U.S. patent application number 09/928189 was filed with the patent office on 2002-03-07 for battery cell having notched layers.
Invention is credited to Gross, Oliver J..
Application Number | 20020028377 09/928189 |
Document ID | / |
Family ID | 23794166 |
Filed Date | 2002-03-07 |
United States Patent
Application |
20020028377 |
Kind Code |
A1 |
Gross, Oliver J. |
March 7, 2002 |
Battery cell having notched layers
Abstract
The invention provides a battery cell including an electrode
having an area defined by a perimeter including an edge, a counter
electrode having an area defined by a perimeter including an edge,
and a separator having an area defined by a perimeter including an
edge. The separator is sandwiched between the electrode and the
counter electrode in a layered relationship with at least portions
of the edges being contiguous. The separator and one of the
electrode and the counter electrode each include a first notch in
the edge exposing a portion of the other of the electrode and
counter electrode. The separator and the other of the electrode and
the counter electrode each include a second notch in the edge
exposing a portion of the one of the electrode and the counter
electrode. A method of producing a battery cell having a plurality
of film layers, a plurality of current collector layers, and at
least one separator layer, with each current collector layer
including a predetermined lead portion, is also provided. The
method includes the steps of: providing at least one notch in each
layer, and stacking the layers with the notches arranged with one
another to expose the predetermined lead portion of each current
collector layer.
Inventors: |
Gross, Oliver J.;
(Henderson, NV) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, PLC
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
23794166 |
Appl. No.: |
09/928189 |
Filed: |
August 9, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09928189 |
Aug 9, 2001 |
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09451901 |
Dec 1, 1999 |
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6294288 |
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Current U.S.
Class: |
429/129 ;
29/623.1; 429/152; 429/161; 429/233 |
Current CPC
Class: |
H01M 50/463 20210101;
H01M 50/531 20210101; H01M 6/40 20130101; Y02P 70/50 20151101; H01M
50/46 20210101; H01M 4/0402 20130101; Y02E 60/10 20130101; H01M
50/54 20210101; H01M 10/0436 20130101; Y10T 29/49108 20150115; H01M
50/50 20210101; H01M 6/46 20130101; H01M 4/70 20130101 |
Class at
Publication: |
429/129 ;
429/233; 429/152; 429/161; 29/623.1 |
International
Class: |
H01M 002/18; H01M
004/70; H01M 002/26 |
Claims
What is claimed is:
1. A battery cell, comprising: an electrode having an area defined
by a perimeter including an edge; a counter electrode having an
area defined by a perimeter including an edge; and a separator
having an area defined by a perimeter including an edge; said
separator sandwiched between said electrode and said counter
electrode in a layered relationship with at least portions of said
edges being contiguous; said separator and one of said electrode
and said counter electrode each including a first notch in said
edge exposing a portion of the other of said electrode and said
counter electrode.
2. The battery cell of claim 1, wherein said separator and the
other of said electrode and said counter electrode each include a
second notch in said edge exposing a portion of said one of said
electrode and said counter electrode.
3. The battery cell of claim 2, wherein said one of said electrode
and said counter electrode is said electrode, and the other of said
electrode and said counter electrode is said counter electrode.
4. The battery cell of claim 3, wherein said perimeter of said
electrode includes a corner portion defined by said edge and said
second notches.
5. The battery cell of claim 4, wherein said electrode includes a
film layer and a current collector layer with said current
collector layer including said electrode corner portion and said
film layer including a third notch exposing said electrode corner
portion.
6. The battery cell of claim 5, wherein said perimeter of said
counter electrode includes a corner portion defined by said edge
and said first notches.
7. The battery cell of claim 6, wherein said counter electrode
includes a film layer and a current collector layer with said
current collector layer including said counter electrode corner
portion and said film layer including a fourth notch exposing said
counter electrode corner portion.
8. The battery cell of claim 7, wherein said counter electrode
includes said separator with said counter electrode film layer
sandwiched between said counter electrode current collector layer
and said separator in a layered relationship.
9. The battery cell of claim 8, including an another counter
electrode similar to said counter electrode, with said another
counter electrode stacked in a counter electrode/electrode/another
counter electrode layered relationship.
10. The battery cell of claim 9, wherein said electrode further
includes an another film layer having an edge including a first
notch and a third notch with said electrode current collector layer
sandwiched between said electrode film layer and said another film
layer.
