CA1173497A - Lead-acid battery and method of making same - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A lead-acid storage battery and method for making same characterized by significantly improved performance characteristics, especially for starting, lighting and ignition applications. Compared to commercially available batteries for such applications, batteries according to the present invention provide substantially improved peak power and cranking power per unit weight and volume, typically achieving improvements on the order of about 25 to 65 percent.
Multiple intercell connections and uniquely configured electrode plates are combined with other modified physical parameters in a novel manner to obtain such improvements, employing, if desired, pre-molded containers of standardized external dimensions.

Description

~ 1~3~197 LE~ACID B~TE~ AND MEE~D OF M~KING ~E

The present invention relates to storage batteries, and, more particularly, to lead-acid storage batteries characterized by a high cranking power to weight and volume ratio.
The last several years have seen a number of developments in the lead-acid battery field for starting, lighting and ignition (hereinafter "SLI") applications, perhaps the most significant of which is the maintenance-free battery. Ideally, this type of battery allows use over its service life without the need for any maintenance, such as adding water or the like. The popularity of the maintenance-free battery for SLI applications is widespread at the present time.
However, the battery industry is continually being faced with seemingly ever-increasing demands. There is thus considerable pressure on automobile manufacturers ~.

~ 173~9~

to provide improved performance, e.g. - better gas mileage; and this translates to ef~orts to reduce the overall weight of the automobile as much as possible.
Lighterweight batteries are like~wise being required so as to contribute to weight reductions. Similarly, there is a tendency for requiring a smaller-sized battery, simply due to the amount of space available under the auto bile hood.
At the same time, the number of smaller-sized automobiles with smaller engines currently in service has risen dramatically. While the batteries used for such smaller automobiles can be smaller, the designs required need to be more efficient. Thus, for example, reducing a 350 cubic inch engine to one one half that size does not allow reducing the battery performance requirements to the same extent. The starting or cranking power, as one example, which is required for such a smaller engine, is thus more than one-half of the requirement for the 350 cubic inch engine.
Moreover, four cylinder engines require substantially higher cranking speed to attain engine starting.
Indeed, some four cylinder engines require up to one and one-half to three times the cranking speeds of V-~
engines.
The increase in popularity of diesel-powered automobiles has also contributed to the demand for more efficient batteries. Engines of this type ~hus require more starting power than a comparably sized gasoline-powered engine. As a result, it is not unusual to see a diesel-powered automobile employ two batteries in parallel or utilize an extremely large battery, almost approaching a truck battery size.

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These and other considerations dictate that battery manufacturers provide a battery with substantially improved performance characteristics.
This need has engendered considerable attention.
Substantial effort has thus been directed to enhancing performance of present battery designs by attempts to improve individual components. One example of this are various efforts to provide improved performance by modifying the grid design. U.S. Patents 4,118,553, 4,221,852 and 4,221,854 are specific examples. While perhaps providing some improvement, batteries incorporating such grid designs fall far short of satisfying the ever~increasing requirements being faced by battery manufacturers.
Another attempt to reduce the weight of a battery comprises the use of a plurality of frames, each divided into a number of side-by-side positive and negative active paste support areas. These frames are assembled and secured together in a stack configuration so that the perimeter portions of the frames serve as the top, bottom and two opposite sides of the battery;
and the divisions in the frames serve as cell partitions. Each frame is pasted with active material to provide plates, with adjacent plates in each frame being of opposite polarity, and adjacent plates in adjoining frames also being of opposite polarity. This type of battery construction is exemplified in U.S.
Patent 4,022,951 to McDowall.
Such a battery construction is said to reduce the battery weight and size considerably as well as to eliminate the formation of intercell connections during assembly, with the avoidance of sealing problems, as well as the possible elimination of the requirement for a separate battery case.

