skip to main content


Title: Quantification of ionic transport within thermally-activated batteries using electron probe micro-analysis

The transient transport of electrolytes in thermally-activated batteries is studied in this paper using electron probe micro-analysis (EPMA), demonstrating the robust capability of EPMA as a useful tool for studying and quantifying mass transport within porous materials, particularly in difficult environments where classical flow measurements are challenging. By tracking the mobility of bromine and potassium ions from the electrolyte stored within the separator into the lithium silicon anode and iron disulfide cathode, we are able to quantify the transport mechanisms and physical properties of the electrodes including permeability and tortuosity. Due to the micron to submicron scale porous structure of the initially dry anode, a fast capillary pressure driven flow is observed into the anode from which we are able to set a lower bound on the permeability of 10 -1 mDarcy. The transport into the cathode is diffusion-limited because the cathode originally contained some electrolyte before activation. Finally, using a transient one-dimensional diffusion model, we estimate the tortuosity of the cathode electrode to be 2.8 ± 0.8.
 [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0378-7753; 614045
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Power Sources
Additional Journal Information:
Journal Volume: 320; Journal ID: ISSN 0378-7753
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
25 ENERGY STORAGE; thermal battery; electron probe micro-analysis; electrolyte; mass transport; tortuosity; diffusion; permeability
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1425695