Challenges and numerical solutions for multi-domain and multi-physics coupling in heterogeneous lithium-ion battery model simulation

In electrochemistry, the heterogeneous model effectively characterizes the microstructural features of porous electrodes by distinctly resolving both solid and liquid phases with respective spatial distributions and interfacial interfaces. The model incorporates essential characteristics including particle size distributions and non-uniform porosity, enabling spatiotemporal representation of coupled physicochemical processes. However, modeling and numerically solving the heterogeneous model presents significant challenges. This study introduces computational solutions to critical challenges in heterogeneous lithium-ion battery simulation. (1) Distinct material phases occupy spatially resolved domains, with various phenomena occurring either bulk phases or interfaces. We develop domain decomposition/combination strategy with morphology-specific approaches. (2) Regions with similar compositions may exhibit significant variations in physical properties. Our novel transfer coefficient matrix method enables global solutions for concentration equations across interfaces with varying porosity. (3) Batteries represent inherently mass-charge coupled systems, where lithium-ion transport is driven by both electric potential and concentration gradients. The composite potential field method rigorously ensures flux continuity while resolving coupled transport mechanisms. We implement above methods to our self-developed simulation framework, rigorously validating accuracy against experimental measurements and COMSOL benchmarks. This work provides a fundamental theoretical foundation for both the development of next-generation ultra-high-performance batteries and the technological upgrade of industrial battery simulation software.