Enhanced Electrochemical Properties of Zr(4+)-doped Li(1.20)[Mn(0.52)Ni(0.20)Co(0.08)]O(2) Cathode Material for Lithium-ion Battery at Elevated Temperature

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.