Sensitivity-based interval PDE observer for battery SOC estimation

Complex multi-partial differential equation (PDE) electrochemical battery models are characterized by parameters that are often difficult to measure or identify. This parametric uncertainty influences the state estimates of electrochemical model-based observers for applications such as state-of-charge (SOC) estimation. This paper develops a sensitivity-based interval observer that maps bounded parameter uncertainty to state estimation intervals, within the context of electrochemical PDE models and SOC estimation. Theoretically, this paper extends the notion of interval observers to PDE models using a sensitivity-based approach. Practically, this paper quantifies the sensitivity of battery state estimates to parameter variations, enabling robust battery management schemes.