Publication Date:
2016-10-19
Description:
The development of stress and fracture in Si-based anodes for lithium-ion batteries is strongly affected by lithiation-induced plasticity. Recent experiments indicate that the nature of plasticity of lithiated silicon is rate-dependent. We establish a theoretical model to capture the viscoplastic mechanical behavior of Si anodes during two-phase lithiation. It is demonstrated that the lithiation-induced stress field is determined by the migration speed of the Li- Li 3.75 Si interface and the characteristic size of the Si anodes. If experimentally measured interface velocity data in Si nanoparticle are available, the mechanistic model can directly predict the rate-sensitive spatiotemporal stress profile, which is hardly measured in experiments.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
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