失效钴酸锂电极材料微结构修复研究

Study on microstructure repair of failure LiCoO_2 electrode materials

提出了针对失效钴酸锂(LiCoO_2)电极材料微结构修复的新工艺。将钴酸锂与硫酸氢钠(NaHSO_4·H_2O)分别按物质的量比为1∶0.05、1∶0.10混合,然后进行焙烧—溶解—修复。采用热重-差式扫描量热分析(TG-DSC)、电感耦合等离子体原子发射光谱仪(ICP-OES)、X射线衍射仪(XRD)、扫描电镜(SEM)等表征方法,研究了修复过程中材料的热量和质量的变化、成分的变化、相组成及晶胞参数的变化以及材料表面形貌的变化。研究结果表明,钴酸锂与硫酸氢钠混合在酸性环境焙烧的过程中其表面微结构发生了明显变化。以钴酸锂与硫酸氢钠物质的量比为1∶0.05的混合物经焙烧—溶解—修复所得钴酸锂,其晶格参数a=0.281 90 nm、c=1.390 41 nm、c/a=4.932 3,十分接近商用钴酸锂的晶格参数值。再生修复的钴酸锂材料颗粒粒径小,形状不规则。

A new technique for repairing the microstructure LiCoO2 electrode materials was proposed,and the mixtures of LiCoO2 and NaHSO4·H2O with the amount of substance ratio of 1 ：0.05 and 1 ：0.1,respectively,were roasted,dissolved,and repaired.The changes of heat,mass,phase composition,unit cell parameters,and the surface morphology were characterized by TG-DSC,ICP-OES,XRD,and SEM.Results indicated that the surface microstructure of the mixtures of LiCoO2 and NaHSO4＊H2O significantly changed during the calcination in acid environment.The LiCoO2 lattice constants repaired 10.05 mixtures of LiCoO2 and NaHSO4＊H2O approached to a=0.281 90 nm,c=1.390 41 nm,and c/ a=4.932 3 ,which were very close to the value of commercial LiCoO2. Besides,the morphologies of regeneration LiCoO2 were irregular and had a small particle size.