High Tensile Alloy of Copper to Mitigate Current Collector Deformation in Silicon Electrodes for Lithium-Ion Batteries

Journal Article · Wed Jul 30 04:00:00 EDT 2025 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2025.237853· OSTI ID:2575436

Salpekar, Devashish ^[1]; Preimesberger, Juliane ^[2]; Rodrigues, Marco-Tulio ^[1]; Singh, Avtar ^[2]; Verma, Ankit ^[2]; Trask, Stephen ^[1]; Colclasure, Andrew ^[2]; Coyle, Jaclyn ^[2]; Jansen, Andrew ^[1]; Abraham, Daniel ^[1]; Lu, Wenquan ^[1]

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1. Argonne National Laboratory
2. National Renewable Energy Lab., Golden, CO (United States)

The volumetric changes of silicon electrodes, along with the strong adhesive properties of certain binders, can lead to plastic deformation of the current collector and create damage in the electrode coating. Here, we report a detailed study of silicon coatings on a high-tensile alloy (HTA) foil of copper with strength over twice that of conventional copper foils. The HTA current collectors with high mechanical strength can mitigate plastic deformation upon continuous cycling. At moderate areal capacities (2.5-3 mAh cm-2), conventional copper foils show significant wrinkling after only a few electrochemical cycles, whereas the HTA foils remain intact. We demonstrate viability of the HTA foils in large format xx6395 pouch cells, in which the HTA current collectors remain intact even at an areal capacity of 4.5 mAh cm-2; in contrast, wrinkles form in conventional copper current collectors increasing the likelihood of lithium plating. Computational studies show that stresses generated during cycling of silicon electrodes are very high in the current collector and at the current collector-coating interface, explaining the wrinkling of conventional Cu foils. Our studies highlight importance of current collector to solve the electrochemical and chemo-mechanical performance challenges associated with high-loading silicon electrodes.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Vehicle Technologies Office
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 2575436
• Report Number(s): NREL/JA-5700-92144
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Vol. 655
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
NMC811
chemo-mechanical degradation
electrochemistry
pouch cell
strain
stress