Thermal Management Simulation of Liquid-Cooled Energy Storage Batteries Using a Reduced-Order Model

A linear time-invariant (LTI) reduced-order model (ROM) based on 3D CFD offers high accuracy for simulating energy storage battery thermal behavior under variations in ambient temperature, initial temperature, coolant inlet temperature, cell heat generation, and Joule heating. However, it cannot capture coolant flow rate fluctuations, which are essential for liquid cooling start–stop conditions in energy storage containers. To address this, we use an enhanced LTI+HTC ROM, which incorporates flow-rate-dependent heat flux at the fluid–solid interface into the LTI ROM. This is achieved by establishing a correlation between the coolant flow rate and the interface heat transfer coefficient (HTC). We further improve model fidelity by applying interface heat flux distribution features extracted from CFD. Comparisons with 3D CFD results demonstrate that the LTI+HTC ROM is highly accurate and significantly reduces computational cost, making it a practical tool for thermal management studies under dynamic cooling conditions.