Film packaged battery having a cupped portion
A battery is fabricated on the basis of at least one of the following four concepts, i.e., lead terminals passing through a package not lower than the uppermost surface of an electrolyte cell, lead terminals projecting from a package in directions opposite to each other, a film package with a crushed portion expandable for accumulating gas and sheets of gas barrier sealant for keeping the boundaries between component parts of a package sealed; the seal is hardly broken so that the battery is durable and highly reliable.
1. A film packaged battery comprising:
a film package made of an expandable material and having a cup portion defining a space and a deformable portion expandable in a first direction, said deformable portion extending into said space when said space is lower in pressure than an ambience around said battery, and said deformable portion recovering to an initial shape when gas is generated in said package;
an electrolyte cell having electrodes laminated in a second direction different from said first direction, received in said space and sealed in said film package, and
terminals having respective inner portions electrically connected to said electrolyte cell and respective outer portions projecting to the outside of said film package.
2. The film packaged battery as set forth in claim 1 , wherein said deformable portion outwardly projects from an outer surface of said film package therearound when the pressure in said space is higher than the pressure of said ambience.
3. The film package battery as set forth in claim 2 , in which said deformable portion was formed after said cup portion wider in bottom area than said electrolyte cell had been formed in said film package, said formed cup portion having said initial shape.
4. The film packaged battery as set forth in claim 2 , in which said deformable portion was retracted when vacuum was developed in said space, and the development of said vacuum was carried out after said cup portion was formed in said film package.
5. The film packaged battery as set forth in claim 2 , in which said film package is separable into two sheets of film or a sheet of foldable film, and said deformable portion is formed in one of said two sheets or a part of said foldable film.
6. The film packaged battery as set forth in claim 4 , in which said film package is separable into two sheets of film or a sheet of foldable film, and said deformable portion is formed in one of said two sheets or a part of said foldable film.
7. The film packaged battery as set forth in claim 5 , in which said deformable portion was formed by using a deep drawing.
8. The film packaged battery as set forth in claim 6 , in which said cup portion was formed by using a deep drawing.
9. The film packaged battery as set forth in claim 5 , in which said two sheets or two parts of said foldable sheet are bonded to each other in said space in such a manner as to be resistive against an expansion of said space in said another direction.
10. The film packaged battery as set forth in claim 1 , in which said electrolyte cell has a coil-like shape.
11. The film packaged battery as set forth in claim 1 , in which said electrolyte cell includes plural plates adhered to one another.
12. The film packaged battery as set forth in claim 1 , in which said electrolyte cell includes plural plates, and a retainer keeps said plural plates held in tight contact with one another.
13. The film packaged battery as set forth in claim 12 , in which said retainer is a piece of adhesive tape adhered to said plural plates.
14. The film packaged battery as set forth in claim 1 , in which said electrolyte cell includes non-aqueous electrolyte.
15. The film packaged battery as set forth in claim 12 , wherein said retainer presses said plural plates to one another.
16. A film packaged battery comprising:
a film package made of an expandable material and having a cup portion defining a space, said cup having walls expandable in a first direction, said walls having an inwardly extending dent or bulge that extends into said space when said space is lower in pressure than an ambience around said battery and outwardly expands when the pressure in said space is higher than the pressure of said ambience;
an electrolyte cell having laminated electrodes received in said space and sealed in said film package; and
terminals having respective inner portions electrically connected to said electrolyte cell and respective outer portions projecting outside of said film package.