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Reactive metals are known to electrodeposit with irregular morphological features on planar substrates. A growing body of work suggest that multiple variables: composition, mechanics, structure, ion transport properties, reductive stability, and interfacial energy of interphases, formed either spontaneously or by design on the metal electrode play important but differentiated roles in regulating these morphologies. We examine the effect of fluorinated thermoset polymer coatings on Li deposition by means of experiment and theoretical linear stability analysis. By tuning the chemistry of the polymer backbone and side chains, we investigate how physical and mechanical properties of polymeric interphases influence Li electrodeposit morphology. It is found that an interplay between elasticity and diffusivity leads to an optimum interphase thickness and that higher interfacial energy augments elastic stresses at a metal electrode to prevent out-of-plane deposition. These findings are explained using linear stability analysis of electrodeposition and provide guidelines for designing polymer interphases to stabilize metal anodes in rechargeable batteries.
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Analysis of thin layers with interphases
Bonds between distinct solids rarely present sharp discontinuities in mechanical properties. Particularly in the case of the bonds between polymers with metals, ceramics, and semiconductors, interphase regions are formed whose mechanical behavior differs from that of the bulk polymer. This paper examines the potential of detecting interphases associated with thin polymer layers under axial and shear loading. We demonstrate that a recent asymptotic analysis co-developed by one of our honorees can be extended and holds in the presence of interphases. As a result, we are able to establish the conditions under which interphases may be detected when thin layers are loaded in tension and shear. Further, our analysis suggests that interphases may significantly reduce the high degree of triaxiality that has long been associated with thin, nearly incompressible layers.
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- Award ID(s):
- 2110526
- PAR ID:
- 10561853
- Publisher / Repository:
- Science Direct
- Date Published:
- Journal Name:
- European Journal of Mechanics - A/Solids
- Volume:
- 100
- Issue:
- C
- ISSN:
- 0997-7538
- Page Range / eLocation ID:
- 104549
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.euromechsol.2022.104549
