Note: Descriptions are shown in the official language in which they were submitted.
10~7 ~ A75-34
BACKGROUND OF THE INVENTION
This invention relates generally to secondary storage
batteries and particularly to lead-acid type storage batteries
having through the partition intercell connections.
In recent years, the lead-acid storage battery industry
has developed an intercell connection in ba~teries in which
electrical connection between adjacent battery plate elements
in battery cells is made by electrically joining the elements
through the battery partition walls. This type of intercell
connection is seen in U.S. Patents No. 3,793,086 issued February
19, 1974 to Badger; 3,869,316 issued March 4, 1975 to Matter;
3,313,658 issued April 11, 1967 to Sabatino et al and 3,897,269
issued July 29, 1975 to Sabatino et àl, both assigned to the
assignee of the present invention. The intercell connections
described in the aforementioned patents basically relate to
automotive type lead-acid batteries having a plurality of cells
with each cell including a plurality of alternating negative and
positive battery plates. The negative plates in each cell have
protruding lugs which are joined together by electrically con-
ductive connecting straps. Similarly, the positive plates in
each cell have lugs which are joined by straps as well. The
straps connecting the positive and negative plates are provided
with an upstanding lug. The upstanding lug from a group of
positive or negative plates in one cell is aligned with the
upstanding lug on the group of opposite polarity plates in the
adjacent cell. ~1 aperture is provided in the cell partition
wall and the lugs are joined together through the partition wall
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by welding to provide a connection through the aperture. The
types of batteries with which these patents are concerned are
adapted for use in automotive vehicles to perform such functions
as providing starting, lighting and ignition. Conventionally,
such batteries include a minimum number of seven or more plates
in each cell. As a practical necessity within the cells, straps
must be provided to couple the lugs of similar polarity plates.
While Canadian Patent No. 873,522 issued June 15, 1971 to Matter
proports to show an intercell connection of a plurality of
plates by directly welding a plurality of lugs together, it
has been applicant's experience that such a construction is
impractical for mass production of batteries. This is because
the welding technique utilized to join the lu~s relies upon
resistance welding whereby high resistance between juxtapositioned
lead parts results in generation of sufficient heat to melt the
adjoining lead pieces and fluidize the lead to cause fusion. In
the case of a plurality of parts having two or more interfacing
surface8, fusion does not reliably always take place at all
interfaces whereby defective connections could result. It has
been found that the most desirable intercell welding thus requires
no more than two surfaces to be joined.
Conventional lead-acid automotive type batteries are ~lso
of an excessive capacity from that required to start small engines
such as used in riding mowers, snow blowers, and the like. Such
batteries generally require a fewer number of plates than are
normally contained in an automotive type battery in order to
provide adequate service.
106~780
` SUMMARY OF THE INVENTION
.
It is an object of the present invention to provide a
secondary storage battery and method of manufacture which
is easily adaptable to mass production techniques.
A further object of the invention is to provide a
secondary storage battery and method of making the same
which involves less material than that used in
conventional techniques.
Other objects and advantages of the present invention
will become apparent from a description of the preferred
embodiments which follows.
Basically the invention comprises a storage battery
and method of making the same which involves providing a
single positive and negative battery plate which are
folded with an interspersed nonconductive separator sheet,
each plate is provided with a protruding lug and a folded
pair of plates and separators comprises a battery
element. The lug of each plate is joined to the lug of an
opposite polarity plate in an adjacent battery cell by
forming a sealed fusion connection through an aperture in
the partition wall. The end most plates of the battery
are coupled to positive and negative battery terminals by
a similar welded joint through the battery case walls.
