In liquid immersion cooling of the EV battery, the battery cells are completely submerged in the dielectric heat-transfer fluid. This cooling method is called Single-phase Liquid Immersion Cooling (SLIC).
The dielectric coolant is typically circulated with a pump to ensure it flows continuously throughout the device architecture or circuits. It comes directly with all cell walls, tabs, and electrical wiring within the battery module.
The gadget consists of a radiator or heat exchanger to switch the heat power to the atmosphere. The direct liquid coolant absorbs the heat generated through the cells and direct conduction. It is then transferred to a heat switch.
If the heat volume is adequately low, battery module cell partitions can passively cool it. For this, it will use convective airflow. Full immersion of battery cells additionally guarantees the best thermal management and consistency.
A vital advantage of dielectric coolants over water-glycol and different conductive coolants is they may be delivered into direct contact with all components. It will do so without inflicting cell thermal runaway.
It also reduces electric failure or consumer shock accidents. Moreover, the protection and environmental issues related to leakage and disposal of risky aqueous glycol coolants are prevented with biodegradable, non-poisonous dielectric liquid coolants.
How Has Immersion Cooling Changed The EV Battery Application?
Immersion cooling has been effectively utilized in sectors such as data centers. However, a few companies have lately started using it for EV battery applications.
New technology for EV battery cooling tools, the use of dielectric fluid, has been introduced. 3M is a company that makes specialty or engineer-grade fluids for advanced thermal solutions for EVs
Why A lot of trials and RDs helped in the expansion of its understanding. At is the Future of Immersion Cooling Solutions
Immersion Cooling lets huge running situations be adequately served, such as excessive or low temperatures, extended altitudes, and tough areas.
Immersion cooling has already been tested in particular industries, such as data centers, subsea cables, and transformers. To start with, it was also considered an early frontrunner for EVs; however, this technique fell in the back because its chemical composition wasn’t accurate then, and the fluid used became too strong.
Although conventional methods of immersion cooling working principles and strategies can also be progressed and strengthened, the solution is to overcome the superfast charging feature and may also want a shift in our considering cooling. That’s why immersion cooling merits getting renewed attention. Companies like 3M have advanced specifically designed dielectric fluid for EV batteries.
Another strong attention for immersion cooling is its benefit on environmental impact. The dielectric fluid utilized in immersion cooling is a biodegradable and non-poisonous fluid that doesn’t diminish battery recycling.
Although the immersion cooling generation indicates the promise of technically first-rate overall performance, because of the accelerated weight and cost compared to presently used strategies, it is probably tough for immersion cooling to attain mass manufacturing within the EV enterprise.
Nevertheless, electric vehicle thermal protection policies are evolving, forcing the enterprise to search for those trade cooling technologies.
Immersion Cooling Working Principle And Its Other Elements
EV Batteries have precise running stages, which might be crucial for battery lifestyles and overall performance. They are designed to perform at ambient temperature, that’s between 68°F and 77°F (20°C and 25°C). Higher control over the battery temperature improves their overall performance and lifestyles.
1. During operation, they could face up to temperatures between -22°F and 140°F (-30°C and 50°C)
1. During recharges, they could face up to temperatures between 32°F and 122°F (zero°C and 50°C)
Batteries generate high heat at some stage, and their temperature should be delivered inside the running stages. At excessive temperatures (between 158°F and 212°F, or 70°C and 100°C), thermal runaways can happen, inflicting a series of response that destroys the battery pack.
During fast charges, batteries ought to be cooled down. This is because excessive current going into the battery produces extra heat that ought to be extracted to keep the fast charging and not overheat the battery, which can explode.
They are additionally required when the temperature is just too low or to reinforce performances. For example, cells can’t be charged below 32°F (zero°C). Or, EV companies provide battery preheating to attain excessive performances, going from zero to 60 mph in less than 2 seconds.
Thermal Management Challenges
The most common issues of advanced thermal solutions for EV batteries are leaks, corrosion, clogging, climate, and aging. As you may see, liquid cooling systems work in demanding situations inexistent for air cooling structures.
Battery modules, interconnections, pumps, and valves should all remain intact. Leaks can arise in liquid cooling structures, whose pipe connections have dangers of leaks because the battery ages. Any leaks will hastily degrade the battery’s performance and lifecycle. They may even cause the prevention of EV batteries from running at full capacity if humidity impacts the battery’s electric insulation.
1. Corrosion can arise in liquid cooling structures, whose cold plates can corrode because the liquid glycol gets older or past its lifecycle. Therefore, the cooling liquid ought to be replaced as a part of the maintenance program.
2. Clogging is a hazard due to the loads of small channels in which liquid travels within the battery.
3. Climates around the world pose special thermal demanding situations for batteries. Examples encompass leaving the automobile in high heat for a long time or residing in an area with extraordinarily low winter temperatures. Batteries should be capable of tolerating massive temperature levels in any respect. To attain this, the battery-cooling gadget should be energetic even if the automobile isn’t always in use.
4. Aging leads to thermal control issues that are deliberate for EVs. As batteries age, a bigger part of power is lost as heat. The thermal control gadget ought to be constructed for those more difficult situations that arise later inside the battery lifecycle, no longer only for ordinary situations at some stage in the preceding years.
If you look around, numerous companies may provide you with cooling solutions; however, it is not sure if the advanced thermal solutions for EVs are perfect or not. After long research, trials, and errors, we have found that the immersion cooling working principle can help remove heat from electric vehicles’ circuits.
It has now become an integral part of the thermal management of electric vehicle battery systems. Apart from EVs, it is used in other industries, such as data centers, avionics, and hydraulics.