When Volvo displayed a crashed C30 electric in Detroit, no eyebrows should have been raised. After all, everything that matters is installed inside the passenger safety cell, which is a very strong structure in any modern car. And the inherent dangers of a lithium-ion battery are trivial compared with those associated with a tank full of petrol. In fact, if electric cars had been invented first, we suspect that petrol engines would be banned on safety grounds.
The car on show had a fully charged battery when it was tested at Volvo Cars’ crash test laboratory in early December 2010. The crash was an offset collision in which 40 per cent. of the front hit a barrier at 40mph. Both the batteries and the cables remained intact after the collision.
Volvo C30 Electric.
The structure and — generally — mass distribution of an electric car differ from those of a conventional car. The new components pose a number of new safety issues.
The Volvo C30 Electric has a quoted range of ‘up to’ 95 miles; the battery pack weighs about 280kg — roughly 30kg more than the pack used by Renault-Nissan, for example — and takes up far more space than a conventional fuel tank. Under the bonnet, the combustion engine has been replaced by a smaller and lighter electric motor. The car has a 400V high-voltage electrical system.
One challenge is to reinforce the crumple zone at the front, because the motor occupies less space than a piston-engine. The engine would normally act as a barrier in a severe collision, helping to distribute the collision forces. In the C30 Electric, this task is performed by a reinforced frontal structure that also helps absorb the increased collision energy created as a result of the car’s added weight; the C30 Electric is roughly 300kg heavier at the kerb than a standard C30.
In the Volvo C30 Electric, the batteries are fitted in the traditional fuel tank position and in the central tunnel. The battery-housings are necessarily robust. Beams and other parts of the car’s structure around the battery pack are reinforced; all the cables are shielded.
Volvo C30 Electric power management display can be distracting and baffling.
The crash sensor in the car controls the fuses. Power is cut in 50ms in a collision by the same signal that deploys the airbags.
The system has several fuses that cut directly if an earth fault is detected, such as a damaged cable coming into contact with the body frame.
Apart from the offset crash, the C30 Electric has been subjected to the same crash-testing régime as any Volvo. These include side collisions, rear-end impacts, and front and side collisions with a rigid pole.
Demo fleet for U.S.
Volvo Cars’ electric car project currently comprises about 250 vehicles that will be used by a number of companies and authorities. Deliveries of the first Volvo C30 Electric to customers in Sweden will start early next year, but a demo fleet is planned for the United States later in 2011.
The Volvo C30 Electric represents one leg in Volvo Cars’ electrification strategy. There are two others.
Volvo will introduce a plug-in hybrid in Europe in 2012. It features a diesel engine backing up the electrical motor. Emissions of less than 50g/km CO2 are promised. Later, the plug-in hybrid will go to the United States with a petrol engine instead of the diesel backing up the electrical drive.
Volvo C30 Electric power management display can also be straightforward and helpful.
The third leg of the strategy is to use power hybrids to give more miles to the gallon from Volvo's new, upcoming generation of downsized engines.