Tao Runming, Tan Susheng, Meyer Iii Harry M, Sun Xiao-Guang, Steinhoff Bryan, Sardo Kahla, Bishtawi Amer, Gibbs Tillman, Li Jianlin
Electrification and Energy Infrastructures Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Department of Electrical and Computer Engineering, and the Gertrude E. and John M. Petersen Institute of NanoScience and Engineering, the University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States.
ACS Appl Mater Interfaces. 2023 Aug 30;15(34):40488-40495. doi: 10.1021/acsami.3c07225. Epub 2023 Aug 18.
Dry processing is a promising method for high-performance and low-cost lithium-ion battery manufacturing which uses polytetrafluoroethylene (PTFE) as a binder. However, the electrochemical stability of the PTFE binder in the cathodes and the generated chemistry of the cathode electrolyte interphase (CEI) layers are rarely reported. Herein, the CEI properties and PTFE electrochemical stability are studied via cycling the high-loading dry-processed electrodes in electrolytes with LiPF or LiClO salt. Using LiClO salt can eliminate other possible F sources, allowing the decomposition of PTFE to be studied. The detection of LiF in cells with the LiClO salt confirms that PTFE undergoes side reaction(s) in the cathodes. When compared with LiClO, the CEI layer is much thicker when LiPF is used as the electrolyte salt. These results provide insights into the CEI layer and may potentially enlighten the development of binders and electrolytes for the high efficiency and long durability of DP-based LIBs.
干法工艺是一种用于高性能、低成本锂离子电池制造的有前景的方法，该方法使用聚四氟乙烯（PTFE）作为粘结剂。然而，关于PTFE粘结剂在阴极中的电化学稳定性以及阴极电解质界面（CEI）层产生的化学性质鲜有报道。在此，通过在含有LiPF或LiClO盐的电解质中对高负载干法加工电极进行循环，研究了CEI性质和PTFE的电化学稳定性。使用LiClO盐可以消除其他可能的氟源，从而能够研究PTFE的分解情况。在使用LiClO盐的电池中检测到LiF，证实了PTFE在阴极中发生了副反应。与LiClO相比，当使用LiPF作为电解质盐时，CEI层要厚得多。这些结果为CEI层提供了见解，并可能为基于干法工艺的锂离子电池的高效率和长耐久性的粘结剂和电解质的开发提供启示。
