电感耦合等离子体原子发射光谱-实时内标法测定锂电池三元正极材料中主量元素

锂电池正极材料中镍、钴、锰元素的物质的量占比对锂电池性能有较大影响,而使用电感耦合等离子体原子发射光谱法测定其物质的量占比时,存在数据波动大、稳定性差导致无法精确计算等问题。实验使用电感耦合等离子体原子发射光谱(ICP-AES),并采用实时内标法(Real-Time Internal Standardization,RTIS)测定锂电池三元正极材料中主量元素镍、钴、锰。通过实时内标法将样品中待测元素镍、钴、锰与内标元素钇在同一个时间测定从而消除进样系统噪音、等离子体稳定性等对结果产生的影响。按照实验方法测定4个锂电池三元正极材料中镍、钴、锰的物质的量占比,结果的相对标准偏差(RSD,n=3)不大于0.1%;各元素重复测定的绝对偏差绝对值为0.000 1%～0.022 3%;各元素2h连续测定的结果的相对标准偏差(RSD,n=8)为0.038%～0.099%。

Determination of major elements in ternary anode material forlithium battery by inductively coupled plasma atomic emissionspectrometry with real-time internal standardization

The molar ratio of Ni, Co and Mn in ternary anode material has a great influence on the performance of lithium battery. During the determination of molar ratio by inductively coupled plasma atomic emission spectrometry (ICP-AES), the accurate calculation is hardly conducted due to the large data fluctuation and poor stability. The major elements (i.e., Ni, Co and Mn) in ternary anode material for lithium battery were determined by ICP-AES with real-time internal standardization (RTIS). The testing elements (i.e., Ni, Co and Mn) in sample were determined at the same time with internal standard element (i.e., yttrium) by RTIS method, thus eliminating the influences of noise in sampling system and stability of plasma on the determination results. The molar percents of Ni, Co and Mn in four ternary anode material samples for lithium battery were determined according to the experimental method. The relative standard deviations (RSD, n=3) of determination results were less than 0.1%. The absolute values of deviation for determination of elements were between 0.0001% and 0.0223%. The RSDs (n=8) of determination results of elements within 2h were between 0.038% and 0.099%.