The ornamental design for a batterycharger, substantially as shown and described.
FIG. 1 is a front perspective view of a battery charger showing our new design;
FIG. 2 is a rear perspective view of the battery charger in FIG. 1;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is a front view thereof;
FIG. 7 is a left side view thereof; and,
FIG. 8 is a right side view thereof.
The design is shown in solid lines in the drawings. Any broken lines in the drawings are directed to environment and are for illustrative purposes only. None of the broken lines form a part of the claimed design.