Influence of Boron Substitution on the Crystal and Electronic Properties of LiCrO2 Battery Cathode

Boron-substituted LiCrO 2 battery cathode material samples were investigated by X-ray-based techniques to probe the influence of boron on their crystal and electronic structure properties. Studies were carried on a series of Li-ion battery cathode materials with the general formula LiCr 1− x B x O 2 . Up to 10 pct boron substitution amounts, light boron atoms were determined to sit in Cr coordinations. However, for more substitutions (>10 pct), higher electronegativity of boron was determined to govern the crystal structure by obtaining isolated boron-centered domains and built Li 2 BO 4 structures. Electronic structure studies and further crystal structure analysis were carried by X-ray absorption fine structure technique. In the studied samples, increasing boron concentration in the samples ( i.e. , >10 pct substitution) were determined to cause a decrease in oxygen bond distances as a result of boron sitting in some chromium locations. As a result of this study, 10 pct boron substitution was determined as a threshold to protect the LiCrO 2 crystal structure.