BMW leads the charge
BMW aims to be the first car maker to play unplugged in the electric vehicle arena. From mid-2018, the German brand will have a wireless charging option for its new 530e plug-in hybrid, eliminating the need to connect car and charge point with a cumbersome cable.
Other brands are developing wireless recharging technology but none of them have so far announced a firm launch date. BMW plans to introduce wireless charging first in Europe and the US but it will come to Australia.
“We have strongly indicated our interest in the technology and aim to offer it to the Australian market as soon as is practicable,” says BMW Group Australia chief Marc Werner.
“The BMW i and iPerformance brands are vital (to) ensuring we sit at the forefront of eMobility. Wireless charging is the next significant technological advancement.”
BMW presented a prototype wireless charger at the launch in Germany of the 530e.
A cable connects the power supply to a mat about 90cm long, 80cm wide and 6cm thick on the floor of a garage or a parking space. A smaller pad, 30cm square and only 2cm deep, is fixed under the car between the front wheels.
It works on the same inductive charging principle used in rechargeable toothbrushes and, more recently, Samsung smartphones. But BMW has both scaled up and toughened up the technology. The basic set-up can be used in other rechargeable BMW models.
Engineers have put both components through severe physical tests. The pads, made of aluminium and cased in plastic, survived. They were scratched but functional, says BMW wireless charging project manager Winfried Siegl.
There are also safety features such as the floor pad’s detector for living and foreign objects. If, say, a cat curls up on the floor pad while a car is charging, the current is cut.
Siegl says BMW and Daimler are working jointly to develop wireless charging tech. They’re normally the best of enemies, so collaboration means both believe wireless recharging is very, very important.
BMW’s version is very easy to use. Approaching the pad head-on, the central screen in the instrument panel displays an image from the car’s forwardfacing camera with two blue lines showing the correct path.
When the car is within a metre or so, the screen view switches to a graphic. The driver positions a green ball representing the car over a blue circle representing the charging mat. An animated graphic confirms charging has begun.
It’s more convenient than using a cable but there are disadvantages. Inductive charging isn’t as energy efficient as cable charging. There’s a loss of about 10 per cent, Siegl estimates. He expects the tech will cost more than BMW’s $1750-plus-installation cableconnected i Wallbox, though the wireless charger will refill the 530e’s lithium-ion battery almost as fast.