Inductive charging vital, says Audi

Plug-in hybrids and full battery-electric cars will never reach their potential until wireless inductive charging spreads across the fleet, Audi’s technical boss reiterated recently.

Confirming Audi will have an inductive charge option for the diesel-electric Q7 e-tron TDI, Audi’s development chief, Dr Ulrich Hackenberg, insisted car-makers had an obligation to make it easier for people to charge electric vehicles.

Otherwise, he said, people will get bored and fed up with handling heavy, sometimes dirty and tamper-prone electrical cables up to four times a day and revert to pure internal-combustion power, causing even greater CO2 emissions.

“Inductive charging is a comfort and that’s the key to it even if it’s slightly less efficient right now,” Dr Hackenberg explained.

“It’s not so comfortable today to take a cable and plug it in and out repeatedly for some people.

“In my own garage I sometimes have to go around the car with the cable or over the car or around the tools in the shed to get to the plug-in point, so I know why we have to hurry with inductive charging.”

Automotive induction charging systems are already available in the aftermarket including for heavy commercial use and Audi has already previewed its version in the TT Offroad concept.

There are currently two methods of inductive charging racing to gain the ascendency in charging electric and plug-in hybrid cars.

One is a plate fixed to a garage floor and the other uses a similar method, but automatically lifts the plate closer to the underside of the car to increase the charging efficiency, reduce wastage and shrink charging times.

“There are different systems but we are working with the lift-type system and we are very close to production with it,” he said.

“It will be available in the Q7 e-tron TDI as an option and the convenient part is that whenever the car is parked in your garage, it’s effectively plugged in. And we’re not far from the time when the car will park itself so it is perfectly aligned with the induction plate.

“Our system will start with 3.6kW of charging and it will go to 7.2kW soon, and there are ideas to go higher.”

That will make life easier for anybody who buys Audi's biggest hybrid, the Q7 e-tron TDI, which made its debut at the Geneva motor show in March this year.

The big new German luxury SUV will arrive in European and Australian showrooms later this year, followed in 2016 by the ground-breaking e-tron TSI version that promises 56km of pure-electric range and 0-100km/h sprint in just six seconds.

The plug-in Q7 delivers the astonishing fuel economy figure of just 1.7L/100km on the NEDC combined cycle, even though it has a combined output of 275kW of power and 700Nm of torque from its electric and diesel motors.

It can carry 17.3kWh of energy with it in its 168 lithium-ion battery cells and a two-phase charging system can have it topped up from flat in two-and-a-half hours.

But Dr Hackenberg admitted there are downsides to the convenience of inductive charging systems, which is based ont he same technology now available for mobile devices -- including in the new Q7.

One impediment is that it can’t match a wallbox and cable for fast-charging, and the other is the sheer cost of it – with Hackenberg admitting Audi hasn’t quite figured out how much of that cost to pass on to customers.

“With this technology it is not possible to fast-charge and it’s more expensive. If you only have 10 minutes in the garage to charge, you can’t do it,” he said.

“It is not cheap. We have the cost of the components and there is a lot of material and it depends if your garage is built or you are building it and it depends on if you want it on the floor or built flat into the floor.

“The costs to us are more than 1000 euros and the price to you will depend on the volume, on how many people want it,” he explained.

The new Q7 completed its “Last Approval Drive” in Namibia earlier this month, when Dr Hackenberg and his development team applied last-minute fine-tuning to its second-generation large SUV, which sheds up to 325kg and is up to 28 per cent more efficient thanks in part to the debut of Audi's second-generation modular longitudinal platform.