| 摘要 |
PURPOSE:To improve the leakageproofness of a battery by setting the straightness of a metal sealing cover at the lowermost end of the edge that seals a metal battery case through an insulating gasket with an error of 0.03mm. or less over the whole circumference. CONSTITUTION:A steel battery case 1 is formed by covering the surface with nickel. A sealing cover 3 is made of special steel in a dish form and the edge has a folded riser section 4. A positive electrode agent 2, negative electrode plate 6, and separator 7 are housed in the case 1 and are sealed by the sealing cvoer 3 through an insulating gasket 8. The contact surface 9 between the gasket 8 and the sealing cover 3 and the contact surface 10 between the gasket 8 and the case 1 are coated with a sealing agent. The folded riser section 4 of the sealing cover 3 is formed so that the error in straightness of the lowermost end can be within 0.03mm.. As a result, sealing prressure can be uniformalized and the leakage-proofness of a battery can be improved. |
