Jump to main content
Jump to site search

Volume 199, 2017
Previous Article Next Article

Direct observation of active material interactions in flowable electrodes using X-ray tomography

Author affiliations


Understanding electrical percolation and charging mechanisms in electrochemically active biphasic flowable electrodes is critical for enabling scalable deionization (desalination) and energy storage. Flowable electrodes are dynamic material systems which store charge (remove ions) and have the ability to flow. This flow process can induce structural changes in the underlying material arrangement and result in transient and non-uniform material properties. Carbon-based suspensions are opaque, multi-phase, and three dimensional, and thus prior characterization of the structural properties has been limited to indirect methods (electrochemical and rheology). Herein, a range of mixed electronic and ionically conducting suspensions are evaluated to determine their static structure, function, and properties, utilizing synchrotron radiation X-ray tomographic microscopy (SRXTM). The high brilliance of the synchrotron light enables deconvolution of the liquid and solid phases. Reconstruction of the solid phase reveals agglomeration cluster volumes between 10 μm3 and 103 μm3 (1 pL) for low loaded samples (5 wt% carbon). The largest agglomeration cluster in the low loaded sample (5 wt%) occupied only 3% of the reconstructed volume whereas samples loaded with 10 wt% activated carbon demonstrated electrically connected clusters that occupied 22% of the imaged region. The highly loaded samples (20 wt%) demonstrated clusters of the order of a microliter, which accounted for 63–85% of the imaged region. These results demonstrate a capability for discerning the structural properties of biphasic systems utilizing SRXTM techniques, and show that discontinuity in the carbon particle networks induces decreased material utilization in low-loaded flowable electrodes.

Back to tab navigation

Supplementary files

Publication details

The article was received on 26 Nov 2016, accepted on 16 Jan 2017 and first published on 19 Jan 2017

Article type: Paper
DOI: 10.1039/C6FD00243A
Citation: Faraday Discuss., 2017,199, 511-524
  •   Request permissions

    Direct observation of active material interactions in flowable electrodes using X-ray tomography

    K. B. Hatzell, J. Eller, S. L. Morelly, M. H. Tang, N. J. Alvarez and Y. Gogotsi, Faraday Discuss., 2017, 199, 511
    DOI: 10.1039/C6FD00243A

Search articles by author