Rechargeable battery, rechargeable battery pack and method of manufacturing cap plate of rechargeable battery

A rechargeable battery comprising:

• an electrode assembly comprising an electrode;
• a case configured to accommodate the electrode assembly;
• a cap plate configured to seal an open area of the case;
• and
• one or more terminals electrically connected to the electrode, and coupled to the cap plate,
• wherein the cap plate comprises:
• a vent configured to expel gas generated from inside a cell outward;
• and
• a venting guide wall surrounding the vent, and protruding outward from a surface of the cap plate at a peripheral portion of the vent.

A method of manufacturing a cap plate of a rechargeable battery, comprising:

• molding a cap plate raw material using a first mold having a recess to form a convex portion on an upper surface of the cap plate raw material;
• placing the molded cap plate raw material on one side of a second mold having a through-hole smaller than the convex portion, so that the through-hole of the second mold overlaps with a central portion of the convex portion;
• and
• forming a venting hole and a venting guide wall surrounding the venting hole in the convex portion by applying pressure in a direction from a position of the molded cap plate raw material to the through-hole of the second mold using a punch die smaller than the convex portion.