Cobalt-free cathode material LiNi0.9Mn0.05Mg0.05O2 with high cycle stability synthesized via the homogeneous co-precipitation method†

Abstract

Lithium-ion batteries (LIBs) possess advantages such as high energy density and excellent cycle performance, making them widely utilized in various energy storage devices. However, common cathode materials often contain Co, which is both scarce and expensive. Consequently, the research and development of cobalt-free LIBs has become increasingly significant. In this study, the cathode material LiNi_0.9Mn_0.05Mg_0.05O₂ (NMM955) was synthesized using a homogeneous co-precipitation method, and its electrochemical properties were investigated through structural characterization and electrochemical testing. The results showed that NMM955 exhibited high electrochemical performance when the calcination temperature was 750 °C and the calcination time was 20 h. At 0.1C, the initial specific discharge capacity was 189.54 mA h g⁻¹, and the capacity retention rate after 50 cycles was 98.21%. At 1C, the initial specific discharge capacity was 150.32 mA h g⁻¹, and the capacity retention rate after 100 cycles was 97.01%, demonstrating that NMM955 offered a feasible strategy for developing highly stable, cobalt-free ternary cathode materials.