| 摘要 |
PURPOSE:To provide a sealed lead acid battery which enhances its sealing property for high reliability. CONSTITUTION:A sealed lead acid battery has a positive electrode and a negative electrode in a pole plate group stored in a battery jar with the respective pole columns 1 penetrating a hole 3 in an inside cap 2 enclosing the battery jar so that its head is protruded above the inside cap 2 and the gap to the hole 3 in the inside cap 2 is covered with an O-ring 4 and resin filler 5. The 0-ring 4 made of rubber has a volume expansion coefficient of 0.3% or larger when it is submerged in 40wt.%-concentration dilute sulfuric acid at 70 deg.C for twenty-four hours. When dilute sulfuric acid electrolyte creeps up to the O-ring, the O-ring absorbs the dilute sulfuric acid electrolyte and expands its volume to ensure blockage of the gap of the O-ring to the pole column and the inside cap and to prevent the further creep of the dilute sulfuric acid electrolyte. |
