| 摘要 |
PROBLEM TO BE SOLVED: To improve a sealing property of a sealing structure of an electrolyte injection plug of a conventional lithium secondary battery, and to provide a sealing method of the electrolyte injection plug, which is sufficient to maintain an initial strong sealing property for a long period of time. SOLUTION: A bolt 4 is screwed on a screw part 1c1 on an inner circumferential surface of a lower end threaded cylinder part 1A of the electrolyte injection plug 1 mounted on a battery jar lid 2 of the lithium secondary battery, and the bolt 4 is fastened through an annular packing 3 mounted on an annular step part 1b1 for mounting an annular packing in a space 1b for fitting a bolt head part limitedly formed of an intermediate cylinder part 1B. At that time, a flat upper surface of the bolt head part 4b is positioned lower than the annular step part 1c1 for mounting a flat washer, and a recessed space 7 surrounded by an inner circumferential wall surface of the intermediate cylinder part 1B is positioned above the bolt head part 4b. Then, the recessed space 7 is buried by a flat packing 5 mounted on the upper surface of the bolt head part 4b, and a flat washer 6 is in slide-contact with and fitted to the space 1c for fitting a flat washer surrounded by an upper end cylinder part 1C, the flat washer 6 is mounted over the annular step part 1c1 for mounting a flat washer and an upper surface of the flat packing 5, and an outer circumferential surface of the flat washer 6 and an inner circumferential surface of an upper end cylinder part 1C are laser-welded. COPYRIGHT: (C)2010,JPO&INPIT |
