Immersion Cooling
The Key to Safe, Efficient & Sustainable Energy Storage
Managing heat has always been the most difficult challenge of efficient and safe battery systems for Electric Vehicles and Energy Storage Systems. Overheating batteries causes device failure, reduced efficiency and operational lifetime, as well as a fire risk in event of Thermal Runaway. Vehicle makers and suppliers go to great lengths to develop thermal management that is efficient, reliable, and safe; the most common method is Indirect Liquid Cooling, which is fairly efficient, yet highly complex and expensive to manufacture.
Immersion cooling is an innovative method for battery system thermal control, opening new frontiers for thermal runaway prevention and battery cycle life, increasing the battery system's environmental adaptability. In addition to enhancing the optimal performance and safety of electric passenger vehicles, immersion cooling also presents a new pathway toward off-highway vehicles' electrification, especially for low-volume, high-mix applications. XING Mobility has advanced innovation and patents regarding immersion cooling technology. XING's engineering team provides custom development and integration of battery systems, and collaboration on intellectual property, empowering customers through immersion cooling solutions.
A Highly Effective Method for Battery System Thermal Control
The proper design considerations for immersion-cooled battery systems are different yet more straightforward than conventional liquid-cooled battery systems. Essentially, an immersion-cooled battery system integrates the cooling system into the battery housing itself, without extensive coolant channels, cold plates, and coolant pipes. Pressure relief features are now part of the battery housing, rather than only a cooling system feature. However, it does mean that the battery housing needs to be leak-tight, as any moisture or air would compromise the coolant’s ability to conduct heat away or flow to the battery cells and to flow through the system.
Cooling Performance
Immersion-cooled battery packs maintain 20 ~ 30% cooler temperature compared to conventional indirect liquid-cooled battery packs.
Thermal Performance test results shows 10-degree delta between immersion cooling and indirect liquid cooling method on cell surface temperature and 20-degree delta on busbar temperature represent the thermal control capability using immersion cooling solution. Immersion-cooled battery pack will have 20 ~ 30% cooler temperature compared to indirect liquid cooled battery pack.
What is thermal runaway?
When a single cell fails, the material within starts an exothermic (energy-releasing) decomposition reaction, and the rate of decomposition is positively correlated with temperature. In short, as temperature increases, decomposition occurs, further increasing the temperature, which causes further decomposition. This forms a feedback loop that goes on until the temperature reaches a point to rupture the cell and the remaining energy within the cell is released in the form of heat and pressure.
How does Immersion cooling help to suppress?
One of the main reasons to design and implement immersion cooling solutions into battery systems is to mitigate thermal runaway within one single cell. The reason behind fire and explosion on battery system is thermal runaway happen on a single cell and causes chain reaction to spread to multiple cells to increase to extremely high temperature and light up everything. When the heat dissipation is big enough to control thermal runaway within one battery cell, there is no chance for chain reaction from happening.
Nail Penetration Test Results
No fire propagation was detected when during nail penetration to a single cell, causing it to undergo thermal runaway. Surrounding cells’ surface temperature were recorded 20% below cell crashing temperature of 120ºC. Surfaced temperature on penetrated cell returned to normal working level in 10 seconds, while surrounding cells temperature returned to normal level within 15 seconds.
Active Thermal Runaway Suppression
Longer Cycle Life
Immersion cooled battery modules tested 10% longer life cycle compared to conventional indirect liquid cooled module at -4C/+2C charge/discharge rates. Immersion cooled battery module is capable of reaching over 6,000 charge-cycles with 70% SOH remaining.
Better Battery Warm-Ups
In extreme weather conditions, low temperature for instance, battery cells need to be brought up to working temperature to properly and safely function. XING’s immersion-cooled battery system shows an outstanding performance of 2X faster heat-up rate compared to indirect liquid cooling.
Contact
Let XING Mobility work with you for the new mobility and the sustainable future. Contact our Business Development Team right away.
Email
sales@xingmobility.com
Phone
+886 (0)2-2795-1279