You have 2 types of batteries: engine battery and house battery(s)
Engine battery helps the engine start - just like a normal car battery
House battery(s) - is used by the house section of the RV for lights and stuff
Your house batteries won't be powerful enough to run the rear air conditioner or microwave. You will need to run the generator or connect up to external power for them.
The batteries can be charged by engine, generator, solar panel or external power (i.e. from a wall outlet or similar)
This video will help explain some of the technical stuff. I know it's not for your RV, but it shares the common systems with all/most RVs.
http://www.youtube.com/watch?v=GKdr4Z1LBKY#t=269Make sure you have some reserve money. Things break.
