Comparison of Nanorod-Structured Li[Ni0.54Co0.16Mn0.30]O2 with Conventional Cathode Materials for Li-Ion Batteries

Abstract

We successfully synthesized a safe, high-capacity cathode material specifically engineered for EV applications with a full concentration gradient (FCG) of Ni and Co ions at a fixed Mn content throughout the particles. The electrochemical and thermal properties of the FCG Li[Ni0.54Co0.16Mn0.30]O-2 were evaluated and compared to those of conventional Li[Ni0.5Co0.2Mn0.3]O-2 and Li[Ni1/3Co1/3Mn1/3]O-2 materials. It was found that the FCG Li[Ni0.54Co0.16Mn0.30]O-2 demonstrated a higher discharge capacity and a superior lithium intercalation stability compared to Li[Ni0.5Co0.2Mn0.3]O-2 and Li[Ni1/3Co1/3Mn1/3]O-2 over all of the tested voltage ranges. The results of electrochemical impedance spectroscopy and transition-metal dissolution demonstrate that the microstructure of primary particle with rod-shaped morphology plays an important role in reducing metal dissolution, which thereby decreases the charge transfer resistance as a result of stabilization of the host structure.