Internal Temperature Estimation of Pouch-Type Lithium-Ion Battery by a 2-D Semilinear PDE Model With Space-Dependent Diffusivity

This article aims to propose an internal temperature estimation strategy for pouch-type lithium-ion battery using a 2-D semilinear partial differential equation (PDE) model with space-dependent diffusivity and in-domain uncertainty. The distributed linear measurements are considered, where only limited linear information is measured. Initially, we divide the interested domain into several subdomains based on the number of sensors. A Luenberger-type PDE observer is then designed for battery internal temperature estimation by the uncertainty-free plant model, and the exponential stability of corresponding estimation error system is established via the Lyapunov functional method and linear matrix inequalities (LMIs). Moreover, when in-domain uncertainty is presented, a robust internal temperature estimation strategy is developed to ensure that the corresponding uncertain observer error systems are input-to-state stable (ISS). Simulation results are finally provided to verify the effectiveness of the proposed methods.