| 摘要 |
PURPOSE: To prevent nonaqueous electrolyte secondary batteries from having an adverse effect on each other, when the batteries are stacked for use as a combined battery, by forming a groove extended in a plurality of directions on the side of a battery vessel not in parallel to positive and negative electrode plates. CONSTITUTION: A flat battery vessel 10 is provided with a safety device, and a linear groove 21a is formed on the side 10b of the vessel 10 not a parallel plane 10a to a positive electrode plate 2 and a negative electrode plate 3, extending approximately over an entire lengthwise direction. Also, a groove 21b is formed in such a state as extending orthogonally from the groove 21a. Thus, this relatively small safety device can well cope with the gradual rise of internal pressure. In the case of a sudden rise in internal pressure such as in the case of abnormal charging and discharging processes, the side 10b is deformed and, then, broken to discharge gases or the like outside therefrom. As a result, safety can be maintained and other nonaqueous electrolyte secondary batteries are not adversely influenced. |
