Reviving the lithium-manganese-based layered oxide cathodes for lithium-ion batteries

Summary In the past several decades, the research communities have witnessed the explosive development of lithium-ion batteries, largely based on the diverse landmark cathode materials, among which the application of manganese has been intensively considered due to the economic rationale and impressive properties. Lithium-manganese-based layered oxides (LMLOs) are one of the most promising cathode material families based on an overall theoretical evaluation covering the energy density, cost, eco-friendship, etc. Unfortunately, the Mn3+ cation introduces severe Jahn–Teller (J–T) effect, which profoundly distorts the localized lattice structure and reduces the electrochemical stability. This perspective presents the principal comprehensions of the J–T effect in LMLOs and offers an outline picture of material design to suppress it. We outline the history of material design and further assess available approaches to address the J–T effect. Finally, we tentatively propose promising design trends with eliminated J–T effect to revive this important cathode material family toward practical applications.