Dynamic mathematical characterization of electro-thermo-mechanical coupling behaviors in lithium-ion batteries

Hits:

Impact Factor:6.9

DOI number:10.1016/j.applthermaleng.2026.129791

Journal:Applied Thermal Engineering

Key Words:lithium-ion batteries; Electro-thermal-mechanical coupling behaviors; Dynamic mathematical characterization

Abstract:The strong cross-coupling among electrical, thermal, and mechanical behaviors in lithium-ion batteries pose significant challenges to accurate dynamic mathematical characterization. The core innovation lies in developing an incremental integration of existing electro, thermal, mechanical models, to dynamically characterize of electro-thermal-mechanical coupling behaviors of lithium-ion batteries. The electrical behaviors are captured by a first-order RC equivalent circuit model, the thermal behaviors are captured by a lumped-parameter thermal model, and the mechanical behaviors are captured by an equivalent strain model based on the solid-state diffusion theory and the thermal expansion theory. The coupling model parameters are identified online via the Forgetting Factor Recursive Least Squares. Experimental results under FUDS and WLTC, across various ambient temperatures and battery aging levels indicate that, the Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) of the voltage estimation results remain below 20 mV and 35 mV, the MAE and RMSE of the temperature estimation results remain below 0.1 ◦C and 0.15 ◦C, the MAE and RMSE of the strain estimation results remain below 2.5με and 3.0με. Furthermore, the more innovation conclusion is that, the thermal resistance exhibits an overall increasing trend as the battery aging, but no clear dependence of it on the ambient temperature is identified. The dynamic temperature strain coefficient shows a notable dependence on the battery aging level, the average standard deviations of the it for fresh and aged batteries are 0.12με and 0.25με, respectively, representing a more than twofold difference. In contrast, the dynamic SOC strain coefficient does not demonstrate such a trend.

Note:中科院1区Top

Co-author:Changpeng Tan

First Author:Muyao Wu

Indexed by:Journal paper

Correspondence Author:Li Wang

Document Code:129791

Discipline:Engineering

Document Type:J

Volume:289

ISSN No.:1359-4311

Translation or Not:no

Date of Publication:2026-01-17

Included Journals:SCI、EI

Links to published journals:https://www.sciencedirect.com/science/article/abs/pii/S1359431126000992