Investigation of Sn-Doped Lithium-Rich Layered Oxides Based on Self-Assembled Secondary Particles Composed of Exposed...

Lithium-rich layered oxides, known for their high initial capacity, have attracted significant attention; however, the irreversible loss of lattice oxygen leads to low initial Coulombic efficiency, poor rate performance, and voltage decay, severely restricting their practical application. Here, we propose a Sn-doped modification strategy based on secondary particles with abundant exposed (010) planes. The exposed (010) planes at the interface can accelerate Li⁺ insertion/extraction, which enhance the rate performance of lithium-rich layered oxides. Additionally, the incorporation of Sn doping effectively reduces the irreversible lattice oxygen loss to enhance the cycle stability of lithium-rich layered oxides. Integration of the benefits of both methods could significantly enhance the electrochemical performance. The results indicate that the sample doped with 1 mol % Sn achieves a capacity retention of 96% over 150 cycles at 0.2 C, demonstrating excellent rate performance as well. This work provides a valuable reference for the modification research of lithium-rich layered oxides.