Simulation Study on the Single-Phase Immersion Cooling Performance of Lithium-Ion Battery Packs

With the continuous development and innovation of thermal management technology for lithium-ion batteries, the advantages of direct immersion liquid cooling technology have become increasingly prominent. However, at present, there is relatively little research on immersion liquid cooling systems, an...

Full description

Bibliographic Details
Published in:Applied Sciences
Main Authors: Jiajun Hu, Bin Yu, Zhenshan Chen, Shuaikang Chen, Shuo Wang, Fengxiang Li
Format: Article
Language:English
Published: MDPI AG 2025-08-01
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/17/9531
Description
Summary:With the continuous development and innovation of thermal management technology for lithium-ion batteries, the advantages of direct immersion liquid cooling technology have become increasingly prominent. However, at present, there is relatively little research on immersion liquid cooling systems, and current research is still mainly focused on small-capacity battery systems. Therefore, taking a large-capacity battery pack as the research object, a new type of single-phase immersion liquid cooling system was designed. The battery pack has a charge and discharge rate of 1C, consists of 52 cells, and has a total capacity of 52.249 kWh. It was compared with traditional liquid cooling and static immersion liquid cooling. Then, the effects of the aperture of the flow distributor, the inlet flow rate of the cooling liquid, and the type of cooling liquid on the cooling performance of the dynamic immersion battery pack were discussed. The holes on the flow distribution plate are primarily designed to facilitate a relatively uniform distribution of incoming liquid flow. Our research found that compared with traditional liquid cooling and static immersion liquid cooling, the overall cooling performance of the dynamic immersion cooling system was significantly improved, with the maximum temperature <i>T</i><sub>max</sub> decreasing by 7.8 °C and 6.6 °C, the maximum temperature difference Δ<i>T</i><sub>max</sub> of the entire pack decreasing by 5.5 °C and 5.8 °C, and the maximum temperature difference U-DΔ<i>T</i><sub>max</sub> between the top and bottom surfaces of the battery pack decreasing by 10.1 °C and 8.96 °C. An appropriate aperture had a positive impact on the cooling effect of the battery pack, with the best effect at a aperture of 4 mm. <i>T</i><sub>max</sub> and Δ<i>T</i><sub>max</sub> gradually decreased with an increase in the flow rate of the cooling liquid, with <i>T</i><sub>max</sub> decreasing from 42.3 °C to 31 °C and Δ<i>T</i><sub>max</sub> decreasing from 14.8 °C to 7.9 °C, but the rate of the temperature decrease gradually decreased. Deionized water in the cooling liquid had the best cooling effect, while ethyl silicone oil had the worst cooling effect. The novel single-phase immersion cooling system developed in this study serves as a valuable reference for the design of immersion liquid cooling systems in large-capacity battery packs, contributing to enhanced temperature uniformity and improved system safety.
ISSN:2076-3417