Title :
Investigation of projection-based model-reduction techniques for solid-phase diffusion in Li-ion batteries
Author :
Mayhew, Christopher ; Wei He ; Kroener, Christoph ; Klein, Reinhard ; Chaturvedi, Nalin ; Kojic, Aleksandar
Author_Institution :
Res. & Technol. Center, Robert Bosch, Palo Alto, CA, USA
Abstract :
In this work, we apply the projection-based model-reduction framework for PDEs of [1] to the diffusion process governing the intercalation of lithium ions into spherical particles that appears in electrochemical models of Li-ion batteries. We first invoke the projection framework with different projections (the so-called natural-i.e. Galerkin-and volume-averaging projections-NP and VAP, respectively) and different basis sets (even monomials and eigenfunctions of the PDE) to arrive at different reduced models, which we then benchmark in a dimensionless frequency-domain setting. Surprisingly, we find that VAP of an even monomial basis yields an unstable reduced model for anything but the lowest order; however, NP yields suitable results for the basis sets and orders considered. Furthermore, we find that the NP-eigenfunction combination makes for a slow convergence when compared to NP with even monomials; however, room for further improvement is seen when compared with a balanced truncation, which is not applicable in the nonlinear setting of concentration-dependent diffusivity.
Keywords :
Galerkin method; convergence; eigenvalues and eigenfunctions; frequency-domain analysis; reduced order systems; secondary cells; Galerkin projection; NP eigenfunction; PDE monomial VAP; concentration dependent diffusivity nonlinear setting; convergence; frequency domain; lithium ion battery electrochemical model; lithium ion intercalation; solid phase diffusion process; spherical particles; unstable reduced model; volume averaging projection; Approximation methods; Batteries; Boundary conditions; Convergence; Eigenvalues and eigenfunctions; Frequency-domain analysis; Mathematical model; Automotive; Power systems; Reduced order modeling;
Conference_Titel :
American Control Conference (ACC), 2014
Conference_Location :
Portland, OR
Print_ISBN :
978-1-4799-3272-6
DOI :
10.1109/ACC.2014.6859408