Battery module and method of making a battery

A battery module includes a number of electrically connected electrochemical cells. In a preferred embodiment, the battery includes multi-cell batteries in which electrodes are separated from different potential electrodes by a layer of polymer electrolyte. The battery module is formed from a number of multi-cell batteries stacked on top of one another, the electrodes of each multi-cell being electrically connected to one another, and the different potential electrodes of each multi-cell being electrically connected to one another so that a battery module having desired power characteristics is formed. The battery module includes electrically conductive spacers for electrically connecting tabs on the electrodes to tabs on other electrodes and tabs on the different potential electrodes to tabs on other different potential electrodes and for preventing damage to the tabs or the electrodes or different potential electrodes from bending the tabs excessively.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to batteries and, more particularly, the 
present invention relates to batteries of the type having a polymer 
electrolyte. 
2. State of the Art 
In recent years, individuals in the battery art have begun to understand 
the advantages of manufacturing batteries that have polymer electrolytes 
and sheet-like cathodes and anodes. The advantages include lower battery 
weight than batteries that employ liquid electrolytes, longer service 
life, relatively high power densities, relatively high specific energies, 
and the elimination of danger due to the spillage of acidic liquid 
electrolytes. 
In fabricating batteries, it is generally necessary to connect an anode to 
an anode current collector and a cathode to a cathode current collector so 
that electric energy can be drawn from the battery by an external load. In 
multi-cell batteries, current collectors are generally connected to each 
anode and each cathode, and the current collectors connected to each anode 
are electrically connected together and the current collectors connected 
to each cathode are electrically connected together. 
In batteries of the type that have a thin polymer electrolyte and 
sheet-like anode and cathode layers, it is common that a relatively large 
number of individual cells form a battery. The connection of separate 
current collectors to the individual anode and cathode layers of the cells 
can be quite troublesome. One problem is that relatively large numbers of 
current collectors must be provided. Further, means for attaching the 
current collectors to the anodes and cathodes must be provided. Further 
still, as the anode and cathode layers are generally quite thin, the 
current collectors and the means for attaching the current collectors must 
not be overly large or obtrusive such that they interfere with one another 
or with the formation of the battery. 
SUMMARY OF THE INVENTION 
The present invention, generally speaking, provides a battery that uses a 
polymer electrolyte in lieu of a liquid electrolyte to attain desired 
operating characteristics in a small, light-weight battery. 
In accordance with one aspect of the present invention, an electrochemical 
cell includes a first electrode, a second electrode, and electrolyte 
material. The first electrode includes means for first electrode current 
collection, the first electrode current collection means being formed from 
a first conductive sheet, and a layer of first electrode material. The 
second electrode is of a different potential than that of the first 
electrode and includes means for second electrode current collection, the 
second electrode current collection means being formed from a second 
conductive sheet, and a layer of second electrode material. An electrolyte 
is coated on one of the first or second electrode materials and contacts 
with the other of the first or second electrode materials. An outer 
periphery of the first electrode is larger than an outer periphery of the 
second electrode such that substantially all of the outer periphery of the 
second electrode is bounded by the outer periphery of the first electrode. 
In accordance with another aspect of the present invention, a multi-cell 
battery module includes a first electrode, a second electrode, a third 
electrode, and electrolyte material. The first electrode includes means 
for first electrode current collection, the first electrode current 
collection means being formed from a first conductive sheet, and a layer 
of first electrode material contacting a surface of the first conductive 
sheet. The second electrode includes means for second electrode current 
collection, the second electrode current collection means being formed 
from a second conductive sheet, and first and second layers of second 
electrode material contacting first and second surfaces of the second 
conductive sheet, the second electrode material is of a different 
potential than that of the first electrode material. The third electrode 
includes means for third electrode current collection, the third electrode 
current collection means being formed from a third conductive sheet, and a 
layer of third electrode material contacting a surface of the third 
conductive sheet, the third electrode material having the same potential 
as the first electrode material. Electrolyte material is disposed between 
the first and the second electrodes and disposed between the second and 
the third electrodes. 
