Volvo finds a way to turn body panels into batteries [w/video]

Thu, 17 Oct 2013

One of the problems with designing an electric vehicle is figuring out where to fit the battery pack. Volvo – as a part of a European Union research project – is working on a way around this issue by replacing standard parts with lightweight components that double as batteries on both conventional and plug-in vehicles. The image above shows one such piece on a Volvo S80. While looking like nothing more than a carbon fiber plenum cover, the piece is actually a battery pack that can store and supply enough energy for the car's entire 12-volt power system.

The parts are made by sandwiching super capacitors (which can charge faster than standard batteries) in between layers of carbon fiber. They can then be formed to replace numerous body panels such as the decklid, roof or door panels. Volvo says that the replacing the body panels and batteries with these nano batteries can help reduce the vehicle's weight by as much as 15 percent. It has taken more than three years just to design the batteries, so there's no telling when, or if, we'll ever see this technology used on a production vehicle. Scroll down for a video and press release on Volvo's innovative battery technology.

Volvo Car Group makes conventional batteries a thing of the past

Volvo Car Group has developed a revolutionary concept for lightweight structural energy storage components that could improve the energy usage of future electrified vehicles. The material, consisting of carbon fibres, nano structured batteries and super capacitors, offers lighter energy storage that requires less space in the car, cost effective structure options and is eco-friendly.

The project, funded as part of a European Union research project, included Imperial College London as the academic lead partner along with eight other major participants. Volvo was the only car manufacturer in the project. The project team identified a feasible solution to the heavy weight, large size and high costs associated with the batteries seen in hybrids and electric cars today, whilst maintaining the efficient capacity of power and performance. The research project took place over 3.5 years and is now realised in the form of car panels within a Volvo S80 experimental car.

The breakthrough
The answer was found in the combination of carbon fibres and a polymer resin, creating a very advanced nanomaterial, and structural super capacitors. The reinforced carbon fibres sandwich the new battery and are moulded and formed to fit around the car's frame, such as the door panels, the boot lid and wheel bowl, substantially saving on space. The carbon fibre laminate is first layered, shaped and then cured in an oven to set and harden. The super capacitors are integrated within the component skin. This material can then be used around the vehicle, replacing existing components, to store and charge energy.

The material is recharged and energised by the use of brake energy regeneration in the car or by plugging into a mains electrical grid. It then transfers the energy to the electric motor which is discharged as it is used around the car.

The breakthrough showed that this material not only charges and stores faster than conventional batteries can, but that it is also strong and pliant.

The results so far

Today, Volvo Car Group has evaluated the technology by creating two components for testing and development. These are a boot lid and a plenum cover, tested within the Volvo S80.

The boot lid is a functioning electrically powered storage component and has the potential to replace the standard batteries seen in today's cars. It is lighter than a standard boot lid, saving on both volume and weight.

The new plenum demonstrates that it can also replace both the rally bar, a strong structural piece that stabilises the car in the front, and the start-stop battery. This saves more than 50% in weight and is powerful enough to supply energy to the car's 12 Volt system

It is believed that the complete substitution of an electric car's existing components with the new material could cut the overall weight by more than 15%. This is not only cost effective but would also have improvements to the impact on the environment.

Volvo Car Group lead the way
Electrified cars play an important role in Volvo Car Group's future product portfolio and the company will continue to find and develop innovative and advanced technical solutions for the cars of tomorrow.

List of participants
Imperial College London ICL United Kingdom (project leader)
Swerea Sicomp AB, Sweden
Volvo Car Group, Sweden
Bundesanstalt für Materialforschung und-prüfung BAM, Germany
ETC Battery and FuelCells, Sweden
Inasco, Greece
Chalmers (Swedish Hybrid Centre), Sweden
Cytec Industries (prev UMECO/ACG), United Kingdom
Nanocyl, NCYL, Belgium

By Jeffrey N. Ross