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 at. 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 exptl. 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 0.000 1%and 0.022 3%.The RSDs(n=8)of determination results of elements within 2 hwere between 0.038% and 0.099%.