Venting apparatus, secondary battery, and method of manufacturing secondary battery

A secondary battery, comprising:

• an electrode assembly;
• a case accommodating the electrode assembly;
• a terminal plate combined with the case, the terminal plate having a vent;
• a sub-terminal plate under the terminal plate;
• a spring having a top connected to the sub-terminal plate;
• a vent plate connected to a bottom of the spring, the vent plate having high and low positions that are changeable in response to a pressure within the secondary battery;
• and
• a discharge preventer on an opening of the case, the discharge preventer being under the vent plate and being configured to prevent a discharge of a material other than a gas within the secondary battery.

A method of manufacturing a secondary battery, the method comprising:

• providing an electrode assembly;
• accommodating the electrode assembly in a case;
• providing, on an opening of the case, a discharge preventer that prevents a discharge of a material other than a gas within the secondary battery;
• providing, on the discharge preventer, a vent plate having high and low positions changed in response to pressure within the secondary battery;
• providing a spring;
• connecting the vent plate to a bottom of the spring;
• connecting a sub-terminal plate to a top of the spring;
• providing, at a top of the sub-terminal plate, a terminal plate including a vent that enables the gas within the secondary battery to be discharged;
• and
• combining the terminal plate and the case.