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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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This content will become publicly available on February 1, 2027
Design of bi-continuous structural battery electrolyte using a virtual temperature constrained topology optimization
Abstract Structural Battery Composites (SBC) are a new class of multifunctional materials that simultaneously provide structural load-bearing capabilities as well as electrochemical energy storage. By combining these functionalities, the weight and volume of energy storage systems can be reduced. In this work, a multiphysics, multi-objective topology optimization framework is used to design the Structural Battery Electrolyte (SBE) of the SBC. The objectives considered are the minimization of compliance and maximization of effective ionic conductivity. The multi-objective formulation is implemented using the Normalized-Normal Constraint method. This framework uses the finite element method to evaluate the structural and thermal responses and ResNet, a reduced order model, to find the effective ionic conductivity. The sensitivities of all physics are determined analytically using the adjoint sensitivity method. Previous studies have implemented topology optimization for designing SBE; however, these methodologies do not guarantee a bi-continuous design. Bi-continuous domains of the SBE are necessary for efficient ion transport. In this study, a virtual temperature constraint is used in conjunction with the topology optimization framework to prevent electrolyte islands from forming in the design domain. By doing so, bi-continuous behavior of the SBE microstructure can be enforced. Several numerical studies are conducted to demonstrate the capabilities of this framework.
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- Award ID(s):
- 2143422
- PAR ID:
- 10703760
- Publisher / Repository:
- Springer/Structural and Multidisciplinary Optimization
- Date Published:
- Journal Name:
- Structural and Multidisciplinary Optimization
- Volume:
- 69
- Issue:
- 2
- ISSN:
- 1615-147X
- Subject(s) / Keyword(s):
- Topology optimization· Structural battery electrolyte· Virtual temperature constraint· Structural battery composite
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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