The development of high energy density LiNi_0.5Mn_1.5O₄ (LNMO) cathode materials for lithium-ion batteries are challenged by capacity degradation, which becomes more aggravated particularly at elevated temperatures. Thus, the practical strategy with facile craft and the viability of large-scale preparation for industrialized applications should be developed urgently. In this work, a micron-sized LNMO single crystals is synthesized by a facile two-step method consisting of an alcohol gel solvent method and a segmented sintering reaction. Results show that the truncated polyhedron LNMO-900 sample, with the moderate D₅₀ characteristic value of 4.429 μm and the highest tap density of 2.31 g cm⁻³, provides a stable structural and chemical stability even at elevated testing temperature due to its moderate specific surface area and the few Fd-3m phase. The LNMO/Li half-cells display more excellent capacity retention (87.3% at 1C and 25 °C after 500 cycles) and better thermal stability (76.65% at 1C and 55 °C after 200 cycles) than those of the single crystals of LNMO-850 and LNMO-950. Besides, the XPS, in-situ EIS and electrochemical tests results also prove that the LNMO-900 exhibits the lowest electrolyte decomposition degree, owing to a thin and effective solid-electrolyte interfacial film formed after cycles.

用于锂离子电池的高能量密度 LiNi _0.5 Mn _1.5 O ₄ (LNMO) 正极材料的开发面临着容量下降的挑战，尤其是在升高的温度下，容量下降变得更加严重。因此，迫切需要开发具有简便工艺和大规模制备工业化应用可行性的实用策略。在这项工作中，通过由醇凝胶溶剂法和分段烧结反应组成的简便的两步法合成了微米级 LNMO 单晶。结果表明，截断多面体LNMO-900样品具有中等的D ₅₀特征值4.429 μm和最高振实密度2.31 g cm ^-3, 由于其中等比表面积和少量 Fd-3m 相，即使在升高的测试温度下也能提供稳定的结构和化学稳定性。与 LNMO 单晶相比，LNMO/Li 半电池显示出更优异的容量保持率（500 次循环后在 1C 和 25°C 下为 87.3%）和更好的热稳定性（在 1C 和 55°C 下为 76.65%，200 次循环后） -850 和 LNMO-950。此外，XPS、原位 EIS 和电化学测试结果也证明 LNMO-900 表现出最低的电解质分解程度，这是由于循环后形成的薄而有效的固体电解质界面膜。