Effect of Ball Milling on the Atomic Configuration of Li_1.3Nb_0.3Fe_0.4O₂ with a Disordered Rocksalt Structure

Abstract

In this paper, we focused on Li_1.3Nb_0.3Fe_0.4O₂ with a disordered rocksalt structure as positive-electrode materials for lithium-ion batteries, and investigated an effect of ball milling on the atomic configuration. X-ray absorption fine structure measurements and neutron and X-ray total scattering measurements were performed on an as-synthesized sample (a pristine sample) and a ball-milled sample, and it is revealed that the ball milling disrupts the atomic configuration significantly. In addition, reverse Monte Carlo modeling using the total scattering data was conducted for both the samples, and the obtained three-dimensional atomic configurations were used to visualize the space available for Li⁺ diffusion in charging and discharging processes. The results indicate that the ball milling distorts the Li⁺ diffusion path and causes fragmentation of the path, leading to a deterioration in electrode performance.