The fact that McLaren is testing an all-electric supercar is no longer secret. With the P1 bringing the first hybrid McLaren on public roads and gasoline-electric drivetrain set to power half of all McLarens sold by 2022, a full EV is the next logical step for the British firm. According to its engineers, testing is now well underway, but McLaren is struggling to create a drivetrain that delivers track-capable performance. Specifically, the biggest issue is battery technology, which can't yet provide the energy needed for fast laps at the race track.

EV range, and it would be flat as a pancake at the end|align=center>

“Let’s say you want to drive on track for half an hour,” said Dan Parry-Williams, McLaren's engineering design director. “If that was an EV, that car would have over 500 miles of EV range, and it would be flat as a pancake at the end. The energy required to do really high performance on track is staggering. And then you have to recharge it.”

This isn't surprising, to be honest. There are carmakers that have designed full-fledged race cars in the past, but only as one-lap showcase vehicles at major events. Some have managed more than just one lap but not at a pace that would give the gasoline or hybrid vehicles a run for their money. Formula E is a good example of EVs that can cover several laps per charge but again, the pace is far inferior to that of conventional racers. But McLaren isn't giving up. And while progress is slow, technology is evolving at a promising pace.

A production model, however, is still a few years away. “We’ve got a pure EV mule, and part of the reason for that is to ask how we can deliver driver engagement in a fully electric world,” added Parry-Williams. “But there’s still quite a journey from here to there in terms of our products.”

"You can potentially manage with a niche car,” Parry- Williams told Autocar. “If you exhaust the battery but then have to do one recharging lap, that strikes me as being okay. But if you haven’t got an on-board generator you’ve got a full EV, you haven’t got the luxury of doing that.”

All told, McLaren is more than capable of building an all-electric vehicle right now, but it would not be a supercar. In order to reach performance similar to the P1, battery technology, especially in the power density field, needs to evolve farther. For the time being, producers seem to focus on energy-dense batteries, which are good providing long range. This is obviously good for passenger cars like the Nissan Leaf and Tesla Model 3 but leaves supercars on the drawing table for a few more years.

References

McLaren P1

Read our full review on the 2014 McLaren P1.

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