11. The battery cell of claim 10, wherein said separator of said
counter electrode is layered adjacent to said electrode film layer,
and said separator of said another counter electrode is layered
adjacent to said electrode another film layer.
12. A battery, comprising: a plurality of cells stacked in relation
to each other, each cell including an electrode having an area
defined by a perimeter including an edge,a counter electrode having
an area defined by a perimeter including an edge, and a separator
having an area defined by a perimeter including an edge, said
separator sandwiched between said electrode and said counter
electrode in a layered relationship with at least portions of said
edges being contiguous, said separator and one of said electrode
and said counter electrode each including a first notch in said
edge exposing a portion of the other of said electrode and said
counter electrode.
13. The battery of claim 12, including a package encasing said
plurality of cells.
14. The battery of claim 13, including a first battery terminal
strip having a first portion disposed inside said package and a
second portion disposed outside said package with said first
portion of said first battery terminal strip in electrical
communication with said exposed portion of the other of said
electrode and said counter electrode of each cell.
15. The battery of claim 14, wherein said separator and the other
of said electrode and said counter electrode each include a second
notch in said edge exposing a portion of said one of said electrode
and said counter electrode.
16. The battery of claim 15, including a second battery terminal
strip having a first portion disposed inside said package and a
second portion disposed outside said package with said first
portion of said second battery terminal strip in electrical
communication with said exposed portion of said one of said
electrode and counter electrode of each cell.
17. The battery of claim 16, wherein said one of said electrode and
said counter electrode is said electrode, and the other of said
electrode and said counter electrode is said counter electrode.
18. The battery of claim 17, wherein said perimeter of said
electrode includes a corner portion defined by said edge and said
second notches.
19. The battery of claim 18, wherein said electrode includes a film
layer and a current collector layer with said current collector
layer including said electrode corner portion and said film layer
including a third notch exposing said electrode corner portion.
20. The battery of claim 19, wherein said electrode corner portion
of each cell is bent to contact said first portion of said second
battery terminal strip.
21. The battery of claim 20, wherein said perimeter of said counter
electrode includes a corner portion defined by said edge and said
first notches.
22. The battery of claim 21, wherein said counter electrode
includes a film layer and a current collector layer with said
current collector layer including said counter electrode corner
portion and said film layer including a fourth notch exposing said
counter electrode corner portion.
23. The battery of claim 22, wherein said counter electrode corner
portion of each cell is bent to contact said first portion of said
first battery terminal strip.
24. The battery of claim 23, wherein said counter electrode
includes said separator with said counter electrode film layer
sandwiched between said counter electrode current collector layer
and said separator in a layered relationship.
25. The battery of claim 24, wherein each cell includes an another
counter electrode similar to said counter electrode with said
another counter electrode stacked in a counter
electrode/electrode/another counter electrode layered
relationship.
26. The battery of claim 25, wherein said electrode further
includes an another film layer having an edge including a first
notch and a third notch with said electrode current collector layer
sandwiched between said electrode film layer and said another film
layer.
27. The battery of claim 26, wherein said separator of said counter
electrode is layered adjacent to said electrode film layer, and
said separator of said another counter electrode is layered
adjacent to said electrode another film layer.
28. The battery of claim 27, wherein said corner portion of said
counter electrode and said another counter electrode of each cell
is bent to contact said first portion of said first battery
terminal strip.
29. A method of producing a battery cell having a plurality of film
layers, a plurality of current collector layers, and at least one
separator layer, each current collector layer including a
predetermined lead portion, comprising the steps of: providing at
least one notch in each layer; and stacking the layers with the
notches arranged with one another to expose the predetermined lead
portion of each current collector layer.
30. The method of claim 29, including the step of laminating the
stacked layers.
31. The method of claim 29, wherein the step of stacking the layers
further includes the steps of providing alignment slots in each
layer, and stacking the layers with the alignment slots arranged
with one another.
32. The method of claim 31, including the step of removing the
alignment slots from each layer.
33. The method of claim 29, wherein the step of providing at least
one notch further includes the steps of providing continuous strips
of film, separator, and current collector, providing at least one
aperture in each strip, and slitting each strip through the
aperture to produce a plurality of identically shaped layers.
Description
FIELD OF THE INVENTION
[0001] This invention relates to a battery cell and a method for
producing the same.
