Towards a more realistic battery model: variational multiscale modeling of Li-ion batteries

Modeling and simulation of Li-ion batteries have been carried out across different disciplines to investigate various aspects from electrochemical performance to design optimization simulation. The missing part in the simulation of battery systems is to incorporate ongoing microscale phenomena into numerical problems governing macroscale behaviors, which is necessary to be accounted for the goal of having a more realistic battery model. As one of the first attempts, this study employs variational multiscale method (VMM) for the analysis of Li-ion batteries. The main advantage of VMM lies in its computational efficiency compared with the conventional methods while decomposing the total response of the system linearly into macro- and microscale components without assuming scale separation. VMM evaluates the microscale response semi-analytically through variational projection. With the determined microscale response, through VMM modeling, our model resolves to consider the structural heterogeneity to capture a total response of a battery.