摘要 |
A cap assembly comprises a cap formed of a metal having electric conductivity, a safety vent formed of a metal having electric conductivity and disposed below the cap, and a positive temperature coefficient (PTC) resistance layer which includes a conductive polymer composition having PTC characteristics and which is disposed between the cap and the safety vent. A secondary battery comprises a can including an open portion at one side, an electrode assembly accommodated in the can, and a cap assembly as described above. |