Tensorial effective transport properties of Li-ion battery separators elucidated by computational multiscale modeling

Existing battery modeling works have limitations in addressing the dependence of transport properties on local field variations and characterizing response anisotropic media. These are tackled by means a nested finite element (FE2) multiscale framework which microscale simulations employed to comprehensively characterize an medium (macroscale). The approach is applied numerical simulation processes lithium ion separators. From solution, homogenized fluxes their downscaled macroscale variables upscaled, thereby replacing otherwise assumed constitutive laws. tensorial nature effective stems from treatment. proposed verified against full-scale simulations. Several examples used demonstrate perils associated with accepted procedures, leading some cases severe discrepancies prediction quantities (from differences potential drop across separator about 27% for fixed microstructure more than 100% case evolving microstructure). Despite use simplified assumptions (e.g., synthetic microstructures), results importance description processes.