Enhanced Electrochemical Properties of Zr4+-doped Li1.20[Mn0.52Ni0.20Co0.08]O2 Cathode Material for Lithium-ion Battery at Elevated Temperature

Abstract The typical co-precipitation method was adopted to synthesized the Li-excess Li 1.20 [Mn 0.52− x Zr x Ni 0.20 Co 0.08 ]O 2 ( x = 0, 0.01, 0.02, 0.03) series cathode materials. The influences of Zr 4+ doping modification on the microstructure and micromorphology of Li 1.20 [Mn 0.52 Ni 0.20 Co 0.08 ]O 2 cathode materials were studied intensively by the combinations of XRD, SEM, LPS and XPS. Besides, after the doping modification with zirconium ions, Li 1.20 [Mn 0.52 Ni 0.20 Co 0.08 ]O 2 cathode demonstrated the lower cation mixing, superior cycling performance and higher rate capacities. Among the four cathode materials, the Li 1.20 [Mn 0.50 Zr 0.02 Ni 0.20 Co 0.08 ]O 2 exhibited the prime electrochemical properties with a capacity retention of 88.7% (201.0 mAh g −1 ) after 100 cycles at 45 °C and a discharge capacity of 114.7 mAh g −1 at 2 C rate. The EIS results showed that the Zr 4+ doping modification can relieve the thickening of SEI films on the surface of cathode and accelerate the Li + diffusion rate during the charge and discharge process.