yes there is a way, not sure if there are laptop chargers for cars yet, but there are small amps/power inverter that plugs into your car and have normal 2 and possibly 3 prong plugins on them. Sorry i havent had one for awhile but im not sure if all come with 3 prong plugins. i gave some examples down below of what they are.
Whistler - 200-Watt Power Inverter
CyberPower - 100W DC to AC Power Inverter with USB Connection