Synthesis Route Effect on the Electrochemical Performance of LiNi_0.6Mn_0.2Co_0.2O₂ Cathode Materials for Lithium Ion Battery

The effect of synthesis routes on the electrochemistry of Ni-rich LiNi_0.6Mn_0.2Co_0.2O₂ (NMC622) cathodes was investigated. The Ni-rich NMC622 cathode materials synthesized via two synthesis routes, namely solution combustion (Com) and sol-gel (Sol), were compared based on their electrochemical performance. X-ray diffraction (XRD), scanning electron microscopes (SEM), HR-TEM, and battery testing were used to examine the structural and electrochemical properties of the samples. Both the cycling stability and rate capability testing confirmed that the NMC622 cathode samples prepared by the combustion synthesis route exhibited better electrochemical performance than those synthesized by the Sol-gel method. The NMC622-Com sample delivered a first capacity of 184 mAh g⁻¹ and retained 117 mAh g⁻¹ after 100 cycles. NMC622-Sol, however, delivered a first capacity of only 144 mAh g⁻¹ and retained 103 mAh g⁻¹ after 100 cycles with better capacity retention than NMC622-Com. The higher capacity of NMC622-Com may be due to the smaller nanoparticles synthesized by the combustion route, resulting in more contact with the electrolyte.