Researchers from Chalmers University of Technology have come up with a new battery concept. It contains carbon fiber that serves simultaneously as a load-bearing material, conductor and electrode. They call it “massless”, because the battery is part of the structure of whatever vehicle it powers, therefore canceling out its weight.
This new battery is the culmination of years of research, and this particular battery performs 10 times better than all their previous versions. It still only has 20% of the capacity for power per kilogram of mass (24 Wh/kg) compared to current lithium-ion batteries available, With the ability to work as a structural part of the vehicle, it can reduce the overall weight of the vehicle, since the battery is a significantly heavy part of any electric vehicle, be it a bicycle, car or even an airplane. Yes, an electric airplane.
“Previous attempts to make structural batteries have resulted in cells with either good mechanical properties, or good electrical properties. But here, using carbon fiber, we have succeeded in designing a structural battery with both competitive energy storage capacity and rigidity,” explains Leif Asp, Professor at Chalmers and leader of the project.
Currently, the battery materials have a stiffness of 25 GPa (Gigapascals), but they’re working on getting it to its potential of 75GPa. That effort has been financed by the Swedish National Space Agency. The aluminum foil will be replaced with carbon fiber as a load-bearing material in the positive electrode, providing both increased stiffness and energy density. The fiberglass separator will be replaced with an ultra-thin variant, which will give a much greater effect – as well as faster charging cycles. The new project is expected to be completed within two years.
The expectation is that the battery capacity could also be increased to nearly 75Wh/kg, bring it closer to the capacity of today’s lithium-ion batteries,
“The next generation structural battery has fantastic potential. If you look at consumer technology, it could be quite possible within a few years to manufacture smartphones, laptops or electric bicycles that weigh half as much as today and are much more compact,” says Leif Asp.
And in the longer term, it is absolutely conceivable that electric cars, electric planes and satellites will be designed with and powered by structural batteries.
“We are really only limited by our imaginations here. We have received a lot of attention from many different types of companies in connection with the publication of our scientific articles in the field. There is understandably a great amount of interest in these lightweight, multifunctional materials,” says Leif Asp.