The ornamental design for a rechargeablebattery, as shown and described.
FIG. 1 is a first perspective view of a rechargeable battery showing our new design;
FIG. 2 is a front view thereof, the rear side being a mirror image;
FIG. 3 is a left side view thereof, the right side being a mirror image;
FIG. 4 is a top plan view thereof, wherein the broken lines in the drawings are for the purpose of illustrating unclaimed portions of the charging case and form no part of the claimed design;