摘要
锂/镍阳离子混排、表面副反应等问题限制高镍系三元正极材料的发展和应用。表面包覆是一种有效改善电化学性能的一种方法,首先通过共沉淀技术合成Ni0.8Co0.15Al0.05(OH)2前驱体,然后在其表面成功包覆一层LiZr2(PO4)3,最后在氧气气氛下烧结得到最终产物。采用FESEM、XRD等手段分析样品物相成分和组成,发现包覆前后样品都具有典型的α-NaFeO2层状结构。对材料进行循环性能测试,在2.8~4.3 V电压窗口下0.2 C活化3次,然后0.5 C电流密度下循环,发现改性后样品的循环稳定性得到明显提升,0.5 C循环400圈后容量保持率由原来的46.88%提升到58.76%。
Li+/Ni2+ cation mixed and surface side reactions have limited the development and application of Ni-rich ternary cathode materials. Surface coating is an effective method to improve electrochemical performance. We first synthesized the Ni0.8Co0.15Al0.05(OH)2 precursor by co-precipitation technology, and then successfully coated a layer of LiZr2(PO4)3 on the surface. Then we used FESEM, XRD and other methods to analyze the phase composition, found that the samples had a typical α-NaFeO2 layered structure. The material was tested for cycling performance. It was activated 3 times at 0.2 C under a voltage window of 2.8~4.3 V, and then circulated at a current density of 0.5 C. It was found that the cycling stability of the modified sample was significantly improved, and after 400 cycles at 0.5 C, the capacity retention increased from 46.88% to58.76%.
作者
张秋歌
丁举宣
杜一博
ZHANG Qiu-ge;DING Ju-xuan;DU Yi-bo(School of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei 230009,China)
出处
《安徽化工》
CAS
2020年第3期51-54,59,共5页
Anhui Chemical Industry