In accordance with still another aspect of the present invention, a battery 
module stack includes a plurality of multi-cell battery modules stacked on 
top of one another. Each multi-cell battery module comprises a first 
electrode including a first electrode tab extending from the first 
electrode, a second electrode including a second electrode tab extending 
from the second electrode, and a third electrode including a third 
electrode tab extending from the third electrode. The first electrode tab, 
the second electrode tab, and the third electrode tab extend from the 
multi-cell battery module such that the first electrode tab and the third 
electrode tab do not contact or electrically interfere with the second 
electrode tab. Means are provided for electrical connection of the first 
and third electrode tabs of the plurality of multi-cell battery modules. 
Means are provided for electrical connection of the second electrode tabs 
of the plurality of multi-cell battery modules. 
In accordance with still another aspect of the present invention, a method 
of making a battery module stack is disclosed. One or more first and one 
or more second electrodes are stacked on top of one another such that 
first electrode material of the first electrodes faces second electrode 
material of the second electrodes and such that a layer of electrolyte 
material on the first electrodes separates the first electrode material 
and the second material. The first electrodes have first tabs. The second 
electrodes have second tabs. The first tabs are electrically connected. 
The second tabs are electrically connected.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
With reference to FIGS. 1 and 2, a multi-cell battery 21 includes a first 
electrode 31, a second electrode 41, and a third electrode 51. The first 
electrode 31 and the third electrode 51 are of the same potential as each 
other, and the second electrode 41 is of an different, or second, 
potential. The first electrode 31 faces a first layer of second potential 
electrode material 43 on the second electrode 41 to form a first 
electrochemical cell 22. The third electrode 51 faces a second layer of 
second potential electrode material 45 on the second electrode 41 to form 
a second electrochemical cell 23. The first and second electrochemical 
cells thus form a "multi-cell" battery. U.S. Pat. No. 4,925,751 to Shackle 
et al. describes certain anode, cathode, and polymer electrolyte materials 
useful in forming the multi-cell battery and is incorporated by reference 
only to the extent that it describes such materials. 
In a preferred embodiment, the multi-cell battery 21 includes two 
electrochemical cells 22, 23 and is referred to as a "bicell" battery. For 
the remainder of this description, the multi-cell battery 21 will be 
referred to as a bicell battery in accordance with the preferred 
embodiment. However, it is understood that any number of electrochemical 
cells 22, 23 may be stacked on top of one another in the manner described 
herein to form a battery 21 with any number of individual cells. 
In forming the first and third electrodes 31, 51, a layer of electrode 
material 33, 53 is applied in a predetermined thickness onto one surface 
34, 54 of a conductive sheet 32, 52. A polymer electrolyte 35, 55 is then 
applied, in a layer of a predetermined thickness onto the layer of 
electrode material 33, 53. 
The conductive sheets 32, 52 of the first and third electrodes 31, 51 are 
preferably formed from a web or sheet of conductive material. In a 
presently preferred embodiment, the conductive sheets 32, 52 are formed 
from a nickel or copper web or sheet. Electrode material for forming the 
layers of electrode material 33, 53 is applied to the web or sheet, such 
as by being extruded, and has a consistent, desired thickness. Polymer 
electrolyte material for forming the layers of electrolyte 35, 55 is 
applied to the electrode material, such as by being extruded, and has a 
consistent, desired thickness. The conductive web or sheet having layers 
of electrode material and electrolyte material is cut into desired shapes 
to form the first and third electrodes 31, 51. The electrode material 33, 
53 is preferably a cathode material selected from the group of materials 
suited for storing ions released from an anode, with a vanadium oxide, 
V.sub.6 O.sub.13 or V.sub.3 O.sub.8, material being preferred. 
