Data-Driven Nonlinear Identification of Li-Ion Battery Based on a Frequency Domain Nonparametric Analysis
This work addresses the need for accurate battery models in electric vehicles, but the approach is incremental as it applies existing nonlinear system identification methods to a specific domain.
The paper proposes a data-driven polynomial nonlinear state-space model for Li-ion batteries, validated through frequency domain nonparametric analysis, achieving accurate identification of battery dynamics at the boundary of linear and nonlinear regimes.
Lithium ion batteries are attracting significant and growing interest, because their high energy and high power density render them an excellent option for energy storage, particularly in hybrid and electric vehicles. In this brief, a data-driven polynomial nonlinear state-space model is proposed for the operating points at the cusp of linear and nonlinear regimes of the battery's electrical operation, based on the thorough nonparametric frequency domain characterization and quantification of the battery's behavior in terms of its linear and nonlinear behavior at different levels of the state of charge.