Secondary Battery and Method for Manufacturing Secondary Battery

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

• sealing an edge of an outer packaging by forming an edge sealing portion at the edge of the type-outer packaging having an accommodation portion for accommodating an electrode assembly and a collection portion for collecting gases produced during charging and discharging of the electrode assembly;
• venting the gases collected in the collection portion during the charging and discharging of the electrode assembly to outside of the outer packaging;
• and
• forming a division sealing portion between the accommodation portion and the collection portion in the outer packaging to divide the accommodation portion from the collection portion after the degassing step,
• wherein sealing the edge of the packaging further includes:
• forming an additional sealing portion extended from the edge sealing portion formed between the accommodation portion and the collection portion, wherein the additional sealing portion is disposed in the collection portion and is spaced apart from the division sealing portion.