Ni‐rich Li‐ion cathode materials promise high energy density, but are limited in power density and cycle life, resulting from their poor dynamic characteristics and quick degradation. On the other hand, capacitor electrode materials promise high power density and long cycle life but limited capacities. A joint energy storage mechanism of these two kinds is performed in the material‐compositional level in this paper. A valence coupling between carbon π‐electrons and O²⁻ is identified in the as‐prepared composite material, using a tracking X‐ray photoelectron spectroscopy strategy. Besides delivering capacity simultaneously from its LiNi_0.8Co_0.1Mn_0.1O₂ and capacitive carbon components with impressive amount and speed, this material shows robust cycling stability by preventing oxygen emission and phase transformation via the discovered valence coupling effect. Structural evolution of the composite shows a more flattened path compared to that of the pure LiNi_0.8Co_0.1Mn_0.1O₂, revealed by the in situ X‐ray diffraction strategy. Without obvious phase transformation and losing active contents in this composite material, long cycling can be achieved.

中文翻译：

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脱嵌-嵌入阴极材料中的快速电容储能和长循环寿命

富镍的锂离子阴极材料具有很高的能量密度，但由于其动态特性差且降解迅速，因此功率密度和循环寿命受到限制。另一方面，电容器电极材料保证了高功率密度和长循环寿命，但是容量有限。本文在材料组成层面上执行了这两种联合能量存储机制。使用跟踪X射线光电子能谱策略，在制备的复合材料中确定了碳π电子与O ²⁻之间的价键耦合。除了从LiNi _0.8 Co _0.1 Mn _0.1 O ₂同时输送容量以及具有令人印象深刻的数量和速度的电容性碳组分，这种材料通过发现的价键耦合效应防止氧气释放和相变，从而显示出强大的循环稳定性。与纯LiNi _0.8 Co _0.1 Mn _0.1 O ₂相比，复合材料的结构演变显示出更平坦的路径，这是通过原位X射线衍射策略揭示的。没有明显的相变并且没有损失这种复合材料中的活性成分，就可以实现长循环。