How to charge my batteries
 

I'm not sure where to put this.

I bought two 6 volt costco golf cart batteries for my camper to power my led lights and such when I'm camping. I'm trying to use those same batteries to power some lights, microwave, and a tv at my deer cabin. Mainly just the lights. I currently use a 7500watt generator running the whole time were at camp to power everything. It gets expensive. I was hoping to use the batteries to power the lights. And use the generator for the microwave and tv.

My question is what is the best way to charge the batteries and power my lights (inverter)? I've seen people take a 5 hp motor and a GM one wire alternator to charge batteries. Could I build one of those and use a big inverter to power everything. When I want to use the microwave I start the 5 hp motor so it will change my batteries and keep up with the power draw? Or do I buy a good inverter like my camper has and plug it into the generator? I'm looking for something that can run pretty seamless. I don't really want to have to unplug the cord from the inverter and in to the generator when I want to run the microwave. Well I don't mind but I know my dad isn't going to do that. He would rather spend the money on fuel to run the generator the whole time. Or is there something else I haven't mentioned?

Does your generator have electric start?

Yes it does. I have a 5500 watt one that doesn't which might be better on gas though.

Light, microwave, and a TV? I'd suggest a Honda inverter generator. They are very quiet. I was 15 feet away from one talking to some people and they had a fan running in their camp and they asked how it was running when the generator was off. I had to tell them to walk a little closer and listen, they didn't know the generator was running.

I figure 2000 watts should run a microwave without turning off the lights or the TV if the lights and TV aren't huge energy hogs. The Honda EU2000i costs about a grand but if you are camping, I'd say it's worth it.

These generators throttle down to a lower speed when their load is low and they run for a long time off of a gallon of gas. Longer than a 5HP motor connected to an alternator would.

Use a universal input (100-240V) 12V PSU tweaked to output about 14.4V (a few hacked PC PSUs would work nicely), then modify the generator to slow it down to about 1/2 speed when full output is not needed. Then run the PSU from the 240V output.

Using what you have to do what you want to do will not be highly efficient.

Using a 5000-7500 watt motor-generator rig to charge 2 batteries and run a microwave is serious overkill. Unless you add way more batteries, they will never charge fast enough (nor hold enough energy) to keep the generator from running much less when your demand is high.

When your demand is low, the two battery bank will only hold about one battery rating of mah before you would need to recharge them.

I run a 2800 watt generator for everything. I have a large garage style battery charger that I use for a back-up. It runs my small microwave just fine..

I own a 2000 watt inverter but only used it one time. I connected it to my battery and test drove the microwave. That thing draws ~60 amps with the microwave on! I put the inverter back in the box and run the microwave with the generator.. LOL..

I don't believe that 6 golf cart batteries will provide that much current to operate a microwave for very long. It takes a big battery to provide large current for a length of time. It may work for a minute or two but I bet the voltage will drop very fast under those conditions..

I run 8 of these connected in series-parallel and it made them grunt.. ;)

http://www.dcbattery.com/rollssurrette_s600.pdf