The second electrode 41 includes a conductive sheet 42. A first layer 43 of 
electrode material, having an different potential to that of the layers of 
electrode material 33, 53 on the first and third electrodes 31, 51, is 
applied to a first side 44 of the conductive sheet 42. A second layer 45 
of electrode material, also having an different potential to that of the 
layers of electrode material 33, 53 on the first and third electrodes 31, 
51, is applied to a second side 46 of the conductive sheet 42. 
As with the conductive sheets 32, 52, the conductive sheet 42 is preferably 
formed from a continuous conductive material, such as a nickel or copper 
web or sheet. The conductive sheet 42 is preferably cut in a desired shape 
from the web or sheet. The first and second layers of different, or 
second, potential electrode material 43, 45 are preferably an anode 
material, a lithium anode material being preferred. The first and second 
layers of different, or second, potential material 43, 45 are deposited to 
a desired thickness on the web for forming the conductive sheet 42. 
In forming the bicell battery 21, the first electrode 31 and the second 
electrode 41 are position relative to one another such that the first 
layer of different, or second, potential electrode material 43 contacts 
the layer of electrolyte material 35 on the first electrode 31. The third 
electrode 51 and the second electrode 41 are positioned relative to one 
another such that the second layer of different, or second, potential 
electrode material 45 contacts the layer of electrolyte material 55 on the 
third electrode 51. 
Substantially all of the surface area of the second electrode 41 is within 
the boundaries of the surface area of the first and third electrodes 31, 
51 to prevent inadvertent contact between the edge 47 of the second 
electrode and the edges 36, 56 of the first and third electrodes. Contact 
between the edge 47 of the second electrode 41 and the edges 36, 56 of the 
first and third electrodes 31, 51 might result in shorting of the bicell 
battery 21. 
To prevent inadvertent puncturing of the layers of electrolyte material 35, 
55 on the first and third electrodes 31, 51 by the edge 47 or corners 48 
of the second electrode 41, which might also result in shorting of the 
bicell battery 21, a means 71 for masking the edge and corners of the 
second electrode is provided. The masking means 71 frames the edge 47 and 
corners 48 of the second electrode 41 while allowing contact between the 
substantially all of the surface area of the first and second layers of 
different, second, potential electrode material 43, 45 and the electrode 
material 33, 53 of the first and third electrodes 31, 51, respectively. A 
preferred material for forming the masking means 71 is a polymeric 
material such as a porous polypropylene. The masking means 71 is generally 
quite thin, and only insignificant surface distortion of the first, 
second, or third electrodes 31, 41, or 51 occurs to accommodate the 
thickness of the masking means when the electrode surfaces contact with 
one another. 
The first electrode 31 is provided with a conductive first electrode tab 37 
extending from the first conductive sheet 32 to facilitate making an 
electrical connection between the first conductive sheet and an external 
load or power source. The first electrode tab 37 is preferably a portion 
of the first conductive sheet 32 that extends beyond a portion of the 
first conductive sheet to which electrode material 33 is applied. The 
second electrode 41 is provided with a second electrode tab 49 and the 
third electrode 51 is provided with a third electrode tab 57 in a similar 
manner. 
The tabs 37, 49, 57 of the first, second, and third electrodes 31, 41, 51 
are preferably portions of the conductive sheets 32, 42, 52 that are not 
coated with electrode material 33, 53 or different, or second, potential 
material 43, 45. As seen in FIGS. 3, 4, 5, and 7, the first electrode tab 
37 and the third electrode tab 57 preferably extend from the first 
electrode 31 and the third electrode 51 such that, when the first 
electrode and the third electrode are positioned around the second 
electrode 41 to form a bicell battery 21, the first electrode tab and the 
third electrode tab are aligned substantially adjacent to one another over 
the height of the bicell battery. As seen in FIGS. 4 and 7, the aligned 
first electrode tab 37 and third electrode tab 57 are electrically 
connected to one another by being bent to contact one another. As seen in 
FIG. 6, the aligned second electrode tabs 49 are electrically connected to 
one another by being bent to contact one another. 
