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

Area of Science:

• Battery Technology
• Thermal Management
• Mathematical Modeling

Background:

• Accurate internal temperature estimation is crucial for lithium-ion battery safety and performance.
• Pouch-type batteries present unique thermal challenges due to their geometry.
• Existing methods often struggle with limited sensor data and model uncertainties.

Purpose of the Study:

• To develop an internal temperature estimation strategy for pouch-type lithium-ion batteries.
• To address challenges posed by space-dependent diffusivity and in-domain uncertainty.
• To utilize limited distributed linear measurements effectively.

Main Methods:

• A 2-D semilinear partial differential equation (PDE) model with space-dependent diffusivity was employed.
• The domain was divided into subdomains based on sensor placement.
• A Luenberger-type PDE observer was designed for temperature estimation.
• Lyapunov functional method and linear matrix inequalities (LMIs) were used to establish stability.
• A robust estimation strategy was developed for systems with in-domain uncertainty, ensuring input-to-state stability (ISS).

Main Results:

• The proposed Luenberger-type PDE observer ensures exponential stability for the estimation error system in the absence of uncertainty.
• The robust estimation strategy guarantees input-to-state stability (ISS) for the observer error system in the presence of in-domain uncertainty.
• Simulation results validated the effectiveness of both the uncertainty-free and robust estimation methods.

Conclusions:

• The developed PDE-based observer provides an effective strategy for internal temperature estimation in pouch-type lithium-ion batteries.
• The robust approach successfully handles in-domain uncertainties, enhancing reliability.
• The findings contribute to improved battery thermal management and safety.