Enhanced electrochemical performances of cerium-doped Li-Rich Li1.2Ni0.13Co0.13Mn0.54O2 cathode materials

Highlights: • Ce⁴⁺ with large ion radius expands the lattice and promote Li⁺ migration. • The cation disordering of Li⁺ and Ni²⁺ are depressed. • The introduced spinel phase enhances the structural stability. • The spinel phase provides 3D diffusion channels for fast Li⁺ migration. -- Abstract: The effects of cerium doping and the formation of layered-spinel hetero-structure on the electrochemical properties of lithium-rich cathode material were studied. The doped sample with layered-spinel phase exhibited enhanced cycling rate capability and long-term cyclability, which achieved an initial discharge capacity of 265.4 mAh g⁻¹ at 0.1 C and the capacity retention was 98.2% after 100 cycles at 1.0 C. The existence of layered-spinel hetero-structure in lithium-rich layered cathode material induced by cerium doping was believed to contribute to the remarkable improvement of cycling stability and rate capability. Cerium doping and the formation of spinel phase together facilitated lithium ion diffusion and inhibited the structural collapse during cycling.