Optimizing the ratio of transition metal (TM) ions is an effective modification strategy to improve the electrochemical properties of LiNi_0.5+xCo_0.2+yMn_0.3+zO₂ (x+y+z=0, and the absolute values of x, y and z are not more than 0.03). In this work, we develope a new method which combines the simplex method with the normalization method of evaluation index (SNEI) to optimize the TM ion ratio of LiNi_0.5+xCo_0.2+yMn_0.3+zO₂. This method can significantly improve the optimization efficiency. Only after three times of simplex operation, the optimum component of LiNi_0.493Co_0.214Mn_0.293O₂ is obtained. The results show that the electrochemical properties of material have improved significantly through adjustment of the ratio of TM ions slightly, and LiNi_0.493Co_0.214Mn_0.293O₂-based cells exhibit long cycle life and good rate capability due to the low degree of Li/Ni mixing and the slow increase of impedance during cycling. Simultaneously, the impact of the intensity of the TM ion ratio on electrochemical performances are studied, and the following trend is observed in decreasing the sensitivity of the evaluation indexes: cycle performance > rate capacity > specific capacity. This newly-developed SNEI method has a wide applicability and great prospects in electrolyte and electrode formulations.

优化过渡金属离子比率是改善LiNi _{0.5 + x} Co _{0.2 + y} Mn _{0.3 + z} O ₂（x + y + z = 0，x的绝对值）的电化学性能的有效修饰策略，y和z不大于0.03）。在这项工作中，我们开发了一种新方法，该方法将单纯形法与评估指数的标准化方法（SNEI）相结合，以优化LiNi _{0.5 + x} Co _{0.2 + y} Mn _{0.3 + z} O ₂的TM离子比率。该方法可以显着提高优化效率。仅经过3次单工操作，LiNi _0.493 Co _0.214 Mn的最佳成分获得_0.293 O ₂。结果表明，通过略微调节TM离子的比例和LiNi _0.493 Co _0.214 Mn _0.293 O ₂可以显着改善材料的电化学性能。锂/镍混合程度低以及循环过程中阻抗缓慢增加，使得基于锂电池的电池具有长循环寿命和良好的倍率性能。同时，研究了TM离子比强度对电化学性能的影响，观察到降低评价指标敏感性的趋势如下：循环性能>倍率容量>比容量。这种新开发的SNEI方法在电解质和电极配方中具有广泛的适用性和广阔的前景。