3 ~ 7 However, this type ~f battery construction is not amenable to conventional battery assembly techniques.
Utilization would thus require new and different assembly equipment~ creating both a considerable capital investment as well as ~he necessity of gaining knowledge as to what is required from the quality control standpoint. Moreover, it would be difficult, if not impossible, to make the combination positive and negative grids from different alloy materials. As is known, the use of hybrid grids for maintenance-free batteries is often desirable, or even necessary, in some applications. Still further, joined positive and negative grid type of construction would make it qui~e difficult to automate the pasting of active material precursors onto the grids while using separate paste formulations for the positive and negative plates, as is generally practiced. It would also seem difficult to maintain satisfactory electrolyte-tight sealing throughout the service life because of the considerable area of the frames which must be heat-sealed together and the number and type of cell-to-cell connections which are necessary. Thus, in this type of construction, the area which must be heat-sealed could well be about 25 to 50 times that required in the ~5 cover-to-container seal in a conventional battery design. No battery manufacturer has yet been able to demonstrate the reliability that would be required to carry out a heat-sealing operation of this magnitude on a commercial scale.
The McDowall type of combination positive-negative plate construction is representative of the approach wherein cell-to-cell connection is obtained by the combination plate support member in one cell extending 1 1 ~ 3 ~

through the partition and serving as the support member of the plate of opposite polarity in an adjoining cell.
All of such approaches would require relatively complex assembly techniques when considering commercial production.
Still further, prior patents and literature in the battery field are replete with a multitude of configurations and theories for providing improved battery performance by reducing the internal resistance. Yett despite all this substantial prior effort, there still remains the need for a relatively lightweight, small volume battery which can be reliably made on a commercial production basis while providing the ever-increasing performance characteristics being demanded. Stated another way, there still exists a need for a battery which can reliably be made on a high volume, production basis which is characterized by a high cranking power to weight and volume ratio , e.g. -starting power for an automobile, while maintaining the other characteristics required to provide an SLI
battery with a satisfactory useful service life.
A principal object of the present invention is thus to provide a storage battery possessing superior power per unit weight and volume characteristics.
A further object lies in the!provision of a battery amenable to high volume, commercial scale production.
Yet another object of this invention provides a battery which utilizes many of the conventionally used battery assembly techniques. A related and more specific object provides a battery which can utilize battery containers of conventional design and standardized external dimensions. A further and 3 '1 ~ ~

related object provides a lead-acid battery capable of using conventional pasting techniques and separator materials.
Another object of the present invention is to provide a storage battery having a reliable electrolyte-tight sealing structure.
Yet another object of this invention is to provide a battery in which the elements of a cell can be inserted into the battery container as a unit.
Yet another object provides a storage battery which can utilize a hybrid grid alloy construction which allows selecting the grid alloy to achieve optimum positive and negative plate performance.
Other objects and advantages will be apparent from the accompanying drawings, in which:
FIGURE 1 is a perspective view of the battery of the present invention with one end wall being partially cut away to show the connection in the end cell to one terminal and the intercell connections;
FIG ~ 2 is a side elevation of the battery of the present invention and partially cut away to further illustrate the intercell connections;
FIG. 3 is a top plan view of the battery of this invention and partially cut away to show the positioning of the separator, element straps and intercell connections;
FIGr 4 is a cross-sectional view taken generally along line 4-4 of FIG. 3 to illustrate further constructional features;
FIG. 5 is a schematic view of a grid suitable for us~ in making the plates; and FIG. 6 is a schematic view of a grid suitable for making an alternative embodiment.

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While the invention will be described in connection with preferred embodiments, it will be understood that we do not intend to limit the invention to these preferred embodiments. On the contrary, we 5 intend to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the present invention as defined in the appended claims. Thus, while the present invention will be described in conjunction wi~h a SLI automotive battery, it should be appreciated that the invention is equally applicable to any other lead-acid battery application. Indeed, the present invention can be adapted to use with an absorbed electrolyte type of battery, as opposed to the flooded-electrolyte battery illustrated herein. Use of the present invention will be particularly advantageous in applications which require relatively high peak power per unit weight or volume.
In general, the present invention is predicated on the discovery that, by a unique combination of physical parameters, as will be discussed hereinafter, a lead-acid battery can be provided which is characterized by exceptionally high power characteristics per unit weight or volume. Such characteristics are highly advantageous in applications such as automobile starting.
This improvement in performance can be quantitatively set forth in terms of peak power per unit weight of the battery, or per unit volume, of the battery. Peak power is defined in the Society of Automotive Engineers (SAE) publication No. 660029, January 10-14, 196~, titled "Battery Ratings" by Kruger and Barrick. This parameter provides a means for .~. 173L1~

