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Interphases formed at battery electrodes are key to enabling energy dense charge storage by acting as protection layers and gatekeeping ion flux into and out of the electrodes. However, our current understanding of these structures and how to control their properties is still limited due to their heterogenous structure, dynamic nature, and lack of analytical techniques to probe their electronic and ionic properties in situ . In this study, we used a multi-functional scanning electrochemical microscopy (SECM) technique based on an amperometric ion-selective mercury disc-well (HgDW) probe for spatially-resolving changes in interfacial Li + during solid electrolyte interphase (SEI) formation and for tracking its relationship to the electronic passivation of the interphase. We focused on multi-layer graphene (MLG) as a model graphitic system and developed a method for ion-flux mapping based on pulsing the substrate at multiple potentials with distinct behavior ( e.g. insertion–deinsertion). By using a pulsed protocol, we captured the localized uptake of Li + at the forming SEI and during intercalation, creating activity maps along the edge of the MLG electrode. On the other hand, a redox probe showed passivation by the interphase at the same locations, thus enabling correlations between ion and electron transfer. Our analytical method provided direct insight into the interphase formation process and could be used for evaluating dynamic interfacial phenomena and improving future energy storage technologies.
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Analytical Designs: Goodwin’s Substrates as a Tool for Studying Learning
Charles Goodwin’s legacy includes a multitude of analytical tools for examining meaning making in interaction. We focus on Goodwin’s substrate—“the local, public configuration of action and semiotic resources” available in interaction used to create shared meanings (Goodwin, 2018, p. 32), gathering early career scholars to explore how research designs adapt substrate as an analytical tool for education research in diverse settings. This structured poster session examines how substrate can be used to capture a complex web of learning phenomena and support important analytical shifts, including representing learning processes, privileging members’ phenomena to address issues of equity, and understanding shifting power relations through multi-layered and multi-scaled analyses.
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- Award ID(s):
- 1742257
- PAR ID:
- 10202100
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Editor(s):
- Gresalfi, M.S.
- Date Published:
- Journal Name:
- The Interdisciplinarity of the Learning Sciences, 14th International Conference of the Learning Sciences (ICLS) 2020
- Volume:
- 3
- Page Range / eLocation ID:
- 1471-1478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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