2003 Nissan Altima CHARGING A 200 AMP BATTERY

I would never use your car as a battery charger like that. Go buy a battery charger harbor freight has some cheap ones. They also have cuppons for 20 percent off sometimes. You can damage your car trying to charge batteries with your car.

The reason I say it should not be done is because your alternator in your car is designed to keep your battery in your car charged while the engine is running an help maintain the batteries charge while using the ac lights etc on the car. Its not made to charge a aux battery in addition to the one in your car or charge that battery. You could damage your alternator or even the computer in your spiking the computer with unstable voltages. The car is not designed to run dual batteries or act as a temporary battery charger to help maintain a emergency battery to run your refrigerator. So I am not going to tell you to doing something that you could damage your car. Get a generator that runs on gasoline or propane or even natural gas they have them. As long as you have a place to run it outdoors. Your best would be to talk to place that specialized in that kind of things.I am sure you them by you if you loose power for three days.I don't know of any battery that can run a refrigerator for three days without charge. That's why I say talk to them.

The reason I suggested the battery charger I thought you were suggesting the car to charge the aux battery after a storm or to maintain it. Not run the power invertor off of it.