Spherically Smooth Cathode Particles by Mechanofusion Processing

Surface modification has been shown to be useful for improving the cycling performance of cathode materials. Typically hetero-compositional coatings are applied on cathode particle surfaces using methods, such as aqueous deposition and atomic layer deposition (ALD), that can be expensive and inefficient. In this report, a dry mechanofusion method was used to treat cathode particles with no auxiliary coating applied. This resulted in a drastic reduction in surface area and the elimination of surface features on the particles. Furthermore, the processing results in an iso-compositional amorphous shell on the surface of each particle. The resulting particles have improved cycling. We believe the mechanofusion process is an important step toward the goal of improving the cycling performance of cathode materials.