determining the maximum cranking power that a battery will provide for startin~ an automobile. The perform-ance of batteries in accordance with the present invention are characterized in an optimized configura-tion by a peak power, measured at 0F., of at leastabout 200 watts~pound of the gross weight of the battery and at least about 15 watts/cubic inch based upon the total volume ~i.e.- nominal external volume discounting terminals) of the battery, preferably at least about 225 to 235 watts/pound or more and about 17 to 20 watts/cubic inch. Based upon the effective volume of the battery (i.e.- the internal volume minus the head space above the electrolyte level), batteries in accordance with the present invention are capable of providing peak power of at least about 30 watts per cubic inch or so.
The lead-acid batteries of the present invention are also characterized by extremely low resistance-weight equivalents, viz.- a value representing the product of the average internal resistance of a cell of the battery multiplied by the total weight of the cell.
This value is determined by dividing the total internal resistance of the battery by the number of cells and multiplying this resulting number by the total weight ~5 of the battery divided by the number of cells. Measured at 0F., batteries in accordance with the present invention in an optimized configuration provide resistance-weight equivalents of about 4.6 milliohm-pounds or less, preferably less than about 4.1 and, more preferably less than about 3.9.
By an "optimized configuration'i in the discussion herein, it is meant that the cell element occupies substan ially the entire internal cell ~olume in the '~ ~7'3~197 battery container, as will be more ~ully described hereinafter. However, the present invention can utilize, if desired, an over sized container relative to the size of the cell element required for the particular performance characteristics. This may be desirable, for example, in the battery replacement market where particular applications require standardized battery container sizes.
In these instances, the advantages of the present invention are derived principally from cost savings, as, for example, resulting from more efficient lead utilization. Such advantages can be seen by reference to the resistance lead weight equivalent. This parameter is a measure of the effective utilization of the lead in the battery and is most usefully characterized on a per cell basis to provide an average value. This is determined by dividing the total weight of lead in the battery (viz. - the total weight of the lead component, in free and in combined form, in all of the components of the battery; stated another way, the total weight of metallic lead and lead compounds present in the battery as determined on a dry, unformed basis) by the number of cells and then multiplying that figure by the value determined by dividing the total internal resistance of the battery by the number of cells. Measured at 0F., the batteries of the present invention are characterized by resistance-lead weight equivalents of no more than about 3.3 milliohm-pounds, preferably no more than about 3~0, more preferably no more than about 2.85, and even more preferably less than about 2.7 or 2.5. The corresponding peak power level based upon the weight of the lead in the battery 3~

is at l~ast about 280 watts per pound lead, more preferably at least about 340 watts per pound lead.
The batteries of the present invention may also be characterized in relation to the O~F. Cold Performance test which is standard for the United States automotive battery industry. In this test, a battery is rated at the number of amps (termed "cold cranking amps") which can be drawn from the battery while providing a voltage at 30 seconds of no less than 7.2 volts. This Cold Performance test is considered to provide a measure of the starting power of the battery. Batteries of the present invention in an optimized configuration are characterized by cold cranking currents of at least about 1~ amps/pound based upon the gross weight of the battery, preferably at least about 17.5 amps/pound, and more preferably, at least about 20.0 amps per pound.
Considered by volume, batteries in accordance with this invention typically provide at least about 1.5 cold cranking amps per cubic inch based upon the total volume, more preferably at least about 1.7 amps per cubic inch. Based upon the effective volume, batteries of the present invention provide at least about 202 cold cranking amps per cubic inch, more preferably at least about 2.5 cold cranking amps per cubic inch.
Based upon the total weigh~ of lead in the battery, batteries of the present invention provide at least about 30 to 31 cold cranking amps/pound of lead weight.
To provide a specific example of what these parameters mean, a commercially available, Group 24 maintenance-free, 12-volt battery, nominally rated at 550 cold cranking amps, weighs about 42 pounds and employs a container having a total volume of about 577 3'~

