I used a different laptop. I was originally going to use a Dell but chose a Gateway instead. I'm not a fan of Gateway but they haven't gone to this on any of theirs that I've seen (yet). It works well in my wife's van.
The other option would be to power the laptop from an inverter so you're using the brick...not the cleanest solution but it works (I have to run the one in my car that way in order to use the docking station since it pulls 160W).