This study demonstrates fluorine‐free cross‐linked (meth)acrylate polymers as alternatives to polyvinylidene fluoride (PVDF) in LiNi0.33Mn0.33Co0.33O2(NMC111) cathodes. We determine the effects of thermal initiator content, polymer content, and curing environment for two polymer chemistries: a flexible acrylate polymer, and a stiff methacrylate polymer. Electrodes are manufactured and tested for final electrochemical performance and mechanical properties. The results show that the flexible acrylate polymer exhibits higher rate capability compared to the stiff methacrylate polymer because calendering fractures the brittle network of stiff polymer. Electrode adhesion to the current collector and cohesion between particles are found to be a strong function of thermal initiator ratio and oxygen inhibition. Furthermore, there exists an optimal binder concentration that maximizes rate capability performance. Under the right conditions, the two polymers exhibit comparable performance to PVDF electrodes. These results provide important implications for designing cross‐linked polymers as cathode binder alternatives to PVDF.
This content will become publicly available on October 1, 2025
Electronic connections between active material particles and the conductive carbon binder domain govern high-energy commercial Li-ion batteries' rate capability and lifetime (LIB). This work develops an in situ electrochemical fluorescent microscopy (EFM) technique that maps fluorescence intensity to these local electronic connections. Specifically, rapid redox kinetics of an electrofluorophore translates to reaction distributions limited by the electronic accessibility of battery electrode regions and individual active material particles. This technique can visualize hot spots, dead zones, and isolated particles on the electrode surface. EFM characterization of a series of LiNi0.33Mn0.33Co0.33O2electrodes across processing parameters finds a significant negative correlation between the number of disconnected active particles and the rate capability. This low-cost technique provides quantitative mesoscale characterization of commercial LIB electrodes with fast throughput (<60 s) to facilitate rapid research and development and provide manufacturing quality control.
more » « less- Award ID(s):
- 1751553
- PAR ID:
- 10555879
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 171
- Issue:
- 10
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- 100512
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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