As seen in FIGS. 3 and 4, a desired number of bicell batteries 21 are 
stacked, one on top of another, to form a group 25 of bicell batteries. As 
seen in FIGS. 3 and 5, the second electrode tabs 49 extend from the second 
electrodes 41 such that, when the first electrodes and the third 
electrodes 51 are positioned around the second electrodes to form bicell 
batteries 21, the second electrode tabs are offset from and do not contact 
or otherwise electrically interfere with the first or third electrode tabs 
37, 57. The second electrode tabs 49 of each of the second electrodes 41 
are aligned relative to one another over the height of the battery along a 
single line offset from a line extending through the first and third 
electrode tabs 37, 57. The aligned second electrode tabs 49 are 
electrically connected by being bent to contact one another. When the 
plurality of bicell batteries 21 are stacked on top of one another, the 
non-coated side 59 of the third conductive sheet 52 of the third electrode 
51 contacts with, and is thereby electrically connected to, the non-coated 
side 39 of the first conductive sheet 32 of a subsequent first electrode 
31. 
As noted above, in order for the second electrode tabs 49 of the plurality 
of bicell batteries 21 to contact one another, and in order for the first 
electrode tabs 37 and the third electrode tabs 57 of the plurality of 
bicell batteries to contact one another, because of the thickness of the 
various layers of material, some of the first electrode tabs, the second 
electrode tabs, and the third electrode tabs are bent to contact other 
tabs. As seen, for example, in FIG. 4, in a group 25 of bicell batteries 
21, certain first and third electrode tabs 37, 57, generally on the 
outside of the group, are bent more than others. Similarly, as seen in 
FIG. 6, certain second electrode tabs 49, generally on the outside of the 
group 25, are bent more than others in endeavoring to electrically connect 
the second electrode tabs to one another. 
Because the anode and cathode materials applied to the conductive sheets 
32, 42, and 52 may tend, under some conditions, to de-laminate from the 
conductive sheets, and because of the possibility of breakage of electrode 
tabs 37, 49, 57, it is desirable to minimize the degree to which the 
electrode tabs are bent. Minimizing bending of the tabs 37, 49, 57 
minimizes the danger of breakage of electrode tabs. To minimize the need 
to bend tabs 37, 49, 57, a group 25 preferably includes only approximately 
six or seven bicell batteries 21 so that the tabs in one group may be 
electrically connected to one another, and the bicell batteries are 
aligned with one another, in such a manner that no tab need be excessively 
bent to contact another tab in the group. By maintaining the number of 
bicell batteries 21 in a group 25 at approximately six or seven, it is not 
generally necessary to excessively bend any individual electrode tab 37, 
49, 57 to electrically connect the tab with the other tabs in the group. 
In addition to maintaining the size of a group 25 to a reasonable number of 
bicell batteries 21, conductive spacer means 100, seen in FIG. 5, are 
provided for aligning and electrically connecting the plurality of second 
electrode tabs 49 and for aligning and electrically connecting the 
plurality of first electrode tabs 37 and third electrode tabs 57 of one or 
more groups of bicell batteries in such a manner as to minimize any 
bending of the tabs 37, 49, 57. The spacer means 100 includes means for 
aligning and electrically connecting a desired number of first electrode 
tabs 37 and third electrode tabs 57, preferably an electrode spacer bar 
assembly 101, and means for aligning and electrically connecting a desired 
number of second electrode tabs 49 of groups 25 of bicell batteries 21, 
preferably an different, or second, potential electrode spacer bar 
assembly 111. 
