Consistent Coupling of Electrodynamics to Thermodynamics for Batteries

• Applicant: Dr. Stefanie Braun
• Subject Area: Chemical and Thermal Process Engineering
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 517510462

Batteries and other polarisable media contain moving charge carriers that are subject to electromagnetic forces exerted by the electrodes and the other particles. In order to model the resulting particle motion self-consistently, the thermodynamic conservation equations for mass, momentum and energy are combined with the Maxwell equations describing the evolution of electromagnetic fields. The question how to correctly couple these two different fields of physics has not been answered satisfactorily yet. This project focuses on the derivation of a consistent macroscopic theory for the moving charges. To avoid contradictions, the coupling of the two subsystems will already be realised on the microscopic particle scale, ensuring that each particle's total momentum and energy, including electromagnetic contributions, are conserved. The resulting equations are then coarse-grained to obtain the macroscopic description. An entropy principle will be applied to find a closure for the system.

• DFG Programme: Research Grants