将通过共沉淀法制备的M(OH)2(M= Mn, Ni)前驱体与ZnO和Li2CO3混合,合成了不同Zn2+掺杂量的Li1.13 Ni0.3-x Mn0.57 Znx O2材料. X射线衍射结果表明, Zn2+掺杂提升了材料的层状属性,降低了Li+/Ni2+混排程度.在2.0~4.8 V电压范围内, Zn2+掺杂材料表现出更高的可逆比容量,并具有良好的倍率性能和循环稳定性.示差扫描量热测试结果显示, Zn2+掺杂材料的热安全性能明显优于未掺杂材料.在所合成的材料中, Li1.13Ni0.29Mn0.57Zn0.01O2(Zn2+掺杂量x=0.01)具有最高的放电容量、最好的倍率性能和循环稳定性及极佳的热安全性能.%Zn-doped Li1. 13 Ni0. 3-x Mn0. 57 Znx O2 samples were synthesized by co-precipitation method. X-ray diffraction shows that Zn doping decreases the Li+/Ni2+ cation mixing of the material, increases the structure stability and expands the lattice volume of the material which provides more space for lithium ion intercalation/de-intercalation. Electrochemical experiments show that Zn doping decreases the charge transfer resistance of the electrode, improves the reversibility of lithium intercalation and de-intercalation, thus the electrochemical properties of the material are improved. Especially, the Li1. 13 Ni0. 29 Mn0. 57 Zn0. 01 O2 material with Zn doping of x=0. 01 shows the best electrochemical performance with the largest discharge capacity, best rate capability, excellent capacity retention and thermal stability.
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