As seen in FIGS. 4 and 7, bending of the first electrode tabs 37 and the 
third electrode tabs 57 of a group 25 of bicell batteries 21 is minimized 
and the tabs are electrically connected to one another by being clamped 
together in the electrode spacer bar assembly 101. As seen in FIGS. 5 and 
7, the electrode spacer bar assembly 101 includes a desired number of 
electrode spacers 102, an electrode terminal 103 for electrically 
connecting the electrode spacer bar assembly to an outside load or power 
source, a pair of electrode spacer bar assembly end plates 104, and a 
fastening means such as shafts 105 with increased diameter caps or ends 
105' for holding the electrode spacer bar assembly together. The ends 105' 
may be part of the shaft 105 or separate elements secured thereto. For 
example, the shaft 105 may be a rivet that is deformed to form each of the 
ends 105', or the shaft may be provided with any other suitable, separate 
fastening means, such as a bolt and nut arrangement, or other suitable 
fastener. The electrode spacer bar assembly end plates 104 sandwich the 
electrode spacers 102 and the electrode terminal 103 when the shaft 105 
with ends 105' fastens the electrode spacer bar assembly 101 together 
around the tabs 37, 57. 
As seen in FIGS. 4, 5, and 7, the first electrode tabs 37 and the third 
electrode tabs 57 of each group 25 of bicell batteries 21 are clamped 
between either two electrode spacers 102, an electrode spacer and an 
electrode terminal 103, an electrode spacer and an electrode spacer bar 
assembly end plate 104, or an electrode terminal and an electrode spacer 
bar assembly end plate. The electrode spacers 102, the electrode terminal 
103, and the electrode spacer bar assembly end plates 104, as well as the 
first and third electrode tabs 37, 57 of groups 25 of bicell batteries 21, 
are fastened together by the shaft 105, seen in FIGS. 5 and 7, and its 
ends 105'. The thicknesses of individual ones of the electrode spacer bars 
102, electrode terminals 103, and electrode spacer bar assembly end plates 
104, and the number of bicell batteries 21 constituting a group 25, are 
preferably selected such that any bending of the first electrode tabs 37 
or third electrode tabs 57 for being clamped by the electrode spacer bar 
assembly 101 presents little danger of delamination of electrode material 
33, 53 or of breakage of electrode tabs. 
As seen in FIGS. 5 and 6, an different, or second, potential electrode 
spacer bar assembly 111, including different, or second, potential 
electrode spacers 112 and an different, or second, potential electrode 
terminal 113 fastened between two different, or second, potential 
electrode spacer bar assembly end plates 114 by fastening means such as 
shafts 115 with increased diameter caps or ends 115', seen in FIG. 5, is 
provided for electrically connecting the second electrode tabs 49 of 
groups 25 of bicell batteries 21 in the same or a similar fashion as the 
electrode spacer bar assembly 101 electrically connects the first and 
third electrode tabs 37, 57. As noted above, the second electrode tabs 49 
are offset from and do not contact or otherwise electrically interfere 
with the first and third electrode tabs 37, 57. The electrode spacer bar 
assembly 101 is also offset from and does not contact or otherwise 
electrically interfere with the second electrode tabs 49. Similarly, the 
different, or second, potential electrode spacer bar assembly 111 is 
offset from and does not contact or otherwise electrically interfere with 
the first and third electrode tabs 37, 57 or the electrode spacer bar 
assembly 101. 
Similar to the elements of the electrode spacer bar assembly 101, the 
thickness of individual ones of the different, or second, potential 
electrode spacer bars 112, different, or second, potential electrode 
terminals 113, and different, or second, potential electrode spacer bar 
assembly end plates 114, and the number of bicell batteries 21 
constituting a group 25, are preferably selected such that any bending of 
the second electrode tabs 49 for being clamped by the different, or 
second, potential electrode spacer bar assembly 111 presents little danger 
of delamination of different, or second, potential electrode material 43, 
45 or breakage of second electrode tabs 49. In a preferred embodiment, the 
same number of electrode spacer bars 102 are used as the number of 
different, or second, potential electrode spacer bars 112. However, if 
desired, different numbers of electrode spacer bars 102 than different, or 
second, potential electrode spacer bars 112 may be used, and different 
numbers of second electrode tabs 49 may be clamped between different, or 
second, potential electrode spacer bars, different, or second, potential 
electrode terminals 113, and different, or second, potential electrode 
spacer bar assembly end plates 114 than first and third electrodes that 
are clamped between corresponding members of the electrode spacer bar 
assembly 101. 
