For polycrystalline lithium-rich manganese-based layered oxides (LMLO), the presence of porous microstructures always leads to the greater oxygen release and lower conductivity, impairing their rate and cycling stability performance for real applications. Here, by temperature-controlled annealing, we propose a facile and scalable method to infuse molten SeO₂ into the intracrystalline grain boundary of the polycrystalline Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ (LMNCO) particles. Then the uniform surface and double nanolayer structure composed of interconnected Li₂SeO₄ and robust Li₂Ni_xCo_yO₄ are revealed on primary particles. Accordingly, SeO₂-infused LMNCO(Se-LMNCO) gains an upraised rate performance with 97 % capacity retenting rate after charge and discharge under 0.1–5 C then returned to 0.1 C and an improved cycling stability with a capacity retention of 80.0 % over 200 cycles at 1 C (1 C=250 mAh g⁻¹). Our work highlights the significance of surface engineering inside the secondary LMLO particles and the improvement of electrochemical rate and stability performance toward lithium-ion batteries with LMLO electrode.

对于多晶富锂锰基层状氧化物（LMLO），多孔微结构的存在总是导致更多的氧气释放和更低的电导率，从而削弱它们在实际应用中的倍率和循环稳定性能。在这里，通过温控退火，我们提出了一种简便且可扩展的方法，将熔融的 SeO _{2注入多晶 Li 1.2} Mn _0.54 Ni _0.13 Co _0.13 O ₂ (LMNCO) 颗粒的晶内晶界然后由互连的 Li ₂ SeO ₄和坚固的 Li ₂ Ni _{x组成的均匀表面和双纳米层结构}Co _y O ₄显示在初级粒子上。因此，注入 SeO ₂的 LMNCO（Se-LMNCO）在 0.1-5 C 下充放电后容量保持率为 97%，然后恢复到 0.1 C，循环稳定性得到提高，容量保持率为 80.0%。 1 C (1 C=250 mAh g ^-1 ) 下 200 个循环。我们的工作强调了二次 LMLO 颗粒内部表面工程的重要性，以及使用 LMLO 电极提高锂离子电池的电化学速率和稳定性能。