Cathode material Li(Ni_0.5Co_0.25Mn_0.25)_1-xZr_xO₂ (x = 0, 0.005, 0.01, 0.02, 0.03) and Li(Ni_0.5Co_0.25-yMn_0.25Al_y)_0.99Zr_0.01O₂ (y = 0, 0.01, 0.02, 0.03) were synthesized by coprecipitation method. The structure and electrochemical properties of cathode materials were mainly studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), charge/discharge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results of XRD show that Zr doping and Al-Zr co-doping cannot destroy the crystal structure, and they are all beneficial to structural stability. Electrochemical results show that the appropriate amount of Zr⁴⁺ doping can improve the rate and cycle performance. However, there is no further increase in the rate performance and cycle stability when Co is replaced with Al. Because of the 3a site occupation of the doped ions, it is possible that the diffusion of lithium ions is hindered. And Al is low electrochemically inert. In particular, x = 0.01 exhibited the best rate performance and cycle stability in all samples. The specific discharge capacity of the material is 151.0 mAh/g at 1C, and it still up to 173.3 mAh/g at 0.1C after experiencing high-rate discharge. And the capacity retention rate is 87.53% at 0.1C after 45 cycles. When Al³⁺ and Zr⁴⁺ are co-doped, the performance of y = 0.01 material is the best. The specific discharge capacity at 0.1C, 0.2C, 0.5C, 1C and 0.1C are 182, 148.3, 123.5, 110.3 and 125.8 mAh/g, respectively.

正极材料Li（Ni _0.5 Co _0.25 Mn _0.25）_1-x Zr _x O ₂（x = 0，0.005，0.01，0.02，0.03）和Li（Ni _0.5 Co _0.25-y Mn _0.25 Al _y）_0.99 Zr _0.01 O ₂通过共沉淀法合成了（y ＝ 0、0.01、0.02、0.03）。主要通过X射线衍射（XRD），扫描电子显微镜（SEM），能量色散谱仪（EDS），充放电测试，循环伏安法（CV）和电化学阻抗谱（EIS）研究正极材料的结构和电化学性能）。XRD的结果表明，Zr掺杂和Al-Zr共掺杂不会破坏晶体结构，都有利于结构稳定性。电化学结果表明适量的Zr ⁴⁺掺杂可以提高速率和循环性能。然而，当用Al代替Co时，速率性能和循环稳定性没有进一步提高。由于掺杂离子的3a位置占据，锂离子的扩散可能会受到阻碍。并且Al是低电化学惰性的。特别地，在所有样品中，x = 0.01表现出最佳的速率性能和循环稳定性。该材料在1C时的比放电容量为151.0 mAh / g，在经历高速率放电后在0.1C时仍高达173.3 mAh / g。45个循环后，在0.1C时容量保持率为87.53％。当Al ³⁺和Zr ⁴⁺在共掺杂时，y = 0.01材料的性能最佳。在0.1C，0.2C，0.5C，1C和0.1C时的比放电容量分别为182、148.3、123.5、110.3和125.8 mAh / g。