Alignment does matter: Design thick electrodes to improve the comprehensive lithium storage performance
Alignment does matter: Design thick electrodes to improve the comprehensive lithium storage performance
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DOI：
10.1016/j.carbon.2023.02.015
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发表时间：
2023-02
期刊：
影响因子：
10.9
通讯作者：
Bo Nie;Mingxin Li;Tiankai Yao;Haoqing Yang;L. Duan;Juchen Zhang;Guoqing Xin;Tengxiao Liu-;Hongtao Sun;Jie Lian
中科院分区：
文献类型：
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作者：
Bo Nie;Mingxin Li;Tiankai Yao;Haoqing Yang;L. Duan;Juchen Zhang;Guoqing Xin;Tengxiao Liu-;Hongtao Sun;Jie Lian
开发能够同时提供高面积、体积和重量性能的电化学能量存储是一项重大的基础和技术挑战。使电极更厚和更致密以获得高面积和体积性能，同时维持高水平的重量性能是简单的，但存在问题。在这些具有高质量负载和电极密度的电极中，不充分的电荷传输会严重降低能量存储性能。在此，我们开发了一种节能的快速烧结方法（例如，火花等离子体烧结）以制造具有高电极密度（2.0-2.3 g cm-3）和高质量负载（70-100 mg cm-2）的结构阴极。超厚电极（300-500 μm）中的垂直排列的碳网络和各向异性孔通道被设计和定制为在整个厚度上有效地传输电荷。结果，烧结的结构电极在正常电流（<2 mA cm-2）下表现出高面积（8.6mAh cm-2）、体积容量（246 mAh cm-3）、不妥协的重量性能（164 mAh g-1），以及在4.5mA cm-2的电流密度下200次循环后容量保持率为84%的稳定循环。
Developing electrochemical energy storage that enables simultaneously delivering high areal, volumetric, and gravimetric performance is a grand fundamental and technological challenge. It is straightforward but problematic to make electrodes thicker and denser for high areal and volumetric performance while sustaining a high level of gravimetric performance. The insufficient charge transports in these electrodes with high mass loading and electrode density could severely degrade the energy storage performance. Herein, we developed an energy-efficient fast sintering method (e.g., Spark Plasma Sintering) to fabricate a structural cathode with a high electrode density (2.0–2.3 g cm−3) and high mass loading (70–100 mg cm−2). The vertically aligned carbon networks and anisotropic pore channels in the ultrathick electrodes (300–500 μm) are designed and tailored for efficient charge transports throughout the whole thickness. As a result, the sintered structural electrodes perform high areal (8.6 mAh cm−2), volumetric capacity (246 mAh cm−3), uncompromised gravimetric performance (164 mAh g−1) at normal current (<2 mA cm−2), and stable cycling with a capacity retention of 84% after 200 cycles under a current density of 4.5 mA cm−2.