Innovative Compact Thermal Management for High-Density Lithium-Ion Batteries: A Hybrid Cooling Solution

Abstract

Efficient heat dissipation technology for high heat flux density in compact energy storage battery packs is crucial for future development and currently represents a major bottleneck in technological advancement. To address this issue, this study proposes an innovative thermal management strategy: a compact hybrid air-cooling and liquid-cooling system designed to optimize the thermal efficiency of lithium-ion battery modules. The research methodology included the development of a physical model for the battery thermal management system (BTMS), complemented by experimental validation and grid independence checks to ensure the precision of the simulation outcomes. A controlled variable technique was applied to thoroughly examine the effects of five pivotal parameters on BTMS efficacy: the height of the liquid cooling tubes, the angle of contact between the tubes and the batteries, the velocity of the cooling liquid at the inlet, and the temperature of the cooling water. To simplify the analytical process and enable swift optimization, the study innovatively incorporated orthogonal experimental design, genetic aggregation, and the rank sum ratio (RSR) method, thereby circumventing the need for extensive CFD predictive computations. The optimal system configuration, as determined by these techniques, realized a peak surface temperature of 26.6 °C, a temperature gradient of 3.5 °C, a total energy expenditure of 52486 J, and a system mass of 0.099 kg under specific conditions: a 0 mm elevation difference between the cooling tubes and batteries, a 60° contact angle, a cooling liquid flow rate of 0.93 m/s, and a cooling water temperature of 22.5 °C. The results of this study confirm that the proposed hybrid cooling system markedly improves the thermal performance of lithium-ion battery modules, providing a practical solution for high-power applications.

Keywords: Thermal Management, Lithium-ion batteries, Computational Fluid Dynamics (CFD), Hybrid Cooling System, Optimization Design