| 摘要 |
PURPOSE:To make a battery case adhere to a sealing plate and improve the properties of sealing by forming a groove in the sealing plate so that it can be returned following the spring back of the battery case. CONSTITUTION:An annular step section 11a is formed by protruding the vicinity of the opening section of a battery case 11 inward. A swirl electrode group 12 wound by inserting a separator between belt-shaped positive and negative electrode plates is inserted in this battery case 11 and a nonaqueous electrolyte is injected. Then an insulating sealing body 14 with a positive electrode terminal 13 is inserted from the opening section of the battery case 11. When the periphery of the sealing body 14 is compressed at sealing, the protrusion sections located at both sides of a groove 14b are spread against the press contact force. Consequently, the sealing body 14 is press-contacted on the opening section of the battery case and the step section 11a and the properties of sealing are improved. In addition, since the protrusion sections of the sealing body 14 are deflected following the spring back of the battery case 11 even if it occurs, the adhesion between the battery case 11 and sealing body 14 can always be maintained. |