cubic inches. In marked contrast, a battery made according to the present invention and also nominally rated at 550 cold cranking amps, will weigh about 30 pounds or so and can be placed in a container having a total volume of only about 345 cubic inches. On the other hand, a battery utilizing the present invention with a container volume of the same external dimensions as the commercial battery described above will provide a nominal cold cranking rating of about 850 to 900 amps or so, the weight of such battery being about 3 to 4 pounds heavier than the above Group 2~ commercial battery.
This marked difference in performance may also be seen by comparing the peak power characteristics. The Group 24 commercially available battery provides a peak power of about 5120 watts at 0DF. which translates to about 121 watts per pound of the battery and about 8.9 watts per cubic inch based upon the total volume. The battery of the present invention, by way of contrast, provides a peak power o~ about 7000 watts, corre-sponding to about 230 watts per pound and about 20.3 watts per cubic inch, based upon the total volume.
These exceptional battery performance characteristics permit the battery of the present invention to provide starting or cold cranking power which is equivalent to some truck batteries that weigh substantially more. In some cases, batteries according to the present invention, weighing 35 pounds or so, have provided more cranking power than some truck batteries weighing over 100 pounds.
Turning now to a more detailed description of the present invention, there is shown in FIGS. 1-5 a preferred embodi~ent of a 12-volt, 6-cell battery of ~. ~73~97 the present invention. As seen in FIG. 1, the battery 10 comprises, in general, a premolded container 12, a cover 14 attached to the container by any suitable means, a positive terminal post 16 and a negative terminal post 18. While illustrated as top terminals, side terminals or other terminal configurations could likewise be employed.
The container 12, as best seen in FIGS. 2-4, is divided into a plurality of cells by integrally formed partition walls 20 which lie in generally equally spaced planes essentially parallel to the end walls 22 of the container 12.
Each cell has a plurality of independent, alternately disposed, positive electrode plates 24 and negative electrode plates 26. As illustrated, in accordance with one preferred aspect of the present invention, the plates 24 and 26 are disposed generally perpendicularly to the cell partitions 20.
When positioned in this fashion in conventionally sized automotive battery containers, i.e., - batteries having standardized external dimensions for example, as set by S~E for automotive batteries in the United States and by other organizations in other countries, such as Deutsche Industrielle Norme (DIN) of the Federal Republic of Germany, the height to width ratio of the plates will be at least about 2:1, often at least 3:1 or more, perhaps up to about 4:1 or 5:1.
In accordance with the present invention, the total area of the plates is about one-fourth to one-sixth that of the area of conventionally sized SLIplates. This corresponds to a plate area for an individual plate of about 5 to about lO square inches.
It has been found that plates within this area range 13~19~

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are satisfactory to provide the desired power charac-teristics for batteries in accordance with the present invention. It is believed that such relatively small plates provide a more e~fective utilization of the conductive portions of the plates, as will be more fully discussed hereinafter~
FIG. 5 sets forth an illustrative example of a useful independent supporting and electrically conducting member, viz.- grid, for the electrode plates 2~ and 26. The grid, shown generally at 28, includes an outer frama bar 30, cross wires 32 and 34 which intersect to ~orm generally equivalent windows or active material pellet areas 36, an electrical connection means such as a plate lug 38 and a foot 40.
The grid design shown is only exemplary, and many other configurations could be used as the particular design is not critical. All that is required is that the grid adequately function to support the active material which must be included to make up the electrode plate and to relatively efficiently carry the current generated to the collection point, viz. - the plate lug 38. As may be appreciated, however, the use of more efficient grid designs could contribute to further reductions in internal resistance and, consequently, improved electrical performance.
In accordance with one aspect of this invention, the grids utilized are relatively thin. It has thus been found suitable to utilize grids having a nominal thickness in the range of about 0.030 to about 0.065 inch, more preferably about 0.035 to about 0.045 inch.
The nominal thickness will typically be determined by the thickness of the outer frame bar 30, as the cross wires 32 and 34 are generally somewhat thinner than the 1 ~73~l~7 frame ~ar 30. ~rids thicker than those described herein may be employed but may detract somewhat from the performance obtained. On the other hand, grids thinner than about 0.030 inch can conceptually be used.
However, the manufacture of extremely thin grids is quite difficult with existing technology. Moreover, the service life requirements needed should be taken into consideration as the corrosion which will occur in service may dictate the minimum thickness which is desirable. It is generally desired to maintain the weight of the grid at about 1.5 to about 2.0 grams per square inch of grid area. The weight per unit area employed will typically increase as the area of an individual plate is increased.
The alloy used for the grids is not particularly critical~ Many suitable alloys for lead-acid battery grids are known. However, in view of the widespread usage of maintenance-free batteries, it is preferred to utilize alloys capable of achieving maintenance--free performance. Many alloys of this type are likewise known and may suitably be employed. Where maintenance-free applications require optimum cycle life, it is preferred to use a low antimony, maintenance-free alloy for the positive grids and an antimony-free alloy for !' 25 the negative grids.
The grids may be made by any suitable tecnniques.
Techniques using casting or expanded metal are known and may be utilized.
To provide the electrode plates, appropriate positive and negative active material or its precursor must be applied to the grid which serves as a support for such material. This can be accomplished by using a conventional active material (or a precursor) formula-tion and then applying such formulation to the grid, as 1~3~97 by pasting or otherwise applying such formulation onto the gridr as is well known.
The use of independent positive and negative electrode plates allows maximum flexibility in design.
Different alloys and different active material (or their precursors) formulations may thus be employed;
tailored to give the optimum performance for the particular intended batte~y application.
From the functional standpoint, only that amount of paste weight per unit area is utilized which is necessary to satisfy the desired cold cranking perform-ance. Excessive amounts will tend to detract from power per unit weight or volume efficiencies; however, other performance requirements (e,g.- reserve capacity) may dictate the use of greater amounts of paste. At conventionally used densities, it has been found suitable to employ dry pasted weights on the order of about 2.5 grams per square inch of plate area when a grid thickness of about 0.040 to 0.045 inch is used.
As is conventional, separator means are used to separate the positive and negative electrode plates.
Any separator means useful for lead-acid batteries may be employed. It has been found suitable to space the electrode plates in the battery of the present invention with the same spacing as used in conventional lead-acid batteries, viz. - typically about 37 mils (0.037 inch) apart. The separator means used should desirably include ribs or other means to allow gas generated at the electrode plates to escape upwardly out of the container 12.
In accordance with yet another and pre~erred aspect of this invention, the separator means in each cell comprises a continuous strip of separator material 73~(3~

