Can the Vision lower the future charging time of electric cars at the 24 Hours of Le Mans?

InMotion, the catalyst for electric refuelling in e-mobility

Since 2012, different groups of students from Eindhoven University of Technology and Fontys University of Applied Sciences has been working on the development of electric racing cars. Their aim? To be the first to take part in the 24 Hours of Le Mans in 2023 in a fully electric racing car! It’s a race that demands a lot from the cars. But as Sjoerd Filmer explains, the ultimate goal is actually much more important – to develop new technology to charge batteries much more quickly – electric refuelling. 

Is charging time a major obstacle to the broader market success of e-mobility?

‘We think so, yes. There are of course other factors that dictate the success of e-mobility. Cars need to be more efficient and lighter in weight so that they consume less energy. But the charging infrastructure and energy producers must be ready for the huge uptake in electric vehicles.’

Have you developed and built the entire car and the infrastructure that goes with it yourselves?

‘We built our first electric car, the Fusion – based on the F3 cars, ourselves with the support of a number of partners, and went on to set several lap records with it. But we quickly realized that if you want to take part in races, you need to be able to charge at speed. So for the past eighteen months, we’ve switched our focus to the battery pack, the driveline, and the system design. The car itself has been built by a producer of racing cars. To participate in a real race, like the 24 Hours of Le Mans, the car needs be able to pass a range of tests, like the crash test, to make sure that it is safe for the driver.’

What is the biggest technical challenge posed by electric refuelling that you face?

‘Using cooling to reduce the heat that develops while driving at speed and charging. We’re looking very closely at developing the battery pack to make charging faster and easier by using a smarter method of cooling. Our way of cooling also results in less degradation of the batteries as well as greater energy density in the batteries as our method needs less space for the cooling system.’

What is the key principle behind your cooling method?

‘Battery cells comprise various layers, some of which are good insulators. The majority of cooling systems cool on the outside of the battery cells, leading to a difference in temperature between the outside and the core of the cell. A major difference in these temperatures accelerates degradation of the batteries. We have identified an efficient way of lowering the difference in temperature between the outside and the core of the individual battery cells considerably.’

How does you technology differ from that of a standard electric car?

‘We’re working with an 800 V system. The higher the voltage, the less current you need and the lower the heat development. This system is not yet widely used for passenger cars, so it’s difficult to locate small and lightweight components to make our car even lighter. But the 800 V system will be a great system for the future for use in all manner of passenger cars and SUVs.’

Can you charge more quickly with the 800 V system than with the new e-Porsche that uses the same system?

‘We haven’t tested it yet, but our car has been designed to charge 350 kW very soon, which is 80 kW more than the maximum achieved by the Porsche.’

Does this technology need a different charging infrastructure?

‘We use standard CCS connectors for charging, but also water-cooled hoses and connectors. Our charging speeds demand different infrastructure of course – the last thing that we want is the power to fail around Le Mans while we’re charging. We can call upon the expertise of Omexom if we have any questions about the charging infrastructure.’

Can you be more innovative than the industry as a whole in this area?

‘We’re just a small group of students in a vast industry. We don’t have the opportunities available to develop wholly new concepts for battery cells. But when it comes to fast charging, I think we have the capacity to revolutionise – as a not for profit organization, we can trial new concepts very quickly. If we have a new idea, we can start work on it right away, without having to worry about the direct impact on the financial result.’

And will you be driving the Vision at Le Mans in 2023?

‘Sadly not. I’d have loved to, but we decided to go for professional drivers. We don’t want to throw away years of work because of a steering error!’