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Among anode materials for Li-ion batteries, Si is known for high theoretical capacity, low cost, large volume change, relatively fast capacity fade and significant stress-potential coupling. This article shows that a Li(Ni0.5Co0.2Mn0.3)O2-Si battery can store energy, actuate with Si volume change and sense with stress-potential coupling. Experiments are conducted in an electrolyte-filled chamber with a glass window with Li(Ni0:5Co0:2Mn0:3)O2 cathodes and Si composite anodes. The Si anodes are single-side coated on Cu current collector with Si nanoparticles, polyacrylic acid binder and conductive carbon black in a porous composite structure. During charging, the battery stores energy, Li inserts in the cantilevered Si anodes and the cantilevers bend laterally. Discharging the battery releases the stored energy and straightens the Si cantilevers. Imposing deformation on the Si cantilevers at a fixed state of charge causes bending stress in the composite coating and a change in the open circuit potential. Testing at 1Hz confirms that the Si composite responds to dynamic stress variations and with almost no phase lag, indicating the bandwidth of the stress-potential coupling in Si composite anodes is at least 1Hz.
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This content will become publicly available on October 1, 2026
Uncertainty Quantification of Silicon Anode Capacity Fading with Multiple Interactive Degradation Mechanisms Using Physics-Informed Gaussian Process Modeling
The surging demand for Li-ion batteries (LIBs) has started a quest for innovations in their design and technology. A notable improvement in this regard involves the use of Silicon (Si) as the active anode material in LIBs. However, a major challenge stopping its widespread adoption is the considerable volume change experienced by Si during the lithiation-delithiation process, leading to volumetric stress-induced capacity degradation. This study identifies three primary capacity fade mechanisms in these LIBs: volumetric-stress-induced cracking and delamination, along with the growth of the solid electrolyte interface (SEI) during charging and discharging cycles. These mechanisms are influenced by battery design and operating conditions, such as Si anode thickness, ambient working temperature, and charging rate, introducing uncertainty into the battery’s degradation rate. In this study, multiple finite element (FE) models are constructed to simulate capacity degradation resulting from these three capacity fade mechanisms and their predictions are validated against experimental data. To address the computational demands of multiple FE models simulating capacity degradation from these fade mechanisms, a Gaussian Process Regression (GPR) surrogate model is developed. This GPR model efficiently predicts capacity fade and is validated for accuracy. Subsequently, the GPR model is used in an uncertainty quantification study that is focused on the battery’s design and operating conditions. The objective is to pinpoint the factors that exert the most significant influence on capacity degradation in Si anode-based LIBs.
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- Award ID(s):
- 2037898
- PAR ID:
- 10654472
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 172
- Issue:
- 10
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- 100543
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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