Periodic Reporting for period 2 - I-BAT (Immersed-cooling Concepts for Electric Vehicle Battery Packs using Viscoelastic Heat Transfer Liquids (I-BAT))
Reporting period: 2021-10-01 to 2023-03-31
This research project is aimed to develop a novel methodology for the efficient cooling of electric batteries in the automotive field. The research activities are structured on three technical objectives and one management objective.
Technical objectives:
• To synthesize novel heat transfer fluids at the molecular and nanoscale level having optimal rheological and thermal properties. The goal is to maximize their thermal and flow performance.
• Fabrication and assembly of linear vortex generators to decisively improve the cooling efficiency by generating specific flow patterns in the cooling system.
• Apply the flow motion concepts in a novel BTMS and develop test fluids in terms of cooling efficiency.
Further objective:
• Management of the project and dissemination of the research findings to academia and industry.
Synthetization of heat transfer (HR) fluids relies on specific estimations provided by various numerical models, which in turn account for the contribution of viscoelastic stresses (i.e. by Phan-Thien-Tanner models) and shear-thinning effects (i.e. through Carreau-Yasuda Modelling approaches). These numerical models should be validated by an experimental dataset related to the rheological and thermal characteristics of the fluids.
Technical objectives:
• To synthesize novel heat transfer fluids at the molecular and nanoscale level having optimal rheological and thermal properties. The goal is to maximize their thermal and flow performance.
• Fabrication and assembly of linear vortex generators to decisively improve the cooling efficiency by generating specific flow patterns in the cooling system.
• Apply the flow motion concepts in a novel BTMS and develop test fluids in terms of cooling efficiency.
Further objective:
• Management of the project and dissemination of the research findings to academia and industry.
Synthetization of heat transfer (HR) fluids relies on specific estimations provided by various numerical models, which in turn account for the contribution of viscoelastic stresses (i.e. by Phan-Thien-Tanner models) and shear-thinning effects (i.e. through Carreau-Yasuda Modelling approaches). These numerical models should be validated by an experimental dataset related to the rheological and thermal characteristics of the fluids.
The major achievements in the project during the considered period are
• The baseline fluids are determined. Potential polymers are selected.
• Setup for benchmark tests is developed and pre-tested.
• Some HR fluids with and without additives were sent to FAU and evaluated optically on the PIV setup.
• Preliminary vortex generators were designed. The experimental setup for the evaluation of these structures is prepared.
• Simulation setup
• Battery-Cell-Simulation
• Molecule dynamics simulation setup
• Cells for battery prototype were selected. Two prismatic cells were selected for the BTMS prototype planned in WP3. The battery cells are tested and thermally evaluated.
All important project activities are performed in line with the original plan.
• The baseline fluids are determined. Potential polymers are selected.
• Setup for benchmark tests is developed and pre-tested.
• Some HR fluids with and without additives were sent to FAU and evaluated optically on the PIV setup.
• Preliminary vortex generators were designed. The experimental setup for the evaluation of these structures is prepared.
• Simulation setup
• Battery-Cell-Simulation
• Molecule dynamics simulation setup
• Cells for battery prototype were selected. Two prismatic cells were selected for the BTMS prototype planned in WP3. The battery cells are tested and thermally evaluated.
All important project activities are performed in line with the original plan.
An immersion cooling concept for batteries based on non-Newtonian fluids and vortex-enhancing engineered cell surfaces has not yet been developed. With this project, we are well on our way to achieving this goal. In this first year of the project, we have set up our toolchain to find the best possible fluid properties and surface geometries to achieve immersion-cooled battery modules of compact size with extremely low pumping losses. If we achieve our goals, this will lead to small batteries for plug-in hybrid vehicles or full battery electric vehicles, increase battery life enormously and thus have a positive impact on the sustainable management of our planet's resources.