Abstract: A rechargeable battery, including an electrode assembly performing charging and discharging; a case containing the electrode assembly and an electrolyte solution; cap plate coupled to an opening of the case to seal the opening and containing more electrolyte solution in a receiving groove on an inner surface thereof; and an insulation case coupled to the receiving groove by a protrusion and located between the electrode assembly and the cap plate.

Abstract: A rechargeable battery, including an electrode assembly performing charging and discharging; a case containing the electrode assembly and an electrolyte solution; cap plate coupled to an opening of the case to seal the opening and containing more electrolyte solution in a receiving groove on an inner surface thereof; and an insulation case coupled to the receiving groove by a protrusion and located between the electrode assembly and the cap plate.

Abstract: A secondary battery having a cap assembly, including an electrode assembly; a case in which the electrode assembly is located; a cap assembly having a cap plate coupled to and hermetically sealing the case. A terminal member has a head with a stepped protrusion penetrating the cap plate and insulated from the cap plate by an insulating member. The stepped protrusion presses the insulating member in multiple steps. The terminal member is connected to a positive or negative electrode terminal of the electrode assembly.

Abstract: A battery having a reinforced structure capable of preventing expansion of the bottom of the battery case due to internal pressure generated during charging of a secondary battery is provided. A conventional battery has a problem that in order to achieve higher performance and smaller size, the thickness of the battery case is decreased, and therefore the bottom of the battery case is expanded outward due to increases in the internal pressure caused by gas generated during charging. To solve the above problem, a lower reinforcement plate having a number of protrusions is placed in the battery case and welded to the bottom of the battery case. Accordingly, the lower reinforcement plate prevents expansion of the battery, and performance of the battery can be enhanced.

Abstract: A secondary battery having a cap assembly, including an electrode assembly; a case in which the electrode assembly is located; a cap assembly having a cap plate coupled to and hermetically sealing the case. A terminal member has a head with a stepped protrusion penetrating the cap plate and insulated from the cap plate by an insulating member. The stepped protrusion presses the insulating member in multiple steps. The terminal member is connected to a positive or negative electrode terminal of the electrode assembly.