Immersion cooling for lithium-ion batteries – A review

• Published in: Journal of power sources Vol. 525; p. 231094
• Main Authors: Roe, Charlotte, Feng, Xuning, White, Gavin, Li, Ruihe, Wang, Huaibin, Rui, Xinyu, Li, Cheng, Zhang, Feng, Null, Volker, Parkes, Michael, Patel, Yatish, Wang, Yan, Wang, Hewu, Ouyang, Minggao, Offer, Gregory, Wu, Billy
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.03.2022
• Subjects: Degradation; Immersion cooling; Lithium-ion batteries; Thermal management; Lithium-ion batteries; Degradation; Thermal management; Immersion cooling
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2022.231094

Battery thermal management systems are critical for high performance electric vehicles, where the ability to remove heat and homogenise temperature distributions in single cells and packs are key considerations. Immersion cooling, which submerges the battery in a dielectric fluid, has the potential of increasing the rate of heat transfer by 10,000 times relative to passive air cooling. In 2-phase systems, this performance increase is achieved through the latent heat of evaporation of the liquid-to-gas phase transition and the resulting turbulent 2-phase fluid flow. However, 2-phase systems require additional system complexity, and single-phase direct contact immersion cooling can still offer up to 1,000 times improvements in heat transfer over air cooled systems. Fluids which have been considered include: hydrofluoroethers, mineral oils, esters and water-glycol mixtures. This review therefore presents the current state-of-the-art in immersion cooling of lithium-ion batteries, discussing the performance implications of immersion cooling but also identifying gaps in the literature which include a lack of studies considering the lifetime, fluid stability, material compatibility, understanding around sustainability and use of immersion for battery safety. Insights from this review will therefore help researchers and developers, from academia and industry, towards creating higher power, safer and more durable electric vehicles. [Display omitted] •Performance of battery immersion cooling and different cooling fluids reviewed.•Immersion fluids can increase heat transfer by up to 10,000 times compared to air.•Thermal properties of lithium-ion batteries and heat transfer mechanisms explored.•Safety implications of battery immersion cooling discussed.•Research gaps in battery immersion cooling presented.