快速测定废旧锂电池中的锂离子浓度

Determination of Lithium Ion Concentration in Scrapped Lithium-ion Batteries by Ultraviolet Spectrophotometry

锂离子电池的回收符合国家能源战略需求。在回收的过程中,需对Li^(+)的浓度进行测定,以便于锂的二次利用。采用紫外分光光度法对溶液中的Li^(+)浓度进行了测定,考察了锂配合物紫外吸收峰、反应时间、重现性等测定条件对Li^(+)的质量浓度测定的影响,得到了吸光度A与Li^(+)的浓度c的回归曲线:A=0.2935c+0.5361,r^(2)=0.9962,且重现性实验相对标准偏差(RSD)为0.9%(n=8),同时在3次无水LiCl的样品测定中标准差分别为0.0145%、0.2466%、0.2317%。这种方法测试准确,且避免了大型仪器的场地和操作要求,为Li^(+)的检测提供了更简捷快速的测定方法。

The recovery of lithium ion batteries meets the needs of the national energy strategy.During recovery,the concentration of Li^(+)is determined to facilitate secondary utilization of lithium.In this paper,the concentration of Li^(+)in solution was determined by ultraviolet spectrophotometry.The effects of determination conditions such as ultraviolet absorption peak of lithium complex,reaction time,and repeatability on the determination of Li^(+)content were investigated.The regression curve of absorbance A and concentration c of Li^(+)was obtained:A=0.2935c+0.5361,r^(2)=0.9962,and the relative standard deviation(RSD)was 0.9%.The test results were accurate,and the requirements of large-scale instruments for site operation were avoided.This method is simple and rapid,and can be used in the detection of Li^(+).