Immersion Cooling Battery Technology Promises Improved EV Performance, Safety

XING Mobility, a leader in immersion cooling battery technology, has released its IMMERSIO Cell-to-Pack (CTP) EV battery pack with immersion cooling.

IMMERSIO Cell-to-Pack (CTP) EV battery pack. Image used courtesy of XING Mobility

 

Based on the company’s patented immersion cooling technology, the EV battery pack solution promises enhanced safety, higher battery energy density, and improved vehicle performance through its superior heat dissipation capabilities.  

XING’s immersion cooling technology has traditionally been targeted for industrial EV applications, like mining and construction, but the new CTP solution will extend the technology’s application space to include passenger EVs as well.    

 

Battery Thermal Management Key to EV Performance

Due to the high power densities of modern EV battery packs and their impact on vehicle safety and performance, thermal management of the battery system is a critical design criterion for e-OEMs.   

In addition to safety concerns like thermal runaway caused by cell shorts and overheating, effective heat removal and temperature management directly impact EV performance by improving battery charging speed and energy storage capacity. 

EV powertrain and battery. Image used courtesy of XING Mobility
 

Immersion Cooling for EV Batteries 

Heat can be removed from a battery or other system through conduction, convection, or radiation to prevent excessive temperatures that can damage equipment, reduce performance, or even create safety hazards (thermal runaway, etc.). 

 

Immersion cooling of individual battery cells. Image used courtesy of XING Mobility

 

The main methods of removing heat from an EV battery are air and liquid cooling, with indirect liquid cooling being the predominant solution (similar to radiator-based cooling systems in an internal combustion engine). These cooling methods typically require complex systems constructed with cooling channels, cold plates, and pipes to remove heat from the battery pack indirectly.

Immersion cooling operates deeper within the battery pack, integrating the cooling system at the individual cell level. XING uses advanced, high-nickel cathode, cylindrical lithium-ion cells cooled by mineral oil for its immersion cooling technology.

According to XING, a battery pack can be kept at a temperature 20 to 30 °C cooler with immersion cooling than with traditional indirect liquid cooling.  

 

Improved temperature management with immersion cooling. Image used courtesy of XING Mobility

 

Preventing Thermal Runaway

A key safety advantage of immersion cooling is preventing thermal runaway. For an EV, thermal runaway in the battery pack can be disastrous, resulting in extremely hot fires that are difficult to extinguish.  

Thermal runaway is initiated by the failure of an individual cell that shorts, overheats, and then breaches its housing, spreading flammable electrolytes across the entire battery.

By cooling and monitoring individual cells, immersion cooling systems can greatly reduce the risk of individual battery cell failures that lead to thermal runaway.    

   

Battery thermal runaway in an EV. Image used courtesy of Tapecon

 

IMMERSIO Cell-to-Pack (CTP) Solution for Passenger EVs

The new IMMERSIO CTP solution results from XING Mobility’s extensive research and development in, and experience commercializing, immersion cooling technologies.   

XING’s immersion cooling technology (IMMERSIO 25) was initially designed for industrial EVs, like mining and construction vehicles, due to the intense battery discharge levels and high heat generation common in these vehicle batteries. But with CTP, the tech is now migrating to a broader range of vehicles, including passenger vehicles like sedans, sports cars, trucks, and SUVs. 

For these EV applications, IMMERSIO CTP offers a high energy density of 200 Wh/kg and the ability to charge quickly from 20% to 80% SOC (state of charge) in just 15 minutes. The new battery pack can accommodate bus voltages up to 900 V.   

The unit incorporates extensive intelligence and monitoring, including a Cell Management Unit (CMU) and an Active Safety Module that monitors and controls individual cells' temperature, voltage, and current.

XING Mobility works with its customers to customize the IMMERSIO CTP platform to the specific needs of the EV make and model.