which is fol~ed in accordion fashion, with the positive and negative electrode plates being alternately positioned in folds on opposite sides of the separator material. To this end, the separator 42 in each cell illustrated in FIGs. 1-4 is a continuous strip of material folded in accordion fashion~ Materials useful for maintenance-free applications are preferred. For such applications, it has thus been found satisfactory to utilize commercially available silica-polyethylene separator materials. As one specific example, materials of this type in a nominal 10 mil thickness with ribs to provide electrode plate spacings of about 37 mils have been found satisfactory. The ribs should face the positive electrode plates and be configured to provide a path to allow the gas generated to escape upwardly and ultimately out of the container. One method of assembly of the separator and plates into a cell element stack is described in the co-pending Oswald et al application described herein. The particular assembly method used does not form a part of the present invention.
The separator resistance and the spacing between electrode plates will affect the overall internal resistance of the battery. To provide optimum performance, it is accordingly preferred to utilize a separator having a resistance, at 80F., of no more than about 10 milliohm-in.2 (~ 2 milliohm-in.2) or so; and the commercially available silica-polyethylene materials described herein meet this criteria.
Separators with higher resistances can, of course, be utilized, depending upon the electrochemical perform-ance characteristics desired for the particular battery application.

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3 ~-1 9 ~

Similarly, providiny closer plate spacing than 37 mils will decrease the internal resistance due to the electrolyte. Increasing the spacing will have the opposite effect.
The performance characterisl:ics of the batteries of the present invention described herein have been derived using a 37 mil electrode plate spacing with a separator meeting the preferred resistance criteria described. ~s should be apparent:, some or all of the advantages of this invention can be derived by utilizing less than an optimum combination of plate spacing and separator resistance. Thus, many separators with resistances in the range from about 12 to 30 milliohm-in.2 are available and are often employed in lead-acid battery applications. Use of such higher resistance separators will detract somewhat from performance but may be acceptable for some appli-cations. For example, use of a separator with a resistance of about 30 milliohm-in.2 and 37 mil spacing will provide a battery in accordance with this invention having a resistance-weight equivalent of about 4.9 milliohm-pounds.
Suitable venting means for the battery may be provided, as is conventional; and any of the several conventional vent plugs may be used. As best seen in FIGS. 1 and 2, the illustrative embodiment provides a single vent for each cell, the vent plug, shown generally at 44, being of the type often used for commercially available maintenance-free automotive batteries. Internal gasses escape through channels formed on the underside of cover inserts 46 which are press fitted into the cover 14.

