Exploring the Benefits of Immersion Cooling
Immersion cooling for lithium-ion batteries
Immersion fluids can increase heat transfer by up to 10,000 times compared to air.
Immersion Cooling can make battery systems virtually non-flammable
Plus or Minus 1 degree C of uniformity can easily be achieved at a 2C rate for NMC pouch type cell
SImplifies systems by removing HVAC unit, Chiller, Fire System, Door Switch, Leak Detection, Exhausting fans and Duct work.
Heat from Battery can be more easily captured and used for building mechanical systems
Battery thermal management systems are critical for high-performance electric vehicles, where the ability to remove heat and homogenize temperature distributions in single cells and packs are key considerations. Immersion cooling, which submerges the battery in a dielectric fluid, has the potential to increase 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 that 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 to create higher power, safer, and more durable electric vehicles.
