computer car charger

Welcome to Apple Support Communities.

MacBooks use a 60-watt charger, and some MacBook Pros use an 85-watt charger.

So, buy a 100-watt (or larger capacity) inverter that plugs into your car's '12-volt power port' (used to be called the cigarette lighter outlet), and plug your Mac charger in to the inverter. Problem solved.

Some inverters are now designed in the form of beverage cups to easily fit in a cupholder.

Here are some on Amazon http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=car +chargers+for+macbooks

Your MacBook uses a 60 watt charger but can use an 85 watt charger without any problems. It cannot use a 45 watt MacBook Air charger.