BACKGROUND OF INVENTION
[0002] A battery cell typically includes a separator material
sandwiched between two oppositely-charged electrodes. The
oppositely-charged electrodes are generically referred to as an
electrode and a counter electrode. The term electrode identifies
either a positive (cathodic) electrode or a negative (anodic)
electrode and the term counter electrode identifies the other
electrode.
[0003] A battery bi-cell typically includes at least three
electrodes layered in an electrode/counter electrode/electrode or
counter electrode/electrode/counter electrode relationship.
Separator material can be included in the electrode and/or counter
electrode of the bi-cell.
[0004] Polymer film batteries are commonly constructed from one or
more cells or bi-cells. The bi-cells are normally arranged in a
stack and enclosed in a battery package. A positive terminal strip
and negative terminal strip extend outward from the package. Each
bi-cell typically includes at least one electrode tab and at least
one counter electrode tab connecting the bi-cell to each respective
battery terminal strip. In this manner, the electrode and counter
electrode tabs provide a circuit for charging and discharging the
battery. In most applications, it is desirable to encase the
battery in the smallest possible package. As a result, gathering
the electrode and counter electrode tabs from each bi-cell and
routing such tabs to the respective battery terminal strips within
a small battery package presents difficulties.
[0005] Conventional electrode tab designs used in parallel plate
cell constructions have several shortcomings. Such tab designs
produce a bi-cell having loose internal component tolerances,
inefficient volumetric utilization of the battery package geometry,
and a fragile mechanical structure.
[0006] Further, conventional bi-cell manufacturing methods also
have several shortcomings. Such bi-cell fabrication methods are
complex, wasteful of material, and require a large number of
tolerancing and alignment steps. Accordingly, it would be desirable
to provide a cell design and method of producing the same which
overcome the shortcomings of the prior art.
SUMMARY OF THE INVENTION
[0007] The present invention provides a battery cell including an
electrode having an area defined by a perimeter including an edge,
a counter electrode having an area defined by a perimeter including
an edge, and a separator having an area defined by a perimeter
including an edge. The separator is sandwiched between the
electrode and the counter electrode in a layered relationship with
at least portions of the edges being contiguous. The separator and
one of the electrode and the counter electrode each include a first
notch in the edge exposing a portion of the other of the electrode
and counter electrode.
[0008] The separator and the other of the electrode and the counter
electrode each include a second notch in the edge exposing a
portion of the one of the electrode and the counter electrode.
[0009] A method of producing a battery cell in accordance with the
present invention is also provided. The cell includes a plurality
of film layers, a plurality of current collector layers, and at
least one separator layer. Each current collector layer includes a
predetermined lead portion. The method includes the steps of:
providing at least one notch in each layer, and stacking the layers
with the notches arranged with one another to expose the
predetermined lead portion of each current collector layer.
[0010] These and other objects, features, and advantages will
become apparent from the following description of the preferred
embodiments, claims, and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an exploded, perspective view of a cell, in
accordance with the present invention, having a layered
electrode/separator/counter electrode structure.
[0012] FIG. 2 is a perspective view of the cell of FIG. 1 assembled
in accordance with the present invention.
[0013] FIG. 3 is a partially removed top view of a battery
comprised of a plurality of cells in accordance with the present
invention.
[0014] FIG. 4 is a partially removed side view of the battery of
FIG. 3.
[0015] FIG. 5 is a partially removed front view of the battery of
FIG. 3.
[0016] FIG. 6 is an exploded, perspective view of a bi-cell, in
accordance with the present invention, having a layered counter
electrode/electrode/counter electrode structure.
[0017] FIG. 7 is a perspective view of the bi-cell of FIG. 6
assembled in accordance with the present invention.
[0018] FIG. 8A shows a fragmented portion of a continuous first
strip of film, a fragmented portion of a continuous strip of
current collector, and a fragmented portion of a continuous second
strip of film.
[0019] FIG. 8B shows the fragmented strips of film and current
collector layered upon each other to illustrate a method of
producing a portion of the bi-cell of FIG. 6.
[0020] FIG. 9 shows a fragmented portion of a continuous strip of
material having an alternative notch location.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring to the Figures, wherein like numerals indicate
like or corresponding parts throughout the several views, FIG. 1
shows an exploded, perspective view of a cell 10 in accordance with
the present invention. The cell 10 includes an electrode 12, a
counter electrode 14, and a separator 16. The electrode 12 has an
area, generally indicated by reference numeral 18, defined by a
perimeter 20 including an edge or sidewall 22. The counter
electrode 14 has an area, generally indicated by reference numeral
24, defined by a perimeter 26 including an edge or sidewall 28. The
separator 16 has an area, generally indicated by reference numeral
30, defined by a perimeter 32 including an edge or sidewall 34.
