If you are going to go with the battery/inverter combo, and given the input from curtludwig it should work just fine. You should however consider this: No deep cycle battery should be discharged below the 50% capacity mark. A deep cycle battery will require more than a car alternator to recharge it when used like this. If you do not adhere to proper discharge and charging regimens the battery will not last. For charging you will need a 3 stage battery charger, like a good marine charger, to put the juice back in as fast as possible and not damage the battery. As far as battery size take a look at group 31 sized batteries. A decent charger should not be ignored. The system will simply not perform to your expectations if the battery isn't up to it. If you want to know how to care for batteries in deep cycle conditions the marine applications are probably the most applicable. RT

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