Electrochemical performances of Ni-rich and Li-rich blended cathodes for Li-ion batteries

Abstract

Herein, the effect of the blending ratio on the capacity, energy density, and cycling performance of Ni-rich (LiNi0.8Co0.1Mn0.1O2) (NCM) and Li-rich (Li7/6Mn1/2Ni1/6Co1/6O2) (LR) cathode materials was investigated. The optimally blended cathode exhibited capacity retentions of 80.7% and 76.9% after 200 cycles at 25 °C within 2–4.6 V and 100 cycles at 55 °C within 2–4.5 V, respectively, showing higher cycling stability and flatter voltage decline than pure NCM and pure LR cathodes. Additionally, the optimized cathode exhibited the smallest increase in charge-transfer resistance (Rct) and highest Li-ion diffusion coefficient (DLi+) among all tested samples after high-temperature cycling. This study highlights the unique electrochemical properties of blended cathode materials and demonstrates their high structural stability in Li-ion batteries (LIBs).