[0022] The electrode 12 includes a film layer 36 and a current
collector or grid layer 38. The counter electrode 14 includes a
film layer 40 and a current collector or grid layer 42. The
electrode film layer 36, the electrode current collector layer 38,
and the separator 16 each include a first notch 44. The counter
electrode film layer 40, the counter electrode current collector
layer 42, and the separator 16 each include a second notch 46. The
first notch 44 is disposed in the edge 22 of the electrode 12 and
the edge 34 of the separator 16. The second notch 46 is disposed in
the edge 28 of the counter electrode 14 and the edge 34 of the
separator 16.
[0023] Preferably, the perimeter 20 of the electrode 12 includes a
corner portion 48, defined in part by the edge 22, which is exposed
by the second notches 46 in the counter electrode 14 and the
separator 16. The electrode corner portion 48 is a part of the
electrode current collector layer 38. Preferably, the perimeter 26
of the counter electrode 14 includes a corner portion 50, defined
in part by the edge 28, which is exposed by the first notches 44 in
the electrode 12 and the separator 16. The counter electrode corner
portion 50 is a part of the counter electrode current collector
layer 42. The electrode film layer 36 includes a third notch 52
exposing the electrode corner portion 48. The counter electrode
film layer 40 includes a fourth notch 54 exposing the counter
electrode corner portion 50.
[0024] In keeping with the present invention, the notches 44, 46,
52, and/or 54 may be disposed in a middle or center of an edge of
one layer to expose a middle or center edge portion of another
layer.
[0025] Typically, the thickness of the cell 10 including the
electrode 12, the separator 16, and the counter electrode 14 is
approximately 0.5 millimeters. Accordingly, the electrode 12, the
counter electrode 14, and the separator 16 shown in FIG. 1 have
been enlarged for illustrative purposes.
[0026] FIG. 2 is a perspective view of the cell 10 assembled in
accordance with the present invention. The separator 16 is
sandwiched between the electrode 12 and the counter electrode 14 in
a layered relationship with at least portions of the edges 22, 28,
and 34 being contiguous. The contiguous area is generally indicated
by reference numeral 56. In other words, the edges 22, 28, and 34,
of the electrode 12, the counter electrode 14, and the separator 16
respectively, overlie/underlie each other in relation to the
horizontal axis H of FIG. 2.
[0027] In FIG. 2, the edges 22, 28, and 34, of the electrode 12,
the counter electrode 14, and the separator 16 respectively, form a
generally or substantially flush surface in relation to the
vertical axis V. However, the edges 22, 28, and 34 may
overhang/underhang each other in relation to the vertical axis V of
FIG. 2 without departing from the scope and spirit of the present
invention.
[0028] The present invention provides a cell 10 having electrode,
counter electrode, and separator layers which are notched to expose
an overlying or underlying surface. In the layered arrangement, the
first notches 44 in the electrode film layer 36, the electrode
current collector layer 38, and the separator 16 and the fourth
notch 54 in the counter electrode film layer 40 align to expose the
corner portion 50 of the overlying counter electrode current
collector layer 42. The second notches 46 in the counter electrode
film layer 40, the counter electrode current collector layer 42,
and the separator 16 and the third notch 52 in the electrode film
layer 36 align to expose the corner portion 48 of the underlying
electrode current collector layer 38.
[0029] Although the electrode 12 and the counter electrode 14 shown
in FIGS. 1 and 2 have a fragmented polygonal shape, one of ordinary
skill in the art will appreciate that the electrode 12 and counter
electrode 14 can take any shape having an edge without departing
from the scope of the present invention.
[0030] The electrode 12 may be a positively-charged electrode, by
definition making the counter electrode 14 a negatively-charged
electrode, or the electrode 12 may be a negatively-charged
electrode, by definition making the counter electrode 14 a
positively-charged electrode.
[0031] FIG. 3 is a partially removed top view of a battery 58
comprised of a plurality of cells 10 in accordance with the present
invention. The components shown in FIG. 3 have been enlarged for
illustrative purposes. The battery 58 includes a package 60 for
housing or encasing the plurality of cells 10. In FIG. 3, a portion
of the top of the package 60 has been removed to show the top
surface of the cells 10, a first battery terminal strip 62, and a
second battery terminal strip 64. The first battery terminal strip
62 includes a first portion 66 disposed inside the package 60 and a
second portion 68 disposed outside the package 60. The second
battery terminal strip 64 includes a first portion 70 disposed
inside the package 60 and a second portion 72 disposed outside the
package 60.
