Synthesis and electrochemical properties of Er3+ Doped Li[Li0.2Mn0.54Ni0.13 Co0.13]O2 as cathode materials for lithium ion bateries

Abstract

Li1.20[Mn0.54Ni0.13Co0.13]0.80-xErxO2 (x = 0, 0.01, 0.02, 0.03) cathode materials were synthesized using a combination of co-precipitation and high-temperature sintering. XRD, SEM, and TEM analyses and galvanostatic charge-discharge tests were carried out to study the influences of Er3+ doping on the crystal structural, morphology and electrochemical properties of Li1.20Mn0.54Ni0.13Co0.13O2. The XRD results revealed that Er3+ doping decreased the cation mixing degree. The galvanostatic charge-discharge test results showed that improved electrochemical properties were obtained through Er3+ doping. With an increasing Er3+ doping content, the capacity retentions were enhanced from 88.1% to 92.8% and then decreased to 90.2% after 100 cycles with x = 0.01, 0.02 and 0.03, respectively, while the undoped sample delivered a capacity retention of 84.6%. In addition, the discharge capacity of Li1.20[Mn0.52Ni0.13Co0.13Er0.02]O2 was approximately 23.0 mAh g-1 larger than that of the undoped sample at a high rate of 5 C.