Effect of electrode compression on the wettability of lithium-ion batteries

Using the multiphase lattice Boltzmann method (LBM), the electrolyte transport dynamics in the two-dimensional electrode structure of a lithium-ion battery are simulated. The effect of the compression ratio of a porous electrode on wettability is explored with respect to variations of porosity and particle shape. The electrolyte distribution in the electrode and the electrolyte saturation profile are examined in order to evaluate the wetting capability at various compression ratios. The results show that wettability in the electrode decreases as the compression ratio increases. In a highly compressed electrode, the through-plane permeation of liquid electrolyte is small. Thus, the electrolytes are mainly observed at the interface of the electrode and separator. The anode has lower wettability than the cathode due to the deformation of particle shape during the manufacturing process. Therefore, particle shape has a strong effect on wettability. The two-dimensional LBM approach used in this study characterizes the electrolyte transport phenomena inside the electrode and allows us to compare the wettability between the cathode and anode at various compression ratios.