Integrated liquid cooling for electric vehicles

Purpose and goal

The project´s goal was to investigate the possibilities for dielectric battery cooling systems and EHD pumping, including design and simulation work. Volvo will be an external user/client and evaluate the technology. In addition to discussions with Volvo, we have also established contact with key personnel within NEVS, Scania and Northvolt. Especially Northvolt has been assisting with information and expressed extra strong interest in this technology. A conceptual design with a simulation model, based on acquired requirement specification, has been developed

Expected results and effects

A concept design for APRtec cooling solution of the battery cells with dielectric fluid is made. This design offers a very high or maximum packing density for the battery cells because no pipes or cold-plates are used, as with water / glycol cooling. The simulation results show that the concept design supports fast loading up to 5C with a total liquid mass of less than 5% of the mass of the battery cells. Unlike water / glycol, no pipes or cold-plates are required and the total mass will be very attractive.

Planned approach and implementation

The plan was to obtain user requirements and information from Volvo. But it was extended to include NEVS, Scania and Northvolt. The actors were open to some extent but limited by confidentiality agreements with subcontractors. They are highly focused on the safety of the battery systems. This has a much greater importance than a thermal design. Further development work must focus on cooling system design to meet the safety requirements imposed on battery systems in electric vehicles. The requirement package is relatively complex.