Miele Ermanno, Dose Wesley M, Manyakin Ilya, Frosz Michael H, Ruff Zachary, De Volder Michael F L, Grey Clare P, Baumberg Jeremy J, Euser Tijmen G
Nanophotonics Centre, Department of Physics, Cavendish Laboratory, University of Cambridge, CB3 0HE, Cambridge, United Kingdom.
Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK.
Nat Commun. 2022 Mar 28;13(1):1651. doi: 10.1038/s41467-022-29330-4.
Improved analytical tools are urgently required to identify degradation and failure mechanisms in Li-ion batteries. However, understanding and ultimately avoiding these detrimental mechanisms requires continuous tracking of complex electrochemical processes in different battery components. Here, we report an operando spectroscopy method that enables monitoring the chemistry of a carbonate-based liquid electrolyte during electrochemical cycling in Li-ion batteries with a graphite anode and a LiNiMnCoO cathode. By embedding a hollow-core optical fibre probe inside a lab-scale pouch cell, we demonstrate the effective evolution of the liquid electrolyte species by background-free Raman spectroscopy. The analysis of the spectroscopy measurements reveals changes in the ratio of carbonate solvents and electrolyte additives as a function of the cell voltage and show the potential to track the lithium-ion solvation dynamics. The proposed operando methodology contributes to understanding better the current Li-ion battery limitations and paves the way for studies of the degradation mechanisms in different electrochemical energy storage systems.
迫切需要改进分析工具来识别锂离子电池中的降解和失效机制。然而，要理解并最终避免这些有害机制，需要持续跟踪不同电池组件中复杂的电化学过程。在此，我们报告了一种原位光谱方法，该方法能够在具有石墨阳极和LiNiMnCoO阴极的锂离子电池电化学循环过程中监测基于碳酸盐的液体电解质的化学性质。通过将空心光纤探头嵌入实验室规模的软包电池内部，我们利用无背景拉曼光谱证明了液体电解质物种的有效演变。光谱测量分析揭示了碳酸盐溶剂和电解质添加剂的比例随电池电压的变化，并显示了跟踪锂离子溶剂化动力学的潜力。所提出的原位方法有助于更好地理解当前锂离子电池的局限性，并为研究不同电化学储能系统中的降解机制铺平道路。
