Impact of Tantalum added to Ni-based positive electrode materials for Lithium-ion Batteries

Tantalum-containing, LiNiO2 was synthesized by first coating Ni(OH)2 precursor with nano-Ta2O5 by dry particle fusion. The coated precursor was then heated with LiOH & sdot;H2O to form the layered oxide. By analogy with our previous work on tungsten-containing LiNiO2, it is believed the Ta is present in the samples as a LixTayOz secondary phase which coats the grain boundaries of the primary particles within the secondary particles. The structural and electrochemical properties of the synthesized samples were studied by x-ray diffraction (XRD), extended x-ray absorption fine structure (EXAFS), scanning electron microscopy (SEM) and long term charge-discharge cycling tests. Among all the samples created, LiNiO2 containing 0.75 mol% Ta showed the best capacity retention of 94.4 % after 60 cycles between 4.3 and 3.0 V at 30 degrees C.

Automated summary

In this study, tantalum-containing LiNiO2 material was synthesized by coating and its structural and electrochemical properties were investigated. The experimental results showed that LiNiO2 containing 0.75 mol% Ta exhibited the best capacity retention among all the synthesized samples.