Machine-learning-revealed statistics of the particle-carbon/binder detachment in lithium-ion battery cathodes
Machine-learning-revealed statistics of the particle-carbon/binder detachment in lithium-ion battery cathodes
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DOI：
10.1038/s41467-020-16233-5
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发表时间：
2020-05-08
影响因子：
16.6
通讯作者：
Liu, Yijin
中科院分区：
文献类型：
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作者：
Jiang, Zhisen;Li, Jizhou;Liu, Yijin
复合电极的微观结构决定了锂离子电池中单个电池颗粒如何充电和放电。这是一个前沿的挑战，实验可视化，并随后了解电池颗粒与导电基质的演变（脱离）附着的电化学后果。在这里，我们通过多尺度实验方法、机器学习辅助统计分析和实验信息数学建模的独特组合来解决这个问题。我们的研究结果表明，颗粒的脱离程度与充电速率呈正相关，并且较小的颗粒在脱离碳/粘结剂基体时表现出更高的不确定性。我们进一步探讨了利用重构电子密度作为电荷状态代理的可行性和局限性。我们的研究结果强调了以统计可信度精确量化电池电极微观结构演变性质的重要性，这是最大限度地利用活性颗粒提高电池容量的关键。对富镍阴极中降解现象的理解正在深入研究中。在这里，作者使用学习辅助统计分析和实验知情的数学模型来解决富镍NMC复合阴极的微观结构。
The microstructure of a composite electrode determines how individual battery particles are charged and discharged in a lithium-ion battery. It is a frontier challenge to experimentally visualize and, subsequently, to understand the electrochemical consequences of battery particles' evolving (de)attachment with the conductive matrix. Herein, we tackle this issue with a unique combination of multiscale experimental approaches, machine-learning-assisted statistical analysis, and experiment-informed mathematical modeling. Our results suggest that the degree of particle detachment is positively correlated with the charging rate and that smaller particles exhibit a higher degree of uncertainty in their detachment from the carbon/binder matrix. We further explore the feasibility and limitation of utilizing the reconstructed electron density as a proxy for the state-of-charge. Our findings highlight the importance of precisely quantifying the evolving nature of the battery electrode's microstructure with statistical confidence, which is a key to maximize the utility of active particles towards higher battery capacity. Developing understanding of degradation phenomena in nickel rich cathodes is under intense investigation. Here the authors use learning-assisted statistical analysis and experiment-informed mathematical modelling to resolve the microstructure of a Ni-rich NMC composite cathode.