以丙烯酸热聚合法合成了富锂相正极材料Li[Li_0.2Mn_0.54Ni_0.13Co_0.13]O₂,并分别以Al³⁺取代Ni、Co、Mn元素进行掺杂改性。利用X射线衍射(XRD)和扫描电子显微镜(SEM)系统表征了材料的结构与形貌特征,通过组装扣式电池评估其比容量、倍率性能、循环稳定性和阻抗等电化学性能,对比研究了Al³⁺在不同晶体学位点掺杂对电化学性能的影响。结果表明:Al³⁺取代Ni位点时可以有效提高材料的倍率性能,而Co和Mn点位掺杂可以改善材料循环性能,显著抑制电压降现象。

The lithium-rich layered cathode material Li[Li_0.2Mn_0.54Ni_0.13Co_0.13]O₂ was synthesized via an acrylic acid thermal polymerization method.Al³⁺ doping modification was subsequently implemented by substituting Ni,Co,and Mn with Al³⁺.The structural and morphological characteristics of the prepared materials were systematically characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM).Coin-type cells were assembled to evaluate their electrochemical performance,including specific capacity,rate capability,cycling stability,and impedance.Furthermore,the influence of Al³⁺ doping at different crystallographic sites on the electrochemical properties was investigated.The experimental results showed that the substitution of Ni sites with Al³⁺ could effectively improve the rate performance of the material,while Co and Mn site doping could enhance the cycling performance of the material and significantly suppress the voltage decay.