Nano SIMS characterization of boron- and aluminum-coated LiNi1/3Co1/3Mn1/3O2 cathode materials for lithium secondary ion batteries

The LiNi_1/3Co_1/3Mn_1/3O₂ powders required for the present study, obtained by coprecipitation method has been surface coated with boron and aluminum. The morphology and crystal structure of powders have been characterized using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy techniques. The elemental distribution of the coated samples analyzed by transmission electron microscopy images and nano secondary ion mass spectrometry indicates a thin uniform layer of B, Al]₂O₃ on the surface of spherical LiNi_1/3Co_1/3Mn_1/3O₂. The surface-modified LiNi_1/3Co_1/3Mn_1/3O₂ has been explored as a cathode material for lithium secondary ion battery applications. The electrochemical charge–discharge results reveal that the capacity retention rate of coated LiNi_1/3Co_1/3Mn_1/3O₂ after 40 cycles at 1 C rate maintains 93% of the initial discharge capacity while the rate of bare LiNi_1/3Co_1/3Mn_1/3O₂ maintains only 88%. It is noticed that the small amounts of boron and aluminum coatings on the surface of LiNi_1/3Co_1/3Mn_1/3O₂ can significantly improve the electrochemical properties of electrode materials because of the suppression of reaction between the cathode and the electrolytes.