Physics-Based Reduced Order Model for Sodium-Ion Batteries

Sodium-ion batteries (SIBs) are emerging as promising energy storage systems. SIBs share similar chemistry and performance metrics with lithium-ion batteries (LIBs), the workhorse energy storage technology. Abundant availability of sodium and its even distribution across the globe make SIBs a better alternative to LIBs. Electrochemical models enabling simulation of batteries help study performance and various parameters of batteries for a variety of operating conditions. Reduced order electrochemical models can be used to study batteries to obtain quick insights, especially, at lesser computational cost. In this work, we present a reduced order model for SIBs based on the single particle assumption. We validate the single particle model (SPM) by comparing the results with experimental data and predictions of detailed pseudo-two-dimensional (P2D) model. The SPM shows good accuracy in predicting voltage profiles over a range of discharge current densities. We further discuss the regime of operation where the SPM predictions deviate from that of the P2D model. Our study suggests that the SPM can be used as a viable alternative to the P2D model to design and test SIBs.