Enhancement of ionic transport characteristics and cell performance through multi-layered separator microstructure in Li-ion cells

Ionic transport characteristics of separators significantly influence li-ion cell performance. In order to maximize the spatiotemporal ionic dynamics, the present study probed the multi-layered separator microstructure, which can lead to an increment in cell performance for discharging and charging mechanisms. The numerical simulations are performed considering the one-dimensional Newman model to study the effect of multi-layered porosity at different C-rates. Our study reports that the capacity strongly depends on the separator’s porosity distribution. Furthermore, the variation of average capacity among different separator porosity configurations becomes more evident with an increment in the C rate and charging behavior. Additionally, a strong interplay of separator porosity and its distribution on temporal cell characteristics, viz., electrolyte salt concentration and total power dissipation density, is revealed for the charging-discharging cycle. Further, the cell performance characteristics are found to be best when separator porosity is higher adjacent to the electrode-separator interphase for the charging-discharging cycle. The present study established the importance of multi-layered separator microstructure in improving ionic dynamics and cell performance.