Metal working – Method of mechanical manufacture – Electrical device making
Reexamination Certificate
2001-11-30
2004-12-21
Ryan, Patrick (Department: 1745)
Metal working
Method of mechanical manufacture
Electrical device making
C429S154000, C429S159000, C429S160000, C429S170000
Reexamination Certificate
active
06833010
ABSTRACT:
The present disclosure relates to subject matter contained in priority Japanese Patent Application Nos. 2000-364826 and 2001-243420, filed on Nov. 30, 2000 and Aug. 10, 2001 respectively, the contents of which is herein expressly incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a prismatic battery module and a method for manufacturing the same. More particularly, the invention relates to a prismatic battery module which is made by connecting a plurality of cells together and designed to reduce an internal resistance, and a method for manufacturing the same.
2. Description of Related Art
A conventional rechargeable battery module made by connecting a plurality of cells together, each having an individual cell case, has a problem that the connection path between the cells is long and the number of connection points is large and each of the connection points has small cross-sectional area, thereby increasing the component resistance leading to the increase of internal resistance thereof.
In consideration of the aforementioned conventional problem, the inventors of this invention have proposed a prismatic battery module
100
including a plurality of cells
2
as shown in
FIGS. 12 and 13
. Reference numeral
3
denotes a prismatic battery case constructed in such a manner that a plurality of prismatic cell cases
4
of cells
2
, each cell case having short lateral walls and long lateral walls, are integrally connected together in series, and each pair of cell cases shares short lateral walls thereof as a separation wall
5
, and further, an upper opening of each of the cell cases is closed by a unitary lid
6
. In the upper portions of outer short lateral walls of the outermost cell cases and the separation wall
5
between the adjacent cell cases
4
are formed connection holes
7
. Within each of the cell cases
4
, an electrode plate group
8
constructed by alternately stacking rectangular positive and negative electrode plates interposing a separator therebetween is accommodated together with an electrolyte. The positive and the negative electrode plates constituting the electrode plate group
8
project from the electrode plate group in opposite directions to form a lead portion
9
a
of the positive electrode plate and a lead portion
9
b
of the negative electrode plate, respectively. To the side ends of the lead portions
9
a
,
9
b
are connected collector plates
10
a
,
10
b
, respectively, by welding or the like.
In the upper portions of the collector plates
10
a
,
10
b
are formed connection projections
11
to be fitted into the connection holes
7
, and the connection projections
11
of the collector plates
10
a
,
10
b
as positive and negative poles respectively are connected to each other between the adjacent cell cases
4
by welding. Furthermore, in the connection holes
7
of the outer short lateral walls of the outermost cell cases
4
are mounted connection terminals
12
as either a positive or negative pole, and a connection projection
13
of the connection terminal
12
and the connection projection
11
of either the collector plate
10
a
or
10
b
are connected to each other by welding. Thus, a plurality of cells
2
accommodated in the prismatic battery case
3
are connected together in series.
Additionally, in the lid
6
are provided a communication path
14
for balancing the internal pressure between the cell cases
4
, a safety vent (not shown) for discharging the pressure when the internal pressure of the cell case
4
exceeds a predetermined value and a sensor fixing hole
15
for fixing a temperature sensor thereto to detect the temperature of the cell
2
.
According to the above-described construction of battery, since the electrical communication path from the positive and negative electrode plates of the electrode plate group
8
to the respective lead portions
9
a
,
9
b
is short and further the adjacent lead portions
9
a
,
9
b
of the associated electrode plate groups are connected to each other via the associated collector plate
10
a
,
10
b
within the prismatic battery case
3
, the connection path between the electrode plate groups is short and the number of connection points is small, thereby allowing the prismatic battery module to reduce the component resistance included therein and in proportion thereto, reduce the internal resistance.
However, although the prismatic battery module
100
shown in
FIGS. 12 and 13
is constructed so that the connection path from the positive and negative electrode plates to the respective collector plates
10
a
,
10
b
via the respective lead portions
9
a
,
9
b
is short, as is denoted by arrows in
FIG. 14
, the adjacent collector plates
10
a
,
10
b
of the associated electrode plate groups are connected at one point of both ends of the connection projections
11
located at the upper portions of the adjacent collector plates by welding and therefore, there have been seen problems that the entire connection path between the adjacent electrode plate groups becomes longer and in addition, the internal resistance between the cells becomes higher since the electrical communication between the adjacent collector plates is performed at only one point. Furthermore, there have also been seen problems that the collector plates
10
a
,
10
b
employed in the battery
100
increases the manufacturing cost of battery correspondingly, and further, it is necessary to arrange the collector plates
10
a
,
10
b
on both sides of the electrode plate group
8
and to form the upper portion of the collector plates
10
a
,
10
b
so as to project beyond the upper end of the electrode plate group
8
, thereby forcing enlargement of the volume of the cell case
4
.
SUMMARY OF THE INVENTION
In consideration of the above problems seen in the conventional technique, an object of the present invention is to provide a prismatic battery module in which the internal resistance per cell is reduced, and a method for manufacturing the same.
A prismatic battery module according to a first aspect of the invention includes a prismatic battery case constructed by connecting a plurality of prismatic cell cases together in series, each pair of cell cases sharing a separation wall; an electrode plate group formed by alternately stacking positive and negative electrode plates interposing a separator therebetween and further forming lead portions by projecting one side portion of the positive electrode plates and one side portion of the negative electrode plates in opposite directions, respectively; and collectors connected to the lead portions on both sides of the electrode plate group, in which the prismatic battery module is further constructed such that adjacent electrode plate groups are connected to each other by connecting adjacent collectors to each other through a connection aperture formed in a central portion of the separation wall and a sealing material is applied to each space between each of the separation walls around the connection aperture and each of the collectors. As the adjacent collectors are connected through the connection aperture formed in the central portion of the separation wall, the electrical communication path between the electrode plate groups becomes shorter allowing the reduction of the internal resistance and the upper portion of the collector is not required to project from the electrode plate group, resulting in the volume reduction of prismatic battery case.
A prismatic battery module according to a second aspect of the invention includes a prismatic battery case having a single internal space therein; an electrode plate group formed by alternately stacking positive and negative electrode plates interposing a separator therebetween and further forming lead portions by projecting one side portion of the positive electrode plates and one side portion of the negative electrode plates in opposite directions, respectively; and collectors connected to the lead portions on both sides of the electrode plate
Asahina Takashi
Eto Toyohiko
Hamada Shinji
Sekimori Toshiyuki
Parsons Thomas H.
Ryan Patrick
LandOfFree
Prismatic battery module and method for manufacturing the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Prismatic battery module and method for manufacturing the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Prismatic battery module and method for manufacturing the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3294454