Single Crystal Layered Oxide Cathodes: The Relationship between Particle Size, Rate Capability, and Stability

With the increasing demand for safer, more stable, and energy dense batteries, investigations into single crystal layered oxide cathodes have gained momentum. However, translating considerations from polycrystalline to single‐crystalline particles and their ensembles is not one‐to‐one. Lithium diffusion path length, surface, dopants and coatings, as well as the synthetic methods used take on different dimensions for single‐crystalline particles. In this concept article, we review key considerations that must be made when developing well‐performing single crystal layered oxide cathodes. We discuss how diffusion limitations can affect material stability in addition to how improvements to diffusivity can act as a method to simultaneously improve rate capability and surface stability. In addition, we briefly discuss how the unique feature of faceting and the synthetic design space for single‐crystalline particles should be conceptualized.