An extended single-particle model of lithium-ion batteries based on simplified solid-liquid diffusion process

An extended lithium-ion battery model is proposed, which simplifies the solid-liquid diffusion process compared with the full-order pseudo two-dimensional (P2D) model, in order to reduce computational complexity and enhance modeling speed. To simplify the model, the three-parameter method is utilized to simplify the solid-phase diffusion process. Meanwhile, exponential fitting is applied to simplify the liquid-phase diffusion process. In addition, the average current flux is used to simplify the current exchange density at the solid-liquid interface. Finally, experiments are performed to verify the model, and experimental results demonstrate that, even though fewer parameters need to be identified, the simplified model still has satisfied accuracy under constant current and dynamic situations.