Geological Survey (USCS), 1.5 billion t of world land-based Mn reserves have been identified, which is far more than the land-based reserves of Co and Ni, which are approximately 7.6 and 95 million t, respectively. According to the latest data from the U.S. Moreover, compared with manganese, cobalt and nickel are not economical enough and have higher biotoxicity. Co or Ni-based layered cathode materials have theoretical capacities of over 270 mAh g −1 nonetheless, only < 70% of the Li ions can be reversibly inserted in/extracted from the canonical LiCoO 2 cathode material, and for Ni-rich electrodes, less than 80% Li can cycle reversibly even under laboratory conditions furthermore, once the electrodes are under deep delithiation, oxygen evolution and structure collapse occur, which could give rise to severe safety issues and hinder their extensive commercial application. Although Fe-based olivine LiFePO 4 and Mn-based spinel LiMn 2O 4 have been widely utilized as commercial cathode materials, these compounds suffer from low theoretical/practical specific capacities thus, they have been replaced in the literature in the pursuit of higher energy density. However, due to their lower energy density and/or reliance on constrained natural resources, they cannot meet the demands for both excellent performance and low-cost LIBs. Traditional cathode materials, such as LiFePO 4, LiMn 2O 4, LiCoO 2, and LiMO 2 (M = Ni, Co, etc.), have been pervasive in today’s society. At the cell level, LIBs mainly consist of cathodes, anodes, separators and electrolytes, and cathode materials account for approximately 50% of all the material costs due to the expensive lithium and transition metal (TM) elements and lower practical capacity delivered by cathode materials therefore, cathode materials play a significant role in increasing the comprehensive performance of practical batteries and obtain much more attention than the other materials. The rapid expansion of portable electronics, electric vehicles, and smart grid systems calls for more advanced LIB materials, which should not only have excellent performance but also cost less. Among the diverse energy storage devices, lithium-ion batteries (LIBs) are the most popular and extensively applied in daily life due to their high energy density, long cycle life, and other outstanding properties. Energy storage devices are the bridge between the other two aspects and promote the effective and controllable utilization of renewable energy without the constraints of space and time. The use of energy can be roughly divided into the following three aspects: conversion, storage and application. This review summarizes the effectively optimized approaches and offers a few new possible enhancement methods from the perspective of the electronic-coordination-crystal structure for building better FMCMs for next-generation lithium-ion batteries. Additionally, beyond FMCMs, a profound discussion of current controversial issues, such as oxygen redox reaction, voltage decay and voltage hysteresis in Li 2MnO 3-based cathode materials, is also presented. Herein, we systematically review the history of FMCMs, correctly describe their structures, evaluate the advantages and challenges, and discuss the resolution strategies and latest developments. Recently, with the fast growth of vehicle electrification and large-scale energy-storage grids, there has been an urgent demand to develop novel FMCMs again actually, new waves of research based on FMCMs are being created. Nevertheless, inevitable problems, such as Jahn-Teller distortion, manganese dissolution and phase transition, still frustrate researchers thus, progress in full manganese-based cathode materials (FMCMs) has been relatively slow and limited in recent decades. ![]() Lithium-manganese-oxides have been exploited as promising cathode materials for many years due to their environmental friendliness, resource abundance and low biotoxicity.
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