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EVs immobilised by flat batteries or breakdowns

A few weeks ago while driving back from a weekend away we came across several long queues on the Autobahn apparently due to stuck vehicles. One, on our carriageway, was caused by a car half on the hard shoulder and half in the slow lane. The police were there and I couldn’t see why two police officers and the driver couldn’t move the car a few meters on the level. A little further on there was a car stopped in the middle lane of the other carriageway. Again the police were in attendance but seemed unable to move the vehicle to the hard shoulder. As there was a good 5km of queue behind this one there should have been enough people to pick it up and carry it off the road.

After some internet searching I came across this article:

https://www.motoringresearch.com/car-news/transport-minister-astonished-hazard-electric-car-motorway-breakdowns/

“When an electric vehicle ceases to function, it stops; it does not coast in the way that other vehicles do,” said Barnoness Randerson, Lib Dem transport spokesman, during the debate.

“Smart motorways are supposed to be the future, but the future is electric. Those vehicles stop very suddenly. They also cannot be towed; they have to be put on a low-loader, which is a much more complex and longer process that will put rescue teams in greater danger.

Indeed, during a test of real-world electric car range, Carwow found that some EVs were “difficult to move” when the batteries were run truly flat. Most cars in the test ‘locked up’ once they were out of juice. The tested included everything from the Tesla Model 3 and Audi E-tron, to the Kia e-Niro and Nissan Leaf.

 

Is this true/realistic or has the problem been somewhat exaggerated? I am used to manual cars with conventional handbrake that can easily be pushed. Are EVs such a problem to move when something goes wrong? What about conventional cars with electric handbrakes, can they get stuck as well?

Parents
  • Not that I'm an expert by any stretch of the imagination (I'll leave that to  and the volunteers in the Automotive and road transport systems Network) but it seems that you can push an EV to the side of the road if needs be, they just can't be towed. Blue car

    My 2001 Audi can't be towed more than 30 miles at 30mph either, which made breaking down on a busy dual carriageway in Stevenage and wanting to be towed up the motorway to my trusted mechanic some 15 miles away quite fun Joy

  • Lisa, it's off topic but I presume your Audi is an automatic? If so, it will probably have a wet multiplate clutch in the gearbox. Wet being wet with oil which is used to cool the clutch plates and lubricate the gears. The clutches aren't designed to have a high speed difference between the plates for long times, just pull away from standstill and shifting gears. When the vehicle is being towed the one side of the clutch is stationary (engine not running) and the other side is spinning due to being towed down the road. This causes friction and the oil to heat up and can damage the oil or clutch plates if it gets too hot for too long. Hence the manufacturer limiting the speed and duration of the tow.

    Regards
    Pete

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  • Lisa, it's off topic but I presume your Audi is an automatic? If so, it will probably have a wet multiplate clutch in the gearbox. Wet being wet with oil which is used to cool the clutch plates and lubricate the gears. The clutches aren't designed to have a high speed difference between the plates for long times, just pull away from standstill and shifting gears. When the vehicle is being towed the one side of the clutch is stationary (engine not running) and the other side is spinning due to being towed down the road. This causes friction and the oil to heat up and can damage the oil or clutch plates if it gets too hot for too long. Hence the manufacturer limiting the speed and duration of the tow.

    Regards
    Pete

Children
  • It’s not an auto Pete,️ it’s manual and a quattro. It’s something to do with it being a 4wd and not damaging the haldex controller or so I believeRelaxed️ ️

  • Ah OK, I think it is the same reason the oil heating up, but rather than clutches in the transmission the haldex uses a differential pump, which I would have thought would have been OK to tow if all four wheels are on the ground and therefore going at the same speed. It would be a problem if two wheels were lifted.