Recently, energy storage devices with a high energy density have been demanded for the development of electric vehicles (EVs). Lithium-ion batteries (LIBs) are one of promising candidates, but the current energy density of LIBs is not enough to satisfy the requirements of EVs. Therefore, new cathode materials having high reversible capacities or high redox potentials should be suggested to increase the energy density of LIBs. One of promising high capacity cathode materials is Li-rich layered oxide materials (Li2MnO3·LiMO2, M=Ni, Co, Mn, and their combinations). They can deliver the reversible capacity of 200-250 mA h g~(-1), which is higher than the reversible capacity of commercialized LiNi1-x-yCoxMnyO2 (160-180 mA h g~(-1)). However, they also have challenging problems such as i) poor rate performance, ii) irreversible electrolyte decomposition, iii) voltage fading on cycling, and iv) oxygen gas evolution. Many research groups have studied the failure mechanisms of those materials through various ex situ or in situ analysis using TEM and DEMS, and suggested promising strategies such as surface modification showing the improved electrochemical performance. In this presentation, we report the voltage fading mechanism of the Li-rich layered oxide materials, particularly focusing on the comparison with the diffusion kinetics of Li ~+ ions in Li2MnO3 and LiMO2 crystallites of the integrated composite structure.
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机译：最近，已经要求具有高能量密度的能量存储装置来开发电动车辆（EVS）。锂离子电池（LIBS）是承诺的候选人之一，但是LIBS的当前能量密度不足以满足EVS的要求。因此，应建议具有高可逆容量或高氧化还原潜力的新型阴极材料来增加Libs的能量密度。承诺高容量的阴极材料之一是富富锂的层状氧化物材料（Li2MNO3·Limo2，M = Ni，Co，Mn及其组合）。它们可以提供200-250 mA H G〜（-1）的可逆容量，高于商业化LINI1-X-YCOXMNYO2的可逆容量（160-180 mA H g〜（-1））。然而，它们还具有挑战性问题，例如i）率低的速率性能，ii）不可逆电解质分解，III）循环越浅的循环，IV）氧气进化。许多研究组通过各种原地或使用TEM和DEM的原位分析研究了这些材料的失效机制，并提出了有前途的策略，如表面改性，呈现出改善的电化学性能。在该介绍中，我们报告了富富含量的层状氧化物材料的电压衰落机理，特别是与Li 2 MnO 3中Li〜+离子的扩散动力学的比较和集成复合结构的Li 2和Limo2微晶的比较。
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