Dendrite Suppression by Shock Electrodeposition in Charged Porous Media
Author(s)
Han, Jihyung; Wang, Miao; Bai, Peng; Brushett, Fikile R; Bazant, Martin Z
DownloadDendrite suppression.pdf (2.122Mb)
PUBLISHER_CC
Publisher with Creative Commons License
Creative Commons Attribution
Terms of use
Metadata
Show full item recordAbstract
It is shown that surface conduction can stabilize electrodeposition in random, charged porous media at high rates, above the diffusion-limited current. After linear sweep voltammetry and impedance spectroscopy, copper electrodeposits are visualized by scanning electron microscopy and energy dispersive spectroscopy in two different porous separators (cellulose nitrate, polyethylene), whose surfaces are modified by layer-by-layer deposition of positive or negative charged polyelectrolytes. Above the limiting current, surface conduction inhibits growth in the positive separators and produces irregular dendrites, while it enhances growth and suppresses dendrites behind a deionization shock in the negative separators, also leading to improved cycle life. The discovery of stable uniform growth in the random media differs from the non-uniform growth observed in parallel nanopores and cannot be explained by classic quasi-steady “leaky membrane” models, which always predict instability and dendritic growth. Instead, the experimental results suggest that transient electro-diffusion in random porous media imparts the stability of a deionization shock to the growing metal interface behind it. Shock electrodeposition could be exploited to enhance the cycle life and recharging rate of metal batteries or to accelerate the fabrication of metal matrix composite coatings.
Date issued
2016-06Department
Massachusetts Institute of Technology. Department of Chemical Engineering; Massachusetts Institute of Technology. Department of MathematicsJournal
Scientific Reports
Publisher
Nature Publishing Group
Citation
Han, Ji-Hyung, Miao Wang, Peng Bai, Fikile R. Brushett, and Martin Z. Bazant. “Dendrite Suppression by Shock Electrodeposition in Charged Porous Media.” Scientific Reports vol. 6, no. 28054, 2016, pp. 1-12.
Version: Final published version
ISSN
2045-2322