Facile Morphology Modulation to Enhance Stability and Fast Kinetics of Anionic Redox for Li-Rich Layered Oxides Cathodes

Abstract

Li-rich layered oxide cathodes (LLOs) have been regarded as promising high-energy-density cathode materials for lithium-ion batteries due to exceptional specific capacity and eco-friendly nature. However, issues such as irreversible oxygen evolution and severe structural degradation have led to low initial Coulombic efficiency (ICE), poor cycling stability, voltage decay, and unfavorable rate performance. In this work, we have systematically manipulated the morphologies and structures of low cobalt-containing LLOs, specifically Li 1.08 Mn 0.54 Ni 0.21 Co 0.07 O 2 , to stabilize anionic redox chemistry and enhance the rapid kinetic performance of LLOs, resulting in optimized electrochemical properties. Electrochemical testing has demonstrated that LLOs with radial shapes exhibit superior performance, achieving a high ICE of 88.74% with reversible discharging capacity of 285.1 mAh/g and excellent capacity retention of 85.35% at 1 C after 100 cycles. Furthermore, even at 5 C, these LLOs maintain a high discharge capacity of 165.8 mAh/g, indicating significantly improved rate performance due to modulation of their morphology and structure. This work provides valuable insight into the design of high-energy-density LLOs via morphology and structure modulation, laying the groundwork for large-scale production of lithium-ion batteries in the near future.