Inductive charging could improve efficiency and performance levels for electric vehicles

Electric vehicles: inductive charging extends the range

Range anxiety: the idea of running out of battery power in the middle of a journey is something that haunts electric vehicle (EV) owners and is regularly cited as a reason why sales figures for EVs remain fairly low.

Inductive charging, replenishing electric battery power wirelessly, is an idea that could completely wipe out concerns about range anxiety and improve efficiency and performance levels for electric vehicles.

The technology, or at least the theory behind it, is relatively old. “You’re looking back at Maxwell’s equations of electromagnetism; it’s really fundamental physics,” explained physicist Laurie Winkless. “It’s about the connection between electricity and magnetism and [how you] can switch one with the other and you can use that in some ways. It’s quite old, in theory anyway, [but] doing it practically is quite new.”

The idea has been taken up by technology giants around the world. Smartphones and electric toothbrushes can be charged by simply placing them on a charging pad, but for EVs, inductive charging built into roads could be even more useful.

Qualcomm, the wireless telecommunications provider, has put the inductive charging theory into a practical solution for charging EVs with its Halo charging pads. But it wants to take the solution further: by putting the Halo plates into the road and charging EVs on the move. “The vision of the technology and our ultimate goal is the idea that you have a charging lane on motorway,” said Graeme Davison, vice president of technology at Qualcomm.

“You pull into that charging lane with your car and you get off 200 miles later with exactly the same amount of charge, if not more perhaps, than you pulled on and you’ve got no range anxiety whatsoever and you’ve got an EV that does everything we want.”

Before getting to that stage Qualcomm’s idea is to demonstrate inductive charging by getting a fleet of electric taxis that replenish their batteries from charging plates as they move slowly through taxi ranks.

“Then you continue the development of that process and start putting the infrastructure in the roads and junctions and red lights,” explained Davison, “so that as you approach the junction and you slow down, you start charging the vehicle whilst you’re sat at the junction. You also charge the vehicle as you accelerate through the junction and pull away – which is quite often the worst situation for the battery because you have to give more energy per velocity to get the car going.”

Inductive charging technology has already been demonstrated on electric bus routes in America, Germany and Italy, while the city of Gumi is South Korea added inductive charging plates to a 15 mile route for electric buses back in 2013.

“Qualcomm, what they’re doing is really impressive,” said Winkless. “Of course you have to drive along pretty slowly, but a lot of that is to do with the pick-up mechanism of the car. The infrastructure part is much closer to being solved than the car end.”

To get to the ultimate wireless charging for EVs – the inductive charging plates in the road – would require a huge amount of change to existing infrastructure, and with such large-scale investment needed for what would at first be a small, but growing benefit, actually convincing governments to make that investment might be a hard sell in the today’s austerity climate.

“My feeling on that is that it is almost a step too far,” said Steve Hughes, managing director at power equipment manufacturer REO. “Whilst it is interesting, it lends itself more to an integrated system whereby there is electric trains that run on that sort of stuff. But again, you’d have to argue if it is worth it because the existing systems work perfectly well as they are.”

The freedom offered by the automobile has always been one of its most prized assets – the potential to get in and drive to wherever you want. Inductive charging that removes range anxiety for EVs means that they could then be taken all over the world, but this presents another infrastructure hurdle. “It’s going to require cross-border collaborations – and they are not great,” explained Winkless. “Even simple things like electricity – the voltages on train lines are not standard across Europe and not even across some cities in some cases.”

There also safety concerns as well. “You’re basically charging the air with a magnetic field, which is potentially very dangerous,” said Hughes. “It’s conceivable that someone with a pacemaker could get into difficulty if they come into close proximity to that field. It’s the same reason that trains that run on electric [power] have very tight and stringent limits on this field, for exactly that reason; they can’t [be causing] health issues for people that are in the vicinity.”

Qualcomm’s Halo system has built-in safety features that shut off the electromagnetic field if a metallic or living object strays onto the charging pad, and the car and pad must be lined up perfectly for the process to begin. But in order to make its dream of charging lanes on the motorways a reality, Qualcomm will need to seriously address the infrastructure problems.

Inductive charging on the move can take EVs to the next level and range anxiety will be a thing of the past, but in order to get there, massive investment in road infrastructure would be needed in countries across the world.

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