In addition to clamping together the first and third electrode tabs 37, 57 
of groups of bicell batteries and clamping together the second electrode 
tabs 49 of groups 25 of bicell batteries, the electrode spacer bar 
assembly 101 and the different, or second, potential electrode spacer bar 
assembly 111 facilitate proper alignment of the tabs. Considering, first, 
the alignment of the first and third electrode tabs 37, 57, as seen in 
FIGS. 1 and 3, the first electrode tabs are preferably formed with holes 
38 and the third electrode tabs are preferably formed with holes 58. The 
holes 38 and 58 of a plurality of bicell batteries 21 are aligned relative 
to one another by being stacked on top of one another over the shafts 105. 
Similarly, as seen in FIG. 5, the electrode spacer bars 102 are preferably 
formed with holes 106, the electrode terminal is preferably formed with 
holes 107, and the electrode spacer bar assembly end plates 104 are 
preferably formed with holes 108 to facilitate being aligned relative to 
one another, as well as to the first and third electrode tabs 37, 57, by 
being stacked over the shafts 105. 
Similarly, as seen in FIGS. 1 and 3, the second electrode tabs 49 are 
preferably formed with holes 50. The holes 50 of a plurality of bicell 
batteries 21 are aligned relative to one another by being stacked on top 
of one another over the shafts 115. As seen in FIG. 5, the different, or 
second, potential electrode spacer bars 112 are preferably formed with 
holes 116, the different, or second, potential electrode terminal 113 is 
preferably formed with holes 117, and the different, or second, potential 
electrode spacer bar end plates 114 are preferably formed with holes 118 
to facilitate being aligned relative to one another, as well as to the 
second electrode tabs 49, by being stacked over the shafts 115. The 
electrode terminal 103 is preferably formed with additional holes 109 and 
the different, or second, potential electrode terminal 113 is preferably 
formed with additional holes 119 to facilitate making external connections 
with power sources or loads. 
The thickness of the electrode spacer bar assembly 101 plus the thickness 
of a plurality of clamped first electrode tabs 37 and third electrode tabs 
57 of a plurality of bicell batteries 21 is preferably substantially the 
same as the thickness of the bicell batteries. Similarly, the thickness of 
the different, or second potential electrode spacer bar assembly 111 plus 
the thickness of a plurality of clamped second electrode tabs 49 of the 
plurality bicell batteries 21 is preferably substantially the same as the 
thickness of the plurality of bicell batteries. It is preferred to form 
the electrode spacer bar assembly 101 and the different, or second, 
potential electrode spacer bar assembly 111 in such thicknesses so that a 
stack 26 of groups 25 of a plurality of bicell batteries 21 and the spacer 
means 100 is a substantially constant thickness. 
The stack 26 of bicell batteries 21 may be assembled by inserting fastening 
means such as shafts 105 through holes 108 in an electrode spacer bar 
assembly end plate 104 and inserting fastening means such as shafts 115 
through holes 118 in an different, or second, potential electrode spacer 
bar assembly end plate 114. First electrodes 31, second electrodes 41, and 
third electrodes 51 are then layered on top of one another, the shafts 105 
are inserted through the holes 38, 58, and the shafts 115 are inserted 
through the holes 50 until a desired number of bicell batteries 21 form a 
group 25. If desired, the masking means 71 may be provided between the 
first electrode 31 and the second electrode 41 and between the second 
electrode and the third electrode 51. 
The shafts 105 are then inserted through the holes 106 of an electrode 
spacer bar 102 so that the electrode spacer bar and the electrode spacer 
bar assembly end plate 104 sandwich the first electrode tabs 37 and the 
third electrode tabs 57 of the group 25 of bicell batteries 21. The shafts 
115 are inserted through the holes 116 of an different, or second, 
potential electrode spacer bar 112 so that the different, or second, 
potential electrode spacer bar and the different, or second, potential 
spacer bar assembly end plate 114 sandwich the second electrode tabs 49 of 
the group 25 of bicell batteries 21. Additional groups 25 of bicell 
batteries 21 of the same or varying numbers of bicell batteries and 
additional spacer bars 102, 112 may be attached to the shafts 105, 115 in 
the same fashion. 
