@article{stamps_eischen_huang_2016, title={Particle- and crack-size dependency of lithium-ion battery materials LiFePO₄}, volume={3}, ISSN={2372-0484}, url={http://dx.doi.org/10.3934/matersci.2016.1.190}, DOI={10.3934/matersci.2016.1.190}, abstractNote={Lithium-ion batteries have become a widely-used commodity for satisfying the world’s mobile power needs. However, the mechanical degradation of lithium-ion batteries initiated by micro cracks is considered to be a bottleneck for advancing the current technology. This study utilizes a finite element method-based virtual crack closure technique to obtain particle- and crack-size-dependent estimates of mixed-mode energy release rates and stress intensity factors. Interfacial cracks in orthotropic bi-materials are considered in the current study, whereas the crack extension along the interface is assumed. The results show that energy release rate, stress intensity factor, and the propensity of crack extension are particle- and crack-size- dependent. In particular, our results show that for smaller plate-like LiFePO 4 particles (100 nm × 45 nm), a crack has lesser tendency to extend if crack-to-particle size is less than 0.2, and for 200 nm × 90 nm particles, similar results are obtained for crack-to-particle sizes of less than 0.15. However, for larger particles (500 nm × 225 nm), it requires an almost flawless particle to have no crack extension. Therefore, the current study provides insight into the fracture mechanics of LiFePO 4 and the associated crack-to-particle size dependency to prevent crack extensions.}, number={1}, journal={AIMS Materials Science}, publisher={American Institute of Mathematical Sciences (AIMS)}, author={Stamps, Michael A. and Eischen, Jeffrey W. and Huang, Hsiao-Ying Shadow}, year={2016}, pages={190–203} }
 @inproceedings{chiu huang_stamps_huang_2013, title={Mechanics of diffusion-induced fractures in lithium-ion battery materials}, volume={1541}, booktitle={Materials Research Society Symposium Proceedings}, author={Chiu Huang, C.-K. and Stamps, M. and Huang, H.-Y. S.}, year={2013} }
 @inproceedings{stamps_huang_2012, place={Houston, TX}, title={Mixed Modes Fracture and Fatigue Evaluation for Lithium-ion Batteries}, DOI={10.1115/imece2012-88037}, abstractNote={Lithium ion batteries have become a widely known commodity for satisfying the world’s mobile energy storage needs. But these needs are becoming increasingly important, especially in the transportation industry, as concern for rising oil prices and environmental impact from fossil fuels are pushing for deployment of more electric vehicles (EV) or plug in hybrid-electric vehicles (PHEV) and renewable energy sources. The objective of this research is to obtain a fundamental understanding of degradation mechanisms and rate-capacity loss in lithium-ion batteries through fracture mechanics and fatigue analysis approaches. In this study we follow empirical observations that mechanical stresses accumulate on electrode materials during the cycling process. Crack induced fracturing will then follow in the material which electrical contact surface area is degraded and over capacitance of the battery reduces. A fatigue analysis simulation is applied using ANSYS finite element software coupled with analytical models to alleviate these parameters that play the most pivotal roles in affecting the rate-capacity and cycle life of the lithium-ion battery. Our results have potential to provide new models and simulation tools for clarifying the interplay of structure mechanics and electrochemistry while offering an increased understanding of fatigue degradation mechanisms in rechargeable battery materials. These models can aid manufacturers in the optimization of battery materials to ensure longer electrochemical cycling life with high-rate capacity for improved consumer electronics, electric vehicles, and many other military or space applications.}, booktitle={Proceedings of the ASME International Mechanical Engineering Congress and Exposition}, author={Stamps, Michael A. and Huang, Hsiao-Ying Shadow}, year={2012}, pages={97–103} }