TY - THES

T1 - A characterization program for cell spacer materials

T2 - unveiling key performance parameters for advanced battery stack assemblies

AU - Liu, Daniel Tianhao

N1 - embargoed until 01-10-2029

PY - 2024

Y1 - 2024

N2 - Batteries, as the heart of electric vehicles, significantly determine their range, performance, and lifespan. As a central component of modern batteries, cell spacers act as physical barriers between individual battery cells. They provide electrical insulation and play a key role in the mechanical and thermal stability of the entire battery. The choice of materials for these components therefore has a major impact on the safety and reliability of electric vehicles, and thus on the further development of electromobility. In this work, a program for the mechanical characterization of cell spacer materials was developed. The program captures the behavior of the components under mechanical loads they experience throughout their entire lifecycle through various testing methods. To replace costly physical prototypes of cell spacers with virtual ones in the future, the measured material behavior was further modeled using the Finite Element Method (FEM). The material testing procedure and the applicability of different material models were demonstrated in this work using three common materials for cell spacers: silicone foam, silicone rubber, and aerogel composite. The materials exhibited significantly different properties in terms of compressibility and degradation under cyclic loading during testing. This is also reflected in the selection of the most suitable material models, which differ for each of the materials considered. Furthermore, the simulation of the aerogel composite revealed that more complex material behavior requires more sophisticated modeling approaches, which can only be realized through simulation subroutines.

AB - Batteries, as the heart of electric vehicles, significantly determine their range, performance, and lifespan. As a central component of modern batteries, cell spacers act as physical barriers between individual battery cells. They provide electrical insulation and play a key role in the mechanical and thermal stability of the entire battery. The choice of materials for these components therefore has a major impact on the safety and reliability of electric vehicles, and thus on the further development of electromobility. In this work, a program for the mechanical characterization of cell spacer materials was developed. The program captures the behavior of the components under mechanical loads they experience throughout their entire lifecycle through various testing methods. To replace costly physical prototypes of cell spacers with virtual ones in the future, the measured material behavior was further modeled using the Finite Element Method (FEM). The material testing procedure and the applicability of different material models were demonstrated in this work using three common materials for cell spacers: silicone foam, silicone rubber, and aerogel composite. The materials exhibited significantly different properties in terms of compressibility and degradation under cyclic loading during testing. This is also reflected in the selection of the most suitable material models, which differ for each of the materials considered. Furthermore, the simulation of the aerogel composite revealed that more complex material behavior requires more sophisticated modeling approaches, which can only be realized through simulation subroutines.

KW - Batterie-Zellen-Abstandhalter

KW - Materialauswahl

KW - Thermo-mechanische Charakterisierung

KW - Methodenentwicklung

KW - Kompressibilität

KW - Finite-Elemente-Simulation

KW - battery-cell-spacers

KW - material selection

KW - thermo-mechanical characterization

KW - method development

KW - compressibility

KW - finite-element-simulation

U2 - 10.34901/mul.pub.2024.250

DO - 10.34901/mul.pub.2024.250

M3 - Master's Thesis

ER -