It has gotten to the point where I do not even bother with wireless chargers in vehicles for this exact reason. The only manufacturer I have found that does not microwave your phone while charging in the car is Tesla (I am sure there are others, just have not heard of or experienced any). But my BMW just cooks my phone for 20 minutes for a mediocre 3% charge. Not worth it.
I would avoid wireless chargers in cars at all costs as excessive heat can damage your phone.
If you are adamant about a wireless charger in your car, look into something that plugs into the cars USB ports and secures your phone while charging. This will prevent long term damage to your phone by mitigating heat.
With that said, avoid those vent mounted holders for your phone as well. If you ever have your phone in front of it while blasting hot air, you'll also have negative side effects.