Can I charge batteries w/solar power? XW6648 inverter & Xantrex XW-MPPT60-150 charge controllerll

I'm new here and I know this sounds like a ridiculous question, but I live in an area where there are no solar experts and those that do don't speak English.    At times the grid is down, and the only way I would be able to charge the batteries is from the power generated by the panels.   But the inverter is always on "invert" mode.  Even when all the breakers are off the system still consumes about 30 watts and is still in invert mode.    So on a day when we produce 15 kWh and only use about 5 kWh I would like to be able to send this extra power to charge the batteries.    Is this possible?   What settings do I need to modify?    Charge controller is a Xantrex XW-MPPT60-150.