Back in 2009 the electric car was nothing but a consumer fantasy. While car manufacturers were busy developing a range of battery powered models, the first widely available vehicles wouldn’t become available until at least a year or two later.
However, it was at the 2009 Frankfurt motor show that Audi showcased its vision for an electric car future in the form of the sleek e-tron concept. While that car is now six years old, its design and the thinking behind it has shaped electric cars as we’ve come to know them. Here we highlight the technology and design features showcased by the e-tron project that have transformed electric vehicles from sci-fi pipedream to retail reality.
The greatest difficulty with electric cars is producing a battery pack capable of storing sufficient charge for a usable range, but which is small enough to fit within a car. Traction batteries, as used in the earliest electric vehicles, were considered far too bulky, so Audi focused on lithium-ion technology – exactly the same tech that powers your phone and laptop. While research in the field has been conducted by experts around the world – with the specific aim of reducing weight and maximising capacity – Audi was amongst the first to utilise the tech for automotive purposes. And with great effect, too – the 2009 e-tron concept was capable of accelerating from 0-62mph in 4.8 seconds and going on to a top speed of 124mph.
Until battery technology advances further, electric cars suffer from a significant weight penalty over their combustion-engined counterparts, with models typically weighing in at around 200kg more. To offset this bulk Audi turned to its Space Frame technology, which sees core structures built from a cocktail of exotic metals to minimise weight without compromising on strength. This has been seen in a number of Audi road cars, though allied to the e-tron concept’s aluminium and carbon fibre body shell. This trend has now been seen on production vehicles, most notably BMW’s ‘i’ range, and will likely be used extensively on other cars as production costs are reduced.
The reason why you sit in your petrol car freezing for a minute or two as you wait for the cabin to warm up is because conventional vehicles use waste heat generated from the engine to provide a more agreeable temperature for their occupants. Electric motors do not generate sufficient heat to transfer to other areas of the car, and early models got around this with a supplementary electric heater. Anyone who heats their house with electricity will know that these aren’t terribly energy efficient though – the last thing you need in car with finite electricity reserves. Audi got around this problem by introducing a heat pump system to the e-tron – an automotive first – that converts mechanical work into heat energy – vastly reducing the energy burden on the batteries.
Brake energy recuperation
Scavenging the energy normally wasted through braking has been used in conventional vehicles as an efficiency boost, but the technology has really come into its own in electric cars. Showcased on the 2009 e-tron concept and used on all e-tron models since, the system converts the car’s kinetic forces into electrical energy, which is then fed back into the battery to maximise range. What’s more, they reduce wear on conventional brakes by slowing the vehicle as soon as the driver lifts off the throttle – meaning with practice, electric car drivers can anticipate stopping distances to maximise charging.
Truly independent four-wheel-drive
Free from the constraints of an internal combustion engine, Audi’s engineers bestowed the e-tron concept with a new type of four-wheel-drive system. By powering each wheel with its own individual electric motor, drive can be sent instantly to the wheel with the most traction, instantly raising the car’s performance in demanding situations. This layout also aids weight distribution – crucial for a high performance sports car.
Nothing increases the uptake of new technology like making it as convenient as possible for users. Wireless charging technology – used for years in small appliances such as electric toothbrushes, has been on the cards for electric vehicles for some time, with a number of manufacturers working on their own systems. So forward thinking was Audi with its e-tron concept though, that the bright red show car was fitted with inductive charging tech, meaning it need only be parked over a corresponding pad for the electricity to flow freely through the air. Technology company Qualcomm Halo has since been leading the charge in getting wireless charging tech fitted into the nation’s road infrastructure, so in the future electric vehicles can be topped up as they drive, eliminating the range anxiety and lengthy charging times currently experienced by electric vehicle owners.
Radical new shapes
Audi modelled the e-tron as a two-seater sports car to bring people around to the idea that an electric motoring future was something to get excited about. What it in fact showed was that without the need to keep an internal combustion cool, designers of electric cars could be a lot more free in their efforts, and create vehicles that moved away from the traditional layout of four front-facing seats and a boot behind.
Feeding into the perception that electric cars are ‘of the future’, the e-tron kicked off a new form of car-based communication. Dubbed ‘Car-to-X’, the system previewed a whole new era of connected car technology which would allow vehicles to communicate with both local information services and other cars, to get information about traffic, recharging stations and other useful motoring services. Unlike current Wifi enabled cars, the ‘X’ denotes communication with any other form of system, with Audi claiming the tech could benefit drivers by not only enhancing safety, but also convenience and efficiency, by feeding into every aspect of the car. Elements of this technology, including ‘traffic flow’, which uses data from traffic control infrastructure to modulate the car’s speed so you need never stop at a red traffic light, are currently in development, and are expected to be introduced into forthcoming generations of Audi vehicles.