The shafts 105, 115 are inserted through holes 107, 117, respectively, of 
the electrode terminal 103 and the different, or second, potential 
electrode terminal 113. Normally, the electrode terminal 103 and the 
different, or second potential electrode terminal 113 are applied to the 
assembly so that they project from a center of the stack 26 of bicell 
batteries 21. After a desired number of groups 25 of bicell batteries 21, 
spacer bars 102, 112, and terminals 103, 113 are connected, the shafts 105 
are inserted through the holes 108 in another electrode spacer bar 
assembly end plate 104, the shafts 115 are inserted through the holes 118 
in another different or second, potential electrode spacer bar assembly 
end plate 114. The shafts 105, 115 are secured to the stacks 26 by the 
ends 105', 115' and fasten together the electrode spacer bar assembly 101, 
the first electrodes 31, and the third electrodes 51 and fasten together 
the different, or second, potential electrode spacer bar assembly 111 and 
the second electrodes 41 such as by deforming the shafts to form increased 
diameter ends or by attaching nuts or caps to threaded portions of the 
shafts to form ends. 
As shown in FIGS. 6-8, more than one stack 26 may be electrically connected 
to form a multi-stack battery 10 having more power than a single stack. 
Multiple stacks 26 are stacked on top of one another to such that an 
electrode spacer bar assembly endplate 104 of a first stack contacts an 
electrode spacer bar assembly endplate of a subsequent stack and an 
different, or second, potential electrode spacer bar assembly endplate 114 
of the first stack contacts an different, or second, potential electrode 
spacer bar assembly endplate 114 of the subsequent stack, thereby 
electrically connecting the stacks. Wiring or other suitable means for 
electrically connecting the terminals 103, 113 of multiple stacks 26 of 
bicell batteries 21 may also be provided to electrically connect the 
stacks. 
As seen in FIGS. 6, 7, and 8, after a stack 26 of bicell batteries 21, or a 
multi-stack battery 10, has been formed as described above, a means 120 
for enclosing the stack is provided around the stack. Preferably, the 
enclosing means 120 includes a non-conductive, heat-sealable plastic wrap 
material that is wrapped around the stack 26 and is heat-sealed around the 
stack such that the stack is insulated. The enclosing means 120 may also 
be used to secure the various components of the stack 26 together. At 
least a portion of an electrode terminal 103 and a portion of an 
different, or second, potential electrode terminal 113 extend out of the 
enclosing means 120(which is sealed at its edges). Alternatively, 
conductive means such as wiring (not shown) for electrically connecting 
the terminals 103, 113 extends from the enclosing means 120, and the 
terminals 103, 113 are sealed inside the enclosing means. Sealing means 
125, such as a hot-melt adhesive, is applied around edges 121 of the 
wrapped material around the electrode terminals 103 and the different, or 
second, potential electrode terminals 113, or conductive means (not shown) 
connecting those terminals, to ensure that the stack 26 is well sealed. 
The stack 26 is manufactured by a method wherein the first electrode 31, 
the second electrode 41, and the third electrode 51 are stacked on top of 
one another such that the electrode material 33, 53 of the first and third 
electrodes faces the different, or second, potential electrode material 
43, 45 on the second electrode. The first electrode 31, the second 
electrode 41, and the third electrode 51 are stacked such that the 
electrolyte material layer 35 on the first electrode separates the 
electrode material layer 33 on the first electrode and the layer of 
different, or second, potential electrode material 43 on the first surface 
44 of the conductive sheet 42 and such that the electrolyte material layer 
55 on the third electrode separates the electrode material layer 53 on the 
third electrode and the layer of different, or second, potential electrode 
material 45 on the second surface 46 of the conductive sheet. The first 
electrode tabs 31 and the third electrode tabs 57 are electrically 
connected to one another by the electrode spacer bar assembly 101. The 
second electrode tabs 49 are electrically connected to one another by the 
different, or second, potential electrode spacer bar assembly 111. 