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Means should also be provided to minimize the possibility of internal shorts occuring due to sediment collecting in the bottom of the container. More particularly, as is known, battery use results in shedding of active material and the like which then collects in the bottom of the container. This sediment buildup can create an e:Lectrical path which bridges adjacent positive and negative electrode plates, thereby creating an internal short.
Such means can be provided by molding the bottom of the container 12 with upstanding ribs or shoulders 48 adjacent and generally parallel to the partition walls of the cells, as is best seen in FIG. 2. These ribs or shoulders 48 cooperate with the feet 40 of the electrode plates to position the plates sufficiently above the cell bottom so that, in service, any conductive bridges that would otherwise result in internal shorts being created should be avoided. The particular distance that the lower part or bottom of the electrode plates are maintained above the bottom of the cell can be similar to that used in conventional battery construction.
More preferbly, and as is employed in some commercial maintenance-free batteries, the bottom of the cell can be filled with an electrolyte-resistant adhesive, such as an epoxy resin, sealing compound, or hot melt, sometimes used in the battery industry, so that the electrode plates and/or separators are potted in place. Securing the bottom of the plates, or the foot 40 of the plates in the illustrative embodimentr will provide improved vibration resistance.
Still further, and as will be described in more detail hereinafter, the electrode plates and separators ~ 3L73~1~7 can be suspended in the cell by the intercell connec-tion means used so that there i5 adequate spacing from the cell bottom. In this instance, it will generally be desirable to size the separator so that its lower or bottom edge slightly overhàngs the bottom of the electrode plates, as is shown in FIG. 2.
For optimum performance characteristics, as has been previously noted, it will generally be desirable to size the element stack employed so that the cell element stack, formed by the electrode plates and separator, will snugly fit in the container cells. In other words, the cell element is sized relative to the cell so that it can just be conveniently inserted. The tolerance between the cell element and the cell side walls may thus suitably be about 1/16 or 1/32 of an inch to provide a snug fit. This sizing allows optimum usage of the available internal battery space, and, in this respect, an optimized configuration~
Alternatively, and as is illustrated in FIG. 3, ribs shown at 50 may be integrally molded into the sidewalls 52 of the plastic container 12 to hold the cell element in position when an oversized container is used. Indeed, if desired, an oversized container can be employed without the need for ribs or other positioning means. However, in such instances, electrolyte, in excess of that needed for satisfactory operation, will be present so that the use of a suitable lightweight foam or other volume-reducin~
means may be desirably employed to displace such excess electrolyte, thereby providing a lighterweight construction.
In accordance with this invention, conductive element straps electrically connect in parallel plates 20 ~-~73~lg'~

of like polarity in each cell element. The electrical connections may be carried out by any of the conventionally used techniqueS, typically providing a fused connection.
Thus, in one end cell, as is illustrated, a first conductive strap is electrically connected to the electrical connection means or lugs of each of the independent positive electrode plates and to the positive terminal. As shown, in FI~s. 1 and 2, a strap 54 i~ accordingly connected to the lugs 38 of the positive electrode plates 24 and, in turn, to the positive terminal 16.
In the other end cell, a second conductive strap is electrically connected to the electrical connection means or lugs of each of the independent negative electrode plates and to the negative terminal. Strap 56, as seen in FIG. A, is thus connected to the lugs 38 of the negative electrode plates 26 and, in turn, to negative terminal 18.
Similarly, a third conductive strap61 connects in parallel to each of the ~ e~ent positive electrode plates in each cell other than the positive terminal cell. Likewise, a fourth conductive strap in each cell other than the negative terminal cell electrically connects in parallel each of the negative electrode plates~ A fourth conductive strap 60 in each cell other ~han the negative terminal cell is thus electrically connected to the lugs 38 of each of the negative electrode plates 26.

1 1'~349'`~

Pursuant to yet another aspect of the present invention, at least two intercell connectors per cell electrically connect in series adjoining cells. In the preferred embodiment, the intercell connectors use a through-the-partition configuration. The number of intercell connectors utilized wi:Ll in large part be determined by the number of plates per cell. Many applications make the use of at :Least three intercell connectors preferable. In some applications where an extremely large number of plates per cell are used, e.g. - about 60 or more per cellv it may be desirable to utilize four intercell connectors to connect adjoinin~ cells. To this end, and as illustrated in FIGs. 1-4, the third conductive strap 61 has three upstanding intercell connector buttons 62 which a~ut apertures 64 in the cell partitions 20. The fourth conductive strap 60 in the adjoining cell has three upstanding intercell connector buttons 66 which likewise abut apertures 64. In the assembled condition illustrated, buttons 62 and 66 are shown fused together, resulting in electrolyte-tight, intercell connections.
The intercell connections are suficiently strong so that, if desired, the positive and negative electrode plates can be suspended from the conductive straps without additional support at the bottom of the plates being required. This may be particularly useful where the grids forming the supporting member for the electrode plates are made by expanded metal techniques.
It is believed that these multiple intercell connec-tions provide a battery which is less prone to damage caused by vibration, as could result from use in service or the like.

