I am not exactly sure what voltage a typical battery charger charges at, but I would be afraid of damaging some of the appliances at a higher rate than the 13.6 volts the power center produces to charge the batteries. The few times I have used my stand alone battery charger to charge my batteries (quicker than the WFCO), I have taken 1 of the wires off of my battery to play it safe.
Chap , DW Joy, and Fur Baby Sango
2006 Ford F150 Super Cab 4x4
2008 Surveyor 263