| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery cell capable of easily diagnosing life time. SOLUTION: In a lithium ion secondary battery 100, a joining part 126 of a bag-shaped body 120 is joined by first joining force stronger than force generating by an electrode body 110 sealed in the bag-shaped body 120. The inside of a passage 150 installed in the joining part 126 is joined by second joining force weaker than the first joining force, and capable of being peeled off by pressure of gas generated from an electrolyte on the inside of the bag-shaped body 120. Therefore, an end part 152 of the passage 150 communicated with a space on the inside of the bag-shaped body 120 is peeled off by the pressure of gas generated from the electrolyte. Generated gas flows into the passage 150 peeled off, and the passage 150 is swelled to the tip of the peeled off part. COPYRIGHT: (C)2007,JPO&INPIT |
