Efficient Reformulation of Linear and Nonlinear Solid-Phase Diffusion in Lithium-ion Battery Models using Symmetric Polynomials: Mass Conservation and Computational Efficiency

Lithium-ion batteries are typically modeled using porous electrode theory coupled with various transport and reaction mechanisms, along suitable discretization or approximations for the solid-phase diffusion equation. The equation represents main computational burden typical pseudo-2-dimensional (p2D) models since these equations in pseudo r -dimension must be solved at each point grid. This substantially increases complexity of model as well time. Traditional approaches towards simplifying possess certain significant limitations, especially modeling emerging materials which involve phase changes variable diffusivities. A computationally efficient representation is discussed this paper based on symmetric polynomials Orthogonal Collocation Galerkin formulation (weak form). systematic approach provided to increase accuracy approximation (p form finite element methods) enable simulation a minimal number semi-discretized equations, ensuring mass conservation even non-linear problems involving These methods then demonstrated by incorporation into full p2D model, illustrating their advantages simulating high C-rates short-time dynamic operation batteries.