Thus, the storage battery of this invention comprises:
a battery case having a bottom and four side walls, at
least one partition dividing the case into two or more
cell compartments and a cover; a battery element disposed
within each cell compartment, each element comprising a
single fold positive polarity battery plate and a single
fold negative polarity battery plate, each of said plates
having a vertical median bighted surface at the fold and
two integral substantially parallel pasted spaced apart
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frame members extending from the bight to provide a
bifurcated plate configuration with each frame member
providing a pair of pasted surfaces, each plate having a
conductive lug proximate the bighted surface, said plate
frame members being interleaved whereby one of the
positive plate frame members extends into the bight of the
negative polarity plate toward the negative bighted
surface spatially separated from the negative f~ame- -
members pasted surfaces, and an N-shaped nonconductive
separator sheet providing separator surfaces disposed
between all adjoining surfaces of said plates; the
conductive lug of each plate being joined to the con-
ductive lug of an opposite polarity plate in the adjoining
cell by a connection through the intervening partition,
and the unjoined conductive lugs of the end-~ost cells
being coupled to the terminal posts extending outside the
battery case; and means for venting the interior of each
cell to the outside of the battery case.
The method of the invention comprises:
providing a battery case having bottom and side walls
and at least one partition dividing the interior of the
case into at least two separate compartments; providing a
lugged first plate member having a vertical median portion
and two integral grid-like frame members extending in
opposite lateral directions from the vertical median
portions; pasting the grid-like members with a positive
paste material; folding the first plate member about the
central axis of the first plate median portion to form a
bighted portion whereby the first plate frame members
assume a substantially parallel spaced apart position
extending from the bighted portion to provide a bifurcated
plate configuration with each of said first plate members
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providing a pair of pasted positive surfaces; providing a
lugged second plate member having a vertical median por-
tion and two integral grid-like train members extending in
opposite lateral directions from the vertical median
portion; pasting the grid-like members with a negative
paste material; folding the second plate frame members
about the central axis of the second plate median portion
to form a bighted portion whereby the second plate frame
members assume a substantially parallel spaced apart
position extending from the bighted portion to provide a
bifurcated plate configuraton with each of said second
plate frame members providing a pair of pasted negative
surfaces; fabricating a battery element by interleaving
one of the first plate frame members into the bight of the
second plate member and toward the bighted second plate
median portion spatially separated from the pasted
- negative surfaces of the second plate frame members and
having the plate lugs symmetrically positioned with
respect to said element; providing an N-shaped noncon-
ductive separator; disposing the separator between alladjoining surfaces of said first and second plate members;
inserting a battery element into each cell; connecting the
lugs of the plate members of one polarity in one cell to
the lugs of the plate member of the opposite polarity in
the adjoining cell by forming an intercell connection; and
coupling the unjoined plates in the end-most cells to the
terminal connections outside the battery case.
DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a perspective view of a battery made
according to the present invention;
FIGURE 2 is a perspective exploded view of a battery
element formed according to the present invention;
FIGURE 3 is a view taken along line 3-3 of Figure l;
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A75-34
FIGURE 4 is a view taken along line 4-4 of Figure 3;
FIGURE 5 is a view taken along line 5-5 of Figure l;
FIGURE 6 is a perspective exploded view of an alternate
battery element formed according to the invention; and
FIGURE 7 is a perspective partial section view of a battery
made according to the alternate embodiment shown in Figure 6.
DESCRIPTION OF A PREFERRED EMBODIMENT
Referring to Figure 1, a battery 10 is seen to comprise
an outer case 12 having a cover 13 which may be provided with
a vent cap 14 for venting gases formed within the battery in
a conventional manner. Positive and negative terminals, 15 and
16 respectively, are provided.
Figure 2 shows a battery element 20 which may be provided
within each cell of the battery 10. The element 20 comprises
a positive battery plate 21, a negative battery plate 22 and a
porous nonconductive separator sheet 23. The positive plate 21
comprises a frame 24 and a solid vertically extending lead portion
25. Plate 21 is folded along a vertical center line through
portion 25 and includes a conventional conductive lead grid
within frame 24 to which lead paste is adhered. An upstanding
lug 26 is provided on one half of the plate 21 adjacent to the
fold line. The negative plate 22 may also comprise a similar
pasted conductive lead grid. Plate 22 is folded along a vertical
center line of solid portion 27 and also has an upstanding con-
ductive lug 28 formed on one half adjacent to the fold line.