[0032] FIG. 4 is a partially removed side view of the battery 58 of
FIG. 3 with a portion of the side of the package 60 removed to show
three cells 10a, 10b, 10c in a layered or stacked relationship. The
components shown in FIG. 4 have been enlarged for illustrative
purposes. Each cell 10a, 10b, 10c includes a counter electrode
current collector layer, a counter electrode film layer, a
separator, an electrode film layer, and an electrode current
collector layer as previously described. For clarity purposes, only
the counter electrode current collector layers 42a, 42b, 42c of the
cells 10a, 10b, 10c respectively have been labeled in FIG. 4.
Typically, the cells 10a, 10b, 10c are held, fastened, or secured
to one another in the layered relationship with a ultrasonic weld
or other attachment means known in the art.
[0033] In accordance with the present invention, the first portion
66 of the first battery terminal strip 62 is in electrical
communication with the exposed portion of each counter electrode
current collector layer 42a, 42b, 42c. Preferably, the exposed
corner portions 50a, 50c of the outer counter electrode current
collector layers 42a, 42c respectively are bent to contact the
exposed corner portion 50b of the middle counter electrode current
collector layer 42b and/or the first portion 66 of the first
battery terminal strip 62.
[0034] FIG. 5 is a partially removed front view of the battery 58
of FIG. 3 with a portion of the front of the package 60 and the
second portion 68 and 72 of the first and second battery terminal
strips 62 and 64 respectively removed. The components shown in FIG.
5 have been enlarged for illustrative purposes. In accordance with
the present invention, the first portion 70 of the second battery
terminal strip 64 is in electrical communication with the exposed
portion of each electrode current collector layer 38a, 38b, 38c.
Preferably, the corner portion 48a, 48c of the outer electrode
current collector layers 38a, 38c respectively are bent to contact
the exposed corner portion of the middle electrode current
collector layer 38b (hidden behind the second battery terminal
strip 64 in FIG. 5) and/or the first portion 70 of the second
battery terminal strip 64. In this manner, each counter electrode
is electrically connected to the first battery terminal strip 62
and each electrode is electrically connected to the second battery
terminal strip 64 within a cubic-shaped area defined by or
surrounding the stacked cells 10a, 10b, 10c. As a result, the cells
10a, 10b, 10c may be housed or enclosed in a package 60 smaller
than that which is required for cells or bi-cells having known
electrode tabs.
[0035] Alternatively, the corner portions 48a, 48b, 48c, and 50a,
50b, 50c may be bent to contact or meet at a location adjacent to
either of the outer current collector layers 38a or 38c and 42a or
42c respectively.
[0036] The cell 10 has a layered electrode/separator/counter
electrode structure. However, a bi-cell in accordance with the
present invention may include a variety of other layered
arrangements including, but not limited to, a layered counter
electrode/electrode/counter electrode structure.
[0037] FIG. 6 is an exploded, perspective view of a bi-cell 110 in
accordance with the present invention. The bi-cell 110 includes a
first counter electrode 114, an electrode 112, and a second counter
electrode 214.
[0038] The first counter electrode 114 includes a current collector
or grid layer 176, a film layer 178, and a separator layer 180.
Each layer 176, 178, and 180 includes an edge 128 having a second
notch 146. The current collector layer 176 further includes a
corner portion 150. The film layer 178 and the separator layer 180
each include a fourth notch 154 exposing the corner portion
150.
[0039] The electrode 112 includes a first film layer 182, a current
collector or grid layer 184, and a second film layer 186. Each
layer 182, 184, and 186 includes an edge 122 having a first notch
144. The current collector layer 184 further includes a corner
portion 148. The first and second film layers 182 and 186 each
include a third notch 152 exposing the corner portion 148.
[0040] The second counter electrode 214 includes a separator layer
280, a film layer 278, and a current collector or grid layer 276.
Each layer 280, 278, and 276 includes an edge 228 having a second
notch 246. The current collector layer 276 further includes a
corner portion 250. The film layer 278 and the separator layer 280
each include a fourth notch 254 exposing the corner portion
250.