The first and third electrode tabs 37, 57 are clamped between sets of 
electrode spacer bars 102, electrode terminals 103, or electrode spacer 
bar assembly endplates 104, and the second electrode tabs 49 are clamped 
between sets of different, or second, potential electrode spacer bars 112, 
different, or second, potential electrode terminals 113, or different, or 
second potential electrode spacer bar assembly endplates 114. Preferably, 
the first and third electrode tabs 37, 57 are fastened in position 
relative to the electrode spacers 102, the electrode terminal 103, and the 
electrode spacer bar assembly end plates 104 with shafts 105 having ends 
105'; and, preferably, the second electrode tabs 49 are fastened in 
position relative to the different, or second potential electrode spacers 
112, the different, or second potential electrode terminals 113, and the 
different, or second, potential electrode spacer bar assembly end plates 
114 with shafts 115 having ends 115'. Holes 38, 58, 106, 107, and 108 are 
preferably formed in, respectively, the first electrode tabs 37, the third 
electrode tabs 57, the electrode spacer bars 102, the electrode terminal 
103, and the electrode spacer bar assembly end plates 104, and holes 50, 
116, 117, and 118 are preferably formed in, respectively, the second 
electrode tabs 49, the different, or second, potential electrode spacer 
bar 112, the different, or second, potential electrode terminal 113, and 
the different, or second, potential electrode spacer bar assembly end 
plates 114 before fastening with shafts 105, 115. 
The various components of the stack 26 with the above-noted holes may be 
stacked on top of another in such a manner that the shafts 105, 115 act as 
a guide for properly aligning the components. Alternatively, the shafts 
105, 115 fasten together components that have been pre-aligned, such as by 
stacking the components in a form of a shape corresponding to the shape of 
the components, and form the above-noted holes while the fastening is 
taking place. 
The bicell batteries 21 have thus far been described with reference to 
first and third electrodes 31, 51 including polymer electrolyte layers 35, 
55 on electrode material layers 33, 53. It is, however, possible to form 
polymer electrolyte layers on the different, or second, potential 
electrode material layers 43, 45 on the opposite polarity electrode 41, 
instead of on the electrode material layers 33, 53. 
The bicell batteries 21 have also, thus far, been described with reference 
to first and third electrodes 31, 51 being larger in surface area than a 
second electrode 41, such that substantially all of the surface area of 
the second electrode is bound by the first and third electrodes. It is, 
however, possible to form second electrodes 41 that are larger in surface 
area than first and third electrodes 31, 51, such that substantially all 
of the surface area of the first and third electrodes is bounded by the 
second electrodes. Similarly, masking means 71 may be provided around the 
edges of the first and third electrodes 31, 51 to avoid contact of the 
electrode material 33, 53 with the different, or second, potential 
electrode material 43, 45. 
Further, the bicell batteries 21 have been described, thus far, with 
reference to first and third electrode tabs 37, 57 that are aligned with 
each other such that they are clamped together in an electrode spacer bar 
assembly 101. It is also possible to form first and third electrode tabs 
37, 57 that do not align with one another in a bicell battery 21. One 
electrode spacer bar assembly may be provided for clamping and 
electrically connecting all of the first electrode tabs 37 and another 
electrode spacer bar assembly may be provided for clamping and 
electrically connecting all of the third electrode tabs 57. The two 
electrode spacer bar assemblies may then be electrically connected to one 
another. 
The foregoing has described the principles, preferred embodiments and modes 
of operation of the present invention. However, the invention should not 
be construed as limited to the particular embodiments discussed. Instead, 
the above-described embodiments should be regarded as illustrative rather 
than restrictive, and it should be appreciated that variations may be made 
in those embodiments by workers skilled in the art without departing from 
the scope of present invention as defined by the following claims.