PURPOSE: To keep off a positional slip of rubber for a safety valve during assembling, by applying a bonding agent to an inner bottom surface of a straight pole terminal.

CONSTITUTION: A straight pole terminal 2 is turned upside down, then first placed on a welding block 1, and rubber 3 having such a character as being deformed when reaching the fixed pressure is placed on this straight pole terminal 2. At this time, an instant bonding agent 6 is applied to a backside bottom surface of the straight pole terminal 2 in advance, whereby a positional slip after the rubber 3 is placed on the straight pole terminal 2 is kept back. With this constitution, the straight pole terminal 2 comes possible to be welded to a cover, leading to improvements in productivity, while drawbacks in a storage battery such as damage to the battery due to an abnormal internal pressure rise and so on are solvable.