THE TECHNOLOGY BEHIND IMMERSIO™ MODULAR BATTERY SYSTEM: IMMERSION-COOLING
Battery cells are immersed into dielectric coolant which with the chrematistic of non-fired, non-toxic. Coolant is with the feature of “high heat removing capability” to mitigate the risk of thermal runaway within pack design configuration.
THE CHALLENGE FOR THERMAL CONTROL
A fast charge under low temperature could lead to lithium plating, and operating at high temperature could lead to the rapid build-up of solid-electrolyte interphase.
The conventional method of hybrid battery system cooling is air cooling via fans and air ducts. In contrast electric vehicle battery systems are typically liquid-cooled, with extensive coolant channels, cold plates, and coolant pipes in the interior of the battery system, supported by pumps, fans, coolant tanks, and radiators outside of the battery system. At low volume production, designing a manufacturable and safe liquid-cooled is challenging and costly.
The contact between coolant and the battery cells is still secondary, separated by a coolant jacket, electrical insulators, cold plates, or both.
ENHANCED SAFETY DESIGN FOR
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.
To design and build such an immersion-cooled battery system, one has to consider the flow channels within the battery modules for optimal coolant flow. To reduce the number of coolant piping, modules should be stacked together tightly, leaving a continuous flow channel for the coolant. The entire system should also be designed to be leak-tight and leak-tested.
Because the coolant is expected to contact the battery cells directly, this coolant has to be non-conductive, eliminating water and ethylene glycol from the choices for consideration. Hydrofluoroether has gained popularity in recent years as a substitute for ozone-depleting refrigerants such as CFCs and HFCS, It can also be used as a non-conductive coolant in immersion-cooled battery systems.
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.
An Innovative Method for Battery System Thermal Control
With an ever-increasing global demand for electric vehicles, demand for safer and longer-lasting electric vehicles and EV batteries is rising. Immersion cooling is an innovative method for battery system thermal control, opening up 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 towards off-highway vehicles' electrification, especially for low-volume, high-mix applications.
Pioneered in Immersion Cooling technology for EV, and patented world-wide.
Patent on immersion cooled battery module stacking design, with coolant flow design to achieve all cells immersed into the coolant.Patent in Taiwan, Japan, Korea, US, EU.
CUSTOM DEVELOPMENT SERVICE
With an ever-increasing global demand for electric vehicles, demand for safer and longer-lasting electric vehicles and EV batteries is rising. Immersion cooling is an innovative method for battery system thermal control, opening up 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 towards off-highway vehicles' electrification, especially for low-volume, high-mix applications.
XING Mobility provides engineering consulting services and technology collaborations for chemistry and oil enterprises; world leading engineering fluid leader Castrol under BP is one of them. XING Mobility has also initiated advance R&D projects with top global automotive companies for immersion cooling applications. In the meanwhile, XING Mobility offers custom development for battery systems to volume industrial and commercial vehicles. The partnership between HKS Power in Japan and XING Mobility facilitates XING Mobility to introduce immerison cooling product and service to Japan market.