Honestly, uncontrollably fast is probably the way to go. If he had any ability to steer, he should have kept it on the motorway and let the batteries die. At top speed, the car won't drive for more than 10-20 minutes tops.
Even if you can't steer and can't drive, it doesn't mean you can't try to keep fighting for control over the car. Pilots have been dying this way for decades.
Honestly, uncontrollably fast is probably the way to go. If he had any ability to steer, he should have kept it on the motorway and let the batteries die. At top speed, the car won't drive for more than 10-20 minutes tops.
Even if you can't steer and can't drive, it doesn't mean you can't try to keep fighting for control over the car. Pilots have been dying this way for decades.