Clarifying the Effect of Pressure on Performance in Lithium-Ion Batteries

Lithium-ion batteries experience both reversible and irreversible swelling forces during cycling, which play a crucial role in their mechanical behavior and overall performance. This study investigates the impact of swelling forces on battery performance, focusing on how increased expansion forces reduce electrode porosity, consequently affecting electrolyte wetting within the battery. Additionally, the study explores the influence of swelling forces on battery kinetics by integrating experimental studies with theoretical modeling. The results indicate that increased pressure leads to heightened polarization, which elevates the liquid phase potential, decreases the anode potential, and causes the battery cutoff voltage to be reached more rapidly. These changes negatively impact battery performance and raise the risk of lithium dendrite formation. The findings of this research contribute to the design and application of safer, high-performance batteries.