Hi All, I am trying to figure out how power charging my MaBook will be on my battery. It is a Marine 24 battery. The MacBook is a MacBook Pro 2015 model. My best info is it has uses the 85 watt charger. If I am calculating correctly: 85 watts/12 volts = 7 amps. Is this per hour? I have a dc connector for the MacBook. It looks like this. It currently works great in the car but I would like to use it in the popup. Thanks for any help!