The race is on if you’re an electric car maker to bring inductive charging to the market – in essence a method of charging an electric car without need for lengthy cables or plugging the car into a charging station.
The benefit is obvious – in the near to medium-term, electric cars are best suited to city and densely-populated urban dwellers, who typically own a home without a garage and who are unable to park nearby.
One of the first examples we saw in the UK was Oxford-based Liberty Electric Cars, who demonstrated their wireless charging solution in 2010. It’s been in development ever since, with car makers BMW, Daimler, Volkswagen and others involved in rival programmes being trialled in Germany.
Electronics company Qualcomm, who’ve been working with Drayson Racing and other teams in the FIA Formula E series, are convinced that plug-in charging is too cumbersome and that wireless charging is essential before there can be mass adoption of electric vehicles.
As part of a consortium of companies including Bombardier Transportation and the coachbuilder Van Hool, a research project used a Volvo C30 Electric with a power output of 89 kW (118 bhp) to develop a wireless solution using inductive charging.
The project was partly funded by the Flemish government and was initiated by Flanders’ Drive – a knowledge centre for the automotive industry in the Flanders region in Belgium.
Progress has been swift, however bringing the technology to market has been hampered by a lack of common standards in how such charging platforms should operate.
Qualcomm are trialling a solution whereby road lanes could be fitted with the technology charging vehicles as they stop at traffic lights or visit tolls on private motorways. Others see that as fanciful and overly complex, believing that pads installed in car parks or shopping centres would make more sense.
There’s nothing new about induction charging itself, it’s been used for many years for devices such as mobile phones and electric toothbrushes, but it’s inherently less power-efficient in transferring energy between two devices due to it using an electromagnetic field.
“Inductive charging has great potential. Cordless technology is a comfortable and effective way to conveniently transfer energy. The study also indicates that it is safe,” says Lennart Stegland, VP of electric propulsion systems at Volvo.
“There is not yet any common standard for inductive charging. We will continue our research and evaluate the feasibility of the technology in our hybrid and electric car projects.”
“The tests demonstrated that our Volvo C30 Electric can be fully charged without a power cable in about two and a half hours. In parallel with this, we have also conducted research into slow and regular charging together with Inverto, which was also a partner in the project,” added Stegland.
The way it works is an induction coil creates an alternating electromagnetic field from a charging base station. A second induction coil in the car picks up power from the electromagnetic field and converts it back into electrical energy that charges the battery.
“With inductive charging, you simply position the car over a charging device and charging starts automatically,” says Stegland. “We believe that this is one of the factors that can increase the customer’s acceptance of electrified vehicles.”