Panasonic Corporation

Yoshio Goda

Norio Suzuki

Seiichi Kato

Tadahiro Tokumoto

Yoshinori Koyanagi

Masaji Moriwaki

Toshiki Ishikawa

Kiy Shi Yamashita

A battery case is made by cutting from a blank case of a bottomed cylindrical battery case having an unwanted portion at an opening portion the unwanted portion from the case wall in the circumferential direction by a blade. The cutting of the case wall is performed so as to render a cutting-end portion higher than a cutting-start portion. Thus, re-cutting of the cutting-start portion by the blade after it has already completed one rotation can be avoided. As a result, the generation of thread-like chips from re-cutting of the cut surface can be avoided.

Battery can with cutting-edge portion higher than cutting start portion, manufacturing method and manufacturing device therefore, and battery using the same

A tensile stress is applied to solidified resin. The tensile stress is so small that the solidified resin formed in the sprue by solidification of molding material does not break and is so large that the solidified resin formed in the sprue is separated from the inner surface of the sprue due to a reduction in the diameter of the cross sectional area thereof. For the application of such a tensile stress, the runner stripper plate holding the solidified resin is moved away from the nozzle and sprue bushing. This state is maintained for a predetermined time to separate the solidified resin from the inner surface of the sprue.

Method and apparatus for producing battery pack

A top sealing plate used for a battery includes a filter, a cap, and a valve body. The filter has a valve hole and upper opening; the cap has a convex portion and a flange portion disposed around the convex portion; the opening end of the upper opening of the filter has a bend portion; and the outer periphery end of the flange portion of the cap and the bend portion are caulked and joined to each other. The caulked portion includes both states of contact, that is, a strong contact portion and a weak contact portion, between the surface of the outer periphery end of the flange portion and the bend portion. By this configuration, the electric contact resistance between the cap and the filter will be greatly reduced. In addition, the contact resistance is stabilized at a low level. Further, the internal resistance of the battery is lowered, thereby improving the battery performance.

Top sealing plate, battery using the top sealing plate, and method of manufacturing the battery

Growing community of inventors

Osaka, Japan

Yoshio Goda