO 3 coating has no significant effect on the structure of the NCA samples. Results of XPS show that WO 3 coating is beneficial to reduce the content of residual alkali substance on the surface of the NCA. In addition, the first discharge specific capacity of NCA@2wt%WO 3 is 174.96 mAh g  − 1 at a current density of 1.0 C, with a capacity retention rate of 89.94% after 200 cycles. The discharge specific capacity of NCA@2wt%WO 3 is 137.74 mAh g  − 1 at 5.0 C. The coating of WO 3 effectively improves the electrochemical performance of NCA cathode materials.