The P2D Model of a Lithium Cell with Vacancy Effect in Solid-State Diffusion

The modeling of lithium ion battery considers transport phenomenon and porous electrode kinetics such as solid or liquid state diffusion, migration, and kinetics of electrode reaction. The intercalation/deintercalation process of lithium ion at particle surface is the key to understand the charge-discharge phenomenon of lithium battery. The solid state diffusion model with a two-component diffusion term can be reduced to a simple nonlinear diffusion form and applied to the behavior of single electrode particle. The nonlinear diffusion equation shows the vacancy effect in the solid-state diffusion of the particles inside the cell is illustrated in the nonlinear diffusion equation. The simulated results of voltage versus capacity obtained at discharge rate below 0.6C agree well with the experimental data.