The ornamental design for a batterypack for a vacuum cleaner; as shown and described.
FIG. 1 is an exploded perspective view of a battery pack for a vacuum cleaner of the present invention, with an environmental showing of a bracket for receiving the battery pack and an upright handle of a vacuum cleaner;
FIG. 2 is a left side elevational view showing the front side of the battery pack of the present invention as shown in FIG. 1;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a top elevational view thereof;
FIG. 5 is a bottom elevational view thereof;
FIG. 6 is a side elevational view thereof; and,
FIG. 7 is the elevational view of the side opposite that shown in FIG. 6.
In the drawings, the broken lines environmental subject matter that forms no part of the claimed design.