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Solid electrolytes are critical for structural batteries, combining energy storage with structural strength for applications like electric vehicles and aerospace. However, achieving high ionic conductivity remains challenging, compounded by a lack of standardized testing methodologies. This study examines the impact of experimental setups and data interpretation methods on the measured ionic conductivities of solid polymer electrolytes (SPEs). SPEs were prepared using a polymer-induced phase separation process, resulting in a bi-continuous microstructure for improved ionic transport. Eight experimental rigs were evaluated, including two- and four-electrode setups with materials like stainless steel, copper, and aluminum. Ionic conductivity was assessed using electrochemical impedance spectroscopy, with analysis methods comparing cross-sectional and surface-area-based approaches. Results showed that the four-electrode stainless steel setup yielded the highest ionic conductivity using the cross-sectional method. However, surface-area-based methods provided more consistent results across rigs. Copper setups produced lower conductivities but exhibited less data variability, indicating their potential for reproducible measurements. These findings highlight the critical influence of experimental design on conductivity measurements and emphasize the need for standardized testing protocols. Advancing reliable characterization methods will support the development of high-performance solid electrolytes for multifunctional energy storage applications.
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Chemically inert covalently networked triazole-based solid polymer electrolytes for stable all-solid-state lithium batteries
Covalently networked polymers offer desirable non-crystallinity and mechanical strength for solid polymer electrolytes (SPEs), but the chemically active cross-links involved in their construction could deteriorate the compatibility with high-energy cathode materials that are electrophilic and/or in the charged state. Herein we reveal a strong dependence of cyclability of such cathodes on the reactivity of covalently networked SPEs and demonstrate a polymer design that renders these SPEs chemically inert. We designed and synthesized two hybrid networks, both with polyethylene oxide as the cation conducting component and polyhedral oligomeric silsesquioxane as the branch point, but respectively use alkylamino and chemically inert triazole groups as cross-links. All-solid-state cells using the alkylamino-containing SPE underwent rapid degradation while cells using triazole SPEs showed stable cycling.
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- Award ID(s):
- 1809866
- PAR ID:
- 10161614
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 7
- Issue:
- 34
- ISSN:
- 2050-7488
- Page Range / eLocation ID:
- 19691 to 19695
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9ta05885k