[0041] One of ordinary skill in the art will appreciate that the
order of the electrode and counter electrode layers (i.e. the film
layer, the current collector layer, and the separator layer) may
differ without departing from the scope of the present invention.
The number of layers comprising the electrode and the counter
electrodes may also vary without departing from the scope of the
present invention. A separator layer may be viewed as an individual
layer as shown in FIG. 1, or as part of an electrode or counter
electrode as shown in FIG. 6.
[0042] FIG. 7 is a perspective view of the bi-cell 110 assembled in
accordance with the present invention. The bi-cell 110 is assembled
in a first counter electrode/electrode/second counter electrode
layered relationship. The first notches 144 in the electrode 112
and the fourth notches 154 and 254 in the first and second counter
electrodes 114 and 214 respectively align to expose the corner
portions 150 and 250 of the first and second counter electrodes 114
and 214 respectively. The second notches 146 and 246 in the first
and second counter electrodes 114 and 214 respectively and the
third notches 152 in the electrode 112 align to expose the corner
portion 148 of the electrode 112.
[0043] In accordance with the present invention, a plurality of the
bi-cells 110 may be stacked and encased in a package to form a
battery as previously described for the aforementioned cell 10. In
keeping with the spirit of the present invention, the corner
portions 148 and 150 of the bi-cell 110 may be bent in the manner
previously described for the cell 10. The inventive notches may be
used in a variety of bi-cell structures.
[0044] The location and shape of the notches should be selected to
best facilitate the connection of the exposed portions of each
electrode and counter electrode to the battery terminal strips. The
shape of the notches may be of any geometry with straight, convex,
or concave edges.
[0045] In the aforementioned bi-cell 110 there are three different
types of notches. The three types of notches include (1) a notch in
a current collector layer, hereinafter referred to as a current
collector notch, (2) a notch in a film layer, hereinafter referred
to as a film notch, and (3) a notch in a separator layer,
hereinafter referred to as a separator notches. The size of one
type of notch may differ from the size of another type of notch.
The size of a particular type of notch should be selected in light
of mechanical, electrical, and/or electrochemical considerations.
For example, in the aforementioned bi-cell 110, current collector
notches are preferably larger than film notches, and film notches
are preferably larger than separator notches. In other words, film
notches preferably overhang or extend outwardly from the bi-cell
110 beyond current collector notches, and separator notches
preferably overhang or extend outwardly from the bi-cell 110 beyond
film notches.
[0046] A method of producing a cell or bi-cell in accordance with
the present invention is also provided. The cell or bi-cell
includes a plurality of film layers, a plurality of current
collector layers, and at least one separator layer. These layers
are stacked to form the electrode/separator/ counter electrode cell
arrangement or the counter electrode/electrode/counter electrode
bi-cell arrangement previously described. Each current collector
layer includes a predetermined lead portion previously referred to
as a corner portion. The lead portions are used to electrically
connect the cell or bi-cell to first and second battery terminal
strips.
[0047] The method includes the steps of: providing at least one
notch in each layer, and stacking the layers with the notches
arranged with one another to expose the predetermined lead portion
of each current collector layer. Preferably, the notches are
punched in each layer with a punch tool. Once stacked and aligned,
the layers are laminated.
[0048] In an alternative method, the step of stacking the layers
further includes the steps of: providing alignment slots in each
layer, and stacking the layers with the alignment slots arranged
with one another. After the layers are stacked and aligned, the
alignment slots are preferably removed by slitting or cutting the
alignment slots from each layer.
[0049] In a preferred method, the step of providing at least one
notch further includes the steps of: providing continuous strips of
film, separator, and current collector; providing at least one
aperture in each strip; and slitting each strip through the
aperture to produce a plurality of identically shaped layers.
Preferably, the apertures are punched in each strip with a punch
tool.
[0050] For exemplary purposes and to better understand the method
steps, the method will be described to produce the electrode 112
shown in FIG. 6. FIG. 8A shows a fragmented portion of a continuous
first strip of film 288, a fragmented portion of a continuous strip
of current collector 290, and a fragmented portion of a continuous
second strip of film 292 which may be stacked and slit to produce
the electrode 112. Alternatively, the strips 288, 290, and 292 may
be slit into layers and such layers stacked to produce the
electrode 112.
