VW, Continental autonomous charging solutions point to more user-friendly EV future

As the automotive industry moves toward advanced levels of autonomous functionality, including self-parking capabilities, automakers such as Volkswagen Group and Tier 1 suppliers such as Continental are working to develop solutions that recharge EVs automatically after they are parked.

Continental Engineering Services is working on a fully automatic charging robot with Austrian startup Volterio, which developed the concept.

Aimed for use in private garages, the robots could also be deployed in public areas later, with volume production of the system planned for 2024 in Germany.

The solution is comprised of two components: the connector unit installed in the underbody of the vehicle and autonomous mobile unit on the floor.

After the car is parked, the two components connect automatically via a smart system, which could be controlled via ultra-broadband -- a radio-based communication technology for short-range data transmission.

Thanks to this system, the car does not have to be parked with extreme accuracy—the charging robot can correct from a deviation within 30 cm (12 inches).

Alex Rupprecht, director of driveline and electrification at the unit of German megasupplier Continental, said CES conducted an analysis of different recharging technologies.

Light and no ‘air gap’

In the end, a conductive solution was chosen for its lightness -- an inductive charging component would weight 25 kg compared with CES’ solution, which weights 2 kg -- as well as the elimination of an air gap, which lowers the charging efficiency of inductive and wireless charging solutions.

“There are other companies looking at similar solutions and with different approaches. We have also seen robot applications that connect from the side,” he said. “We investigated all these ideas and solutions, and from our point of view, the Volterio solution seems to be the most practical.”

Rupprecht declined to name specific automakers but said there is a letter of intent from at least one and said once the solution reached a certain market share, CES could open talks with energy companies or charging equipment companies as well.

One of the main technical challenges was designing the connectors on both the vehicle and ground units in a way that they were protected from any kind of dirt.

“On the car itself, just by driving it the connector could get dirty, especially during winter with salt spray and things like that,” Rupprecht said. “So, we have to protect the device on the car, and it's the same issue for the ground unit, even if it is just in your garage.”

The solution was to develop covers for both connection units that retract at the last possible moment before joining up.

“Our objective is to develop another solution that we can use in public parking as well, and another version later on which can be used for commercial vehicles where we then can transfer a higher amount of energy,” Rupprecht added.

Other approaches remain visionary

Volkswagen Group Components has also been working on a mobile charging robot, which at this point remains more of a conceptual vision than a workable product but could also find use in parking garages or restricted parking areas.

A VGC spokesperson confirmed the charging robot is still a prototype -- a press release from December 2020 noted one of the prerequisites for market maturity is Car-to-X communication to facilitate 'utonomous charging process.

“A ubiquitous charging infrastructure is and remains a key factor in the success of electric mobility,” VGC CEO Thomas Schmall said in the release. “Our charging robot is just one of several approaches but is undoubtedly one of the most visionary.”

Tim Urquhart, a principal automotive analyst at IHS Markit, said the development of such a device could be especially useful for EV owners who have space at home but may live far from public charging stations.

“One of my problems is there doesn’t seem to be much joined-up thinking between automakers and other players as to how they will get their vehicles charged,” he said. “This could also work in urban car parks and in urban environments, so there is a huge amount of potential, but commercialization and scale are the sticking points.”

That means automakers will have to buy into the concept and accept the extra cost in installing the charging component.

“That’s something they will have to negotiate, and this will probably start with premium brands before working its way down to more mass market vehicles,” Urquhart said. “It looks like [CES’ device] is a more cost-effective solution than the VW concept at least.”

He called VW’s idea a potential longer term solution for AVs entering self-parking facilities, where presumably the docking station will be able to connect to the vehicle.

“Then you will wind up with problem-free charging, which is what we all want,” he said. “For now, this is a really good step forward for vehicle electrification.”

Avoiding incompatibility

With CES making its plan public, the company has set itself up as an early mover in the nascent segment, however, Urquhart said it must prove the concept can work in all different types of environments.

“We need to see how it scales and how it practically works on a wide scale in a variety of contexts,” he said. “I can see automakers joining on board once they see it works. Customers can probably see the value in not having to lug around big heavy, dirty cables. This has the potential to help speed up electrification.”  

Urquhart added that it’s “entirely possible” that other big Tier 1s such as Robert Bosch might also see an opportunity here. The key will be avoiding having too much choice, he said.

“What’s required is that we don’t have four or five solutions where incompatibility becomes an issue,” he said. “The universality of this is absolutely critical, especially with connectors and the way it all works together.”