It seems ironic, shortly after we published our essay on the most innovative car companies in the world, that Volvo announce something truly mind-blowing – lightweight structural bodywork which doubles up as a replacement for a car’s batteries.
The new material consisting of carbon fibres, nano structured batteries and super capacitors, is lighter than a conventional panel and yet stores energy faster than conventional batteries.
The material has been discovered as part of an EU-funded project including Volvo Car Group and nine other participants. The project was tasked with finding a viable alternative to the large size, heavy weight and high costs associated with the batteries used in today’s hybrid and electric vehicles while maintaining the same capacity and efficiency of energy performance.
The car used was a Volvo S80 which received a modified boot lid and a plenum cover made from the nanomaterial. The material is made from carbon fibres and a polymer resin, together with structural super capacitors. The reinforced carbon fibres sandwich the new battery and are moulded to replace the car’s steel body panels used in the car’s frame, such as the roof, door panels, bonnet and floor.
Volvo estimate that a complete vehicle made from this nanomaterial could be up to 15% lighter than a conventional electric car, with potential for cutting weight still further.
The super capacitors are integrated within the component skin and then recharged and energised by either harvesting energy under braking or by plugging the car into a mains electrical grid. It then transfers the energy to the electric motor, which is discharged as it is used by the car.
In the development S80, Volvo have used the boot lid to function as a conventional car battery – being lighter than the standard car’s boot lid and saving on both volume and weight.
The new plenum replaces both the rally bar, a strong structural piece that stabilises the car in the front, and the start-stop battery. In such an installation it saves more than 50% in weight and is powerful enough to supply energy to the car’s 12 Volt system (for powering on-board systems).
It’s a fascinating breakthrough, and one which we might well see in future cars. Volvo was the only car manufacturer in the project which has thus far run for 3.5 years.