The folded plates 21 and 22 are interleaved with separator 23
having corresponding folds to define a continuous nonconductive
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separating partition between adjacent plate surfaces. The
conductive lugs 26 and 28 are positioned on diametrically
opposed sides of the element assembly 20.
With reference to Figures 3 and 4, the internal construction
of the battery 10 will now be described. The battery case 12
consists of outer side walls 30 and end walls 31 defining a
hollow interior having partition walls 35 which divide the
interior of the case 12 into individual battery cell compart-
ments 36a, 36b and 36c. A battery element 20 is disposed within
each of the cells 36a through 36c and hereafter, the battery
elements and their associated components will be designated
with a subscript "a", "b" or "c" depending upon whether they
are in cells 36a, 36b or 36c respectively. As is also seen in
Figure 3, spaced ribs 38 are provided on the interior surfaces
of the side walls 30 and partitions 35 in order to hold the
elements 20 in spaced relationship with the side walls 30 and
partitions 35. The first cell 36a has an element 20a in which
the lug 26a of the positive plate 21a is sealingly coupled to
the positive terminal 15 on the outside of the battery case 12
by any suitable welding connection through an aperture 40 pro-
vided within one of the side walls 30. The lug 28a of the
negative plate 22a is coupled by a similar weld through its
adjacent partition wall 35 to lug 26b of the positive plate 21b
in the second cell 35b. Similarly, the lug 28b of the negative
plate 22b of the second element is coupled by welding to lug 26c
of the positive plate 21c in the third cell compartment 36c.
Again, this connection is made by a suitable intercell weld
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A75-34
through the adjacent partition wall 35. Finally, lug 28c of the
negative plate 22c in the third cell is coupled to the negative
terminal post 16 on the exterior of the battery case 12 by a
suitable through-the-wall connection. It will thus be appreciated
that the present construction illustrates a 6 volt battery having
three cells 36a through 36c containing elements 20a through 20c
which are comparable to conventional four plate battery con-
structions but which utilize a pair of folded plates instead.
Obviously more or fewer cells could be provided if desired. The
provision of the lugs 26a through 26c and 28a through 28c eliminates
the need for a strap connection between plates of similar polarity
within the cells and the intercell connection is simply made by
joining a single lug within each cell with a corresponding single
lug in the ad~acent cell or with an external terminal 15 or 16.
The folded design thus permits construction of battery elements
20 having three pieces which perform the same as conventional
elements consisting of four plates and three separators thus
reducing assembly time and material costs.
Because the present battery design is adpated for reduced
capacity batteries, the case 12 has reduced external thickness
with corresponding reduced individual cell sizes. Accordingly,
as seen in Figure 5, a single vent plug 14 is provided which
engages an annular boss 45 formed in the cover 13 and defining
an aperture 46 which opens into the interior of the battery case
12. Aperture 46 extends over the three cells 36a, 36b and 36c
to permit filling of the cells with electrolyte or water through
the single aperture and also allow venting of gases from the
cells.
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Figure 6 illustrates an alternative construction of a
battery element 220. The element 220 consists of a positive
plate 221, a negative plate 222 and a separator 223 as shown
in Figure 2, however, the positive plate lug 225 and negative
plate lug 226 are located centrally along a solid folded portion
227 of the plates 221 and 222 respectively. Lug 226 may be
formed by cutting a "U~shaped" slot 228 in the solid portion
227 so that upon folding of the plate 222, lug 226 will extend
beyond the fold line. Lug 225 of plate 221 may be similarly
formed. This design is more efficient electrically as the lugs
225 and 226 are more centrally located relative to the extreme
portions of the plates 221 and 222. This type of construction
would necessitate a through-the-wall or through-the-partition
connection as shown in Figure 7 in which the positive lug 225
is connected to the positive terminal 215 through side ~all
230 of a battery 210 as previously described. In this case,
however, the connection is made below the normal level of the
electrolyte within the battery 210.
While two embodiments o the invention have thus been
de~cribed, it will be apparent to those skilled in the art that
other variations may be possible without the parting from the
inventive concept. Accordingly the scope of the invention is
not to be limited by the foregoing description but is to be taken
801ely by an interpretation of the claims which follow.
