Enhancing Rate Capacity and Cycle Stability of LiNi 1/3 Co 1/3 Mn 1/3 O 2 Cathode Material by Laminar V 2 O 5 Coating for Lithium‐Ion Batteries

Abstract The laminar V 2 O 5 ‐coated LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM‐V 2 O 5 ) was successfully synthesized via a facile wet‐coating method using NH 4 VO 3 as the modifier precursor. The phase structure, microscopic morphologies, and element distribution of a thin V 2 O 5 layer were investigated by a serials of ex‐situ characterization analysis. Subsequently, the phase changes of NCM‐V 2 O 5 during first charge/discharge were researched by ex‐situ (X‐ray diffraction) XRD tests, which reveals the prominent structural stability. NCM‐V 2 O 5 material shows an advanced rate performance due to elimination of surface lithium impurities, improvement of lithium‐ions diffusion, and impedance reduction. Additionally, excellent cycling performance mainly relies on the alleviated parasitic side reactions at the electrode and electrolyte interface. Specifically, the NCM‐V 2 O 5 retains 89.23 % capacity retention at 1 C after 100 cycles. What's more, NCM‐V 2 O 5 delivers 131.3 (5 C) and 123.1 mAh g −1 (10 C) capacity, and it achieves 88.65 % (5 C) and 88.22 % (10 C) capacity retention after 200 cycles. This work provides an effective guidance for the design of lithium‐ion battery cathode materials with high‐rate performance.