| 摘要 |
Disclosed herein is a plate-shaped secondary battery constructed in a structure in which an electrode assembly of a cathode/separator/anode structure is mounted in a battery case, and the battery case is sealed by thermal welding, wherein the secondary battery has at least one valve (one-way exhaust valve), having a small thickness, mounted at a sealed portion, formed at the outer circumference of an electrode assembly receiving part of the battery case, for allowing internal high-pressure gas to be exhausted out of a battery cell and preventing external gas from being introduced into the battery cell. The secondary battery according to the present invention has the effect of effectively exhausting internal high-pressure gas generated during the abnormal operation of the battery, such as overcharge, out of the battery case, while maintaining the sealability of the battery case, thereby simultaneously improving the efficiency and safety of the battery. |
