Highly reliable and durable battery and process for fabrication thereof
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 power supply unit, comprising:
plural batteries each having a same structure, each of said plural batteries including:
a package including a first cup-shaped component part and a second component part directly on and bonded to said first component part for closing said first component part, said first component part having a base and angled sides, said base of said first component part having a first length, said second component part having a base and angled sides, said base of said second component part having a second length greater than said first length;
an electrolyte cell received in said cupshaped component part, and hermetically sealed in said package; and
lead terminals having respective inner portions electrically connected to said electrolyte cell, respective outer portions projecting from said package and respective intermediate portions passing through the boundary between said first component part and said second component part and on a level with or higher than the upper surface of said electrolyte cell,
wherein said plural batteries are stacked one on top of another and are electrically connected together to form a power supply unit, and
wherein said second component part of one of said plural batteries is made from a flexible film.
2. A power supply unit, comprising:
plural batteries each having a same structure, each of said plural batteries including:
a package having a first component part formed with a downwardly directed cup and a second component part placed on and bonded to said first component part for closing said cup;
an electrolyte cell received in said cup, and hermetically sealed in said package; and
lead terminals having respective inner portions electrically connected to said electrolyte cell, respective outer portions projecting from said package and respective intermediate portions passing through the boundary between said first component part and said second component part and on a level with or higher than the upper surface of said electrolyte cell,
wherein said plural batteries are stacked one on top of another with a positive lead of a first one of said plural batteries overlying a negative lead of a second one of said plural batteries, and are electrically connected together to form a power supply unit,
wherein a second component part of said first one of said plural batteries is made from an expandable film, and
wherein an upper surface of said second component part of said first one of said plural batteries has a first length with respect to a longitudinal direction of said lead terminals and a bottom surface of a first component part of said second one of said plural batteries has a second length with respect to said longitudinal direction of said lead terminals, said first length is greater than said second length,
wherein said cup has a first base and first sides extending at a first angle from said first base and wherein said second component has a second base and second sides extending at a second angle from said second base, said second angle being greater than said first angle.
3. The power supply unit as set forth in claim 2 , further comprising a spacer between said first one of said plural batteries and said second one of said plural batteries.
4. The power supply unit as claimed in claim 2 , wherein said upper surface of said first battery and said lower surface of said second battery are substantially parallel to each other.
5. The power supply unit as claimed in claim 2 , wherein said expandable film is a synthetic resin.