[0051] Each strip 288, 290, and 292 includes alignment slots 294
and at least one aperture 296. For illustrative purposes, each
strip 288, 290, and 292 has been marked with phantom slit lines
which indicate where each strip 288, 290, and 292 will be slit. The
first strip of film 288 has been marked with phantom slit lines
which bisect the strip of film 288 through the apertures 296 to
produce four identically shaped film layers 182a, 182b, 182c, 182d.
After the first strip of film 288 is slit along the phantom slit
lines, each film layer 182a, 182b, 182c, 182d will include a first
notch 144, an edge 122, and a third notch 152 similar to the first
film layer 182 of the electrode 112 shown in FIG. 6.
[0052] The strip of current collector 290 has been marked with
phantom slit lines which bisect the strip of current collector 290
through the aperture 296 to produce four identically shaped current
collector layers 184a, 184b, 184c, 184d. After the strip of current
collector 290 is slit along the phantom slit lines, each current
collector layer 184a, 184b, 184c, 184d will include a first notch
144, an edge 122, and a corner portion 148 similar to the current
collector layer 184 of the electrode 112 shown in FIG. 6.
[0053] The second strip of film 292 has been marked with phantom
slit lines which bisect the strip of film 292 through the apertures
296 to produce four identically shaped film layers 186a, 186b,
186c, 186d. After the second strip of film 292 is slit along the
phantom slit lines, each film layer 186a, 186b, 186c, 186d will
include a first notch 144, an edge 122, and a third notch 152
similar to the second film layer 186 of the electrode 112 shown in
FIG. 6.
[0054] FIG. 8B shows a stack 298 of the fragmented strips 288, 290,
and 292 layered upon each other in a first film/current
collector/second film relationship. For illustrative purposes, the
stack 298 has been marked with phantom slit lines. The phantom slit
lines identify four identically shaped electrodes 112a, 112b, 112c,
112d comprised of a first film layer 182a, 182b, 182c, 182d, a
current collector layer 184a, 184b, 184c, 184d, and a second film
layer 186a, 186b, 186c, 186d respectively.
[0055] A portion of the first strip of film 288 has been broken
away to show how the third notches 152 in the first and second
strips of film 288 and 292 align to expose the corner portion 148
of the strip of current collector 290 within each electrode 112a,
112b, 112c, 112d. The first notch 144 in the first strip of film
288, the strip of current collector 290, and the second strip of
film 290 align to expose the corner portion of a counter electrode,
not shown.
[0056] Although the strips of film and current collector 288, 290,
292 are illustrated in FIGS. 8A and 8B having a two electrode
width, the strips of film and current collector 288, 290, 292 may
be one electrode, two electrodes, four electrodes, or six
electrodes, etc. wide.
[0057] One of ordinary skill in the art will recognize that this
exemplary process may be repeated to produce a plurality of
electrodes and counter electrodes which may be stacked to produce a
cell or bi-cell in accordance with the present invention.
[0058] One of ordinary skill in the art will recognize that the
claimed method may be used to produce a plurality of cells or
bi-cells which may be stacked and encased in a package and
connected to first and second battery terminal strips to form a
battery as previously described.
[0059] FIG. 9 shows a fragmented portion of a continuous strip of
material 388 having an alternative notch location. The material may
be film, separator, or current collector. For illustrative
purposes, the strip of material 388 has been marked with phantom
slit lines which indicate where the strip 388 will be slit. The
strip of material 388 includes apertures 396 which function
initially as alignment slots 394 and, after the strip 388 is slit,
as notches 344. The phantom slit lines bisect the strip of material
388 through the apertures 396 to produce two identically shaped
material layers 382a and 382b. Although the strip of material 388
is illustrated in FIG. 9 having a one electrode width, the strip
388 may be one electrode, two electrodes, four electrodes, or six
electrodes, etc. wide and still incorporate the alternative notch
location.
[0060] After the strip of material 388 is slit along the phantom
slit lines, each material layer 382a and 382b will include a notch
344 disposed in the middle or center of an edge 322. One of
ordinary skill in the art will recognize that a first layer of
material having a middle edge notch 344 can be aligned to expose a
middle edge portion of an adjacent second layer of material in much
the same manner as a first layer of material having a corner notch
can be aligned to expose a corner portion of an adjacent second
layer of material as described above.
[0061] One of ordinary skill in the art will recognize that the
alternative notch location can be incorporated into the
aforementioned cell 10 and bi-cell 110 designs. One of ordinary
skill in the art will also recognize that the aforementioned method
can be used to produce a cell having the alternative notch
location.
* * * * *