FIG. 1 is a front perspective view of an inverter charger system showing our new design; FIG. 2 is a back perspective view thereof; FIG. 3 is a front view thereof; FIG. 4 is a left side view thereof; FIG. 5 is a right side view thereof; FIG. 6 is a back view thereof; FIG. 7 is a top plan view thereof; and, FIG. 8 is a bottom plan view thereof.