论文标题
关于LinixCoymnx阴极材料的可逆反应和不可逆反应的微观起源：Ni-O杂交键形成与阳离子和阴离子氧化还原
On the microscopic origin of reversible and irreversible reactions of LiNixCoyMnx cathode materials: Ni-O hybrid bond formation vs. cationic and anionic redox
论文作者
论文摘要
使用高级光谱和最先进的衍射。首次提供了明确的实验证据，即NCM中的氧化还原反应是通过Ni的可逆氧化和与O的杂交进行的，而不是通过纯阳离子或最近讨论的，纯净的阴离子氧化还原过程进行的，而不是广泛假设的。一旦形成了NI-O杂种状态，就无法进一步氧化位点。取而代之的是，不可逆转的反应设定导致结构崩溃，因此，缺乏离子NI限制了可逆能力。此外，随着NI含量而变化的杂交程度会触发阴极的电子结构和操作电位。随着NI量增加，材料的共价特征增加，电势减少。
Energy density limitations of layered oxides with different Ni contents, i.e., of the conventional cathode materials in Li-ion batteries, are investigated across the first discharge cycle using advanced spectroscopy and state-of-the-art diffraction. For the first time unambiguous experimental evidence is provided, that redox reactions in NCMs proceed via a reversible oxidation of Ni and a hybridization with O, and not, as widely assumed, via pure cationic or more recently discussed, pure anionic redox processes. Once Ni-O hybrid states are formed, the sites cannot be further oxidized. Instead, irreversible reactions set in which lead to a structural collapse and thus, the lack of ionic Ni limits the reversible capacity. Moreover, the degree of hybridization, which varies with the Ni content, triggers the electronic structure and the operation potential of the cathodes. With an increasing amount of Ni, the covalent character of the materials increases and the potential decreases.
