锂离子电池正极材料LiCoO_2中Li,Co的定量分析

Determination of lithium and cobalt in cathode material LiCoO_2 for lithium ion battery

探讨了锂离子电池的正极材料LiCoO2中Li,Co及Co2+的定量分析方法.用原子吸收分光光度法测定Li,Co比;Li,Co工作曲线回归方程分别为A＝0.108 45C-0.000 57,A＝0.021 79C-0.000 70,相关系数分别为0.999 94和0.999 93;Li,Co回收率为97%～104%.用络合滴定法测定了样品中Co总量;用氧化还原滴定法测定了Co3+含量.用络合滴定法测定高纯Co2O3中Co含量,得到相对误差为-0.37%,RSD＝0.25%.样品中Co2+的含量用样品中Co的总量减去Co3+的含量得到.

The methods for the determination of Li, Co and Co2+ in cathode material LiCoO2 of lithium ion battery were discussed. The molar ratio of lithium to cobalt was determined by atomic absorption spectrometry. The regression equations of Li and Co working curves were as follows: A = 0.10845C - 0.00057, A = 0.021 79C - 0.00070. The correlation coefficients were 0.999 94 for Li and 0.99993 for cobalt. The recoveries for lithium and cobalt were in the range of 97%~104%. The total amounts of Co in samples were determined by complexometry. In order to examine the accuracy of complexometry Co in high pure Co2O3 was determined. The relative error was -0.37% and RSD was 0.25%. The amounts of Co3+ in samples were determined by oxidation-reduction titrimetry, and then the amounts of Co2+ were obtained by subtracting the amounts of Co3+ from the total amounts of Co.