In order to improve the normal temperature and high temperature cycling performance of spinel LiMn₂O₄, Mg²⁺-doped LiMn_2-xMg_xO₄(0 ≤ x ≤ 0.1) cathode material was synthesized by the liquid phase method. XRD and EDS tests show that the doped Mg²⁺ successfully replaced part of Mn³⁺ into the lithium manganate cathode material lattice. After doping, the crystal structure is a spinel structure without impurity phase. Electrochemical performance tests show that different Mg²⁺ doping amount can effectively inhibit LiMn₂O₄ capacity attenuation during charging and discharging. The specific capacity of LiMn_1.95Mg_0.05O₄ is 111.9 mAh/g at the current density of 0.2C at room temperature for the first discharge, the first discharge specific capacity of 1C was 110.06 mAh/g, and the discharge specific capacity was 105.79 mAh/g after 100 cycles, and the capacity retention rate is 96.12%. The specific capacity of the first discharge at a 0.2C current density at high temperature was 113.4 mAh/g, and after 100 cycles at 1C current density, the specific capacity is 99.29 mAh/g, and the capacity retention rate is 89.32%. The normal temperature and high temperature cycle performance of the sample is higher than that of the undoped Mg²⁺ sample.

为了提高尖晶石LiMn ₂ O ₄ 、Mg ²⁺ 掺杂LiMn _2-x Mg的常温和高温循环性能采用液相法合成了 _x O ₄ （0≤x≤0.1）正极材料。 XRD和EDS测试表明，掺杂的Mg ²⁺ 成功取代了部分Mn ³⁺ 进入锰酸锂正极材料晶格中。掺杂后晶体结构为尖晶石结构，无杂质相。电化学性能测试表明，不同Mg ²⁺ 掺杂量均能有效抑制LiMn ₂ O ₄ 充放电过程中的容量衰减。 LiMn _1.95 Mg _0.05 O ₄ 室温下首次放电电流密度0.2C时比容量为111.9 mAh/g，第一次放电1C放电比容量为110.06mAh/g，100次循环后放电比容量为105.79mAh/g，容量保持率为96.12%。高温下0.2C电流密度下首次放电比容量为113.4mAh/g，1C电流密度下循环100次后比容量为99.29mAh/g，容量保持率为89.32%。样品的常温和高温循环性能均高于未掺杂的Mg ²⁺ 样品。