Layered Cathode Materials for Lithium-Ion Batteries: Review of Computational Studies on LiNi_{1- x- y}Co_xMn_yO₂ and LiNi_{1- x- y}Co_xAl_yO₂

At present the most successful rechargeable battery is the Li-ion battery, due to the small size, high energy density, and low reduction potential of Li. Computational materials science has become an increasingly important tool to study these batteries, and in particular cathode properties. In silico studies of cathode materials have proven to be a valuable tool to understand the workings of cathodes, without having to do sophisticated experiments. First-principles and empirical computations have been used by various groups to study key properties, such as structural stability, electronic structure, ion diffusion mechanisms, equilibrium cell voltage, thermal and electrochemical stability, and surface behavior of Li-ion battery cathode materials. Arguably, the most practical and promising Li-ion cathode materials today are layered oxide materials, and in particular LiNi_1-x-yCo_xMn_yO₂ (NCM) and LiNi_1-x-yCo_xAl_yO₂ (NCA). Here, some of the computational approaches to studying Li-ion batteries, with special focus on issues related to layered materials, are discussed. Subsequently, an overview of theoretical and related experimental work performed on layered cathode materials, and in particular on NCM and NCA materials, is provided.