, ~ ~ 3 '~ ~ ~

The respective conductive straps, as well as the intercell connector buttons associated with the ~hird and fourth conductive straps, can be connected to the respective positive and negative electrode plates either before or after insertion into the battery container. It is preferred to utili~e an element stack as described in the related application identified herein, inasmuch as the m~ltiple components required can be then easily handled as a unit. This element stack can be subjected to a cast-on-strap operation by which the straps and buttons can be cast on the lugs in a single operation to provide a cell element. Conven-tional cast-on-strap techniques are known and may suitably be utilized. After the cell elements are in position in the container, the intercell connections can be made by electrical welding or gas-burning techniques to form the fused intercell connections shown in the illustrative embodiment.
The formation of the active material precursor paste typically used can be carried out by known techniques. Thus, formation may be carried out in a one step operation using a sulfuric acid electrolyte with a relatively high specific gravity, e.g.- 1.200 or so, or in a two step procedure involving charging in a relatively low specific gravity electrolyte, e.g.-1.060 or so, followed by dumping and then soaking with a higher specific gravity electrolyte. In either event, the full charge specific gravity of the electrolyte for SLI service applications will be in the range of about 1.265 or so.
The level of electrolyte in the container can be varied as desired but will generally be up to the top ~ ~73/197 of the electrode plates. This is all that is required to provide the electrical performance characteristics of the batteries of this invention. However, in flooded-type batteries, it is useful to provide a level above the electrode plates so that a reservoir, in effect, of excess electrolyte is created, both for maintenance-free applications as well as for improved lower rate performance (e.g.- reserve capacity).
As can be seen, the illustrative embodiment provides efficient intercell connection. The conduc-tive straps electrically connecting plates of like polarity within the inter-connected cells are thus adjacent, generally parallel to, and extending substantially the length of the cell partition in an optimized configuration. This efficient intercell connection contributes to the vastly superior cranking power performance characteristics exhibited by the batteries of this invention.
To provide the lead-acid batteries of the present

2~ invention, the several physical parameters discussed herein are selected relative to each other to provide the exceptional power per unit weight or volume characteristic of such batteries. It is the inter-relationship of such parameters which achieves such characteristics.
The relatively small area of an individual plate in comparisGn to conventional SLI lead-acid batteries contributes substantially. This provides an extremely efficient conductive member. At a given total plate area, the use of more plates, each of drastically reduced area, dramatically reduces the internal resistance of the battery.

~ ~3~
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This high efficiency allows the weight or mass of the grid portions of the plates per unit area to be substantially reduced. The reduction in mass affects the balance between the resistance due to the electrolyte and the electronic resistance due to the plate. The mass of the grid selected should be such as to provide a relatively optimum balance, the balance being quite different from the balance used in conven- -tionally designed batteries. Stated another way, the mass will desirably be selected such that either increasing or decreasing the grid weight per unit area will not increase to any significant extent the power characteristics per unit weight. This reduction in mass may correspond, as an example, to about 91 percent per unit area of that used in conventional batteries.
Further, using typical automotive paste densities, the mass per unit area of the active material paste employed is reduced significantly. Thus, the active material paste mass per unit area is reduced to only ~0 that amount necessary to satisfy the desired cranking requirements. As an example, the total paste mass per - unit area may be about 83 percent of that convention-ally used.
Accordingly, the total plate mass per unit area of batteries in accordance with the present invention is about 86 percent of that of conventional batteries.
As is known, the cold cranking performance of lead-acid batteries is, in general, dependent upon the effective total plate area. Thus, to actually deliver a particular cold crank rating, a minimum effective total plate area is needed. If that minimum is not provided, the average current density (based upon the effective plate area) which results will change the ~ 1~3'1~7 slope of the voltage-time curve to the extent tha~ the battery may well fail the cold performance test. As an example, conventional batteries are generally designed such that the average current Aensity does not exceed a value in the range of about 1.8 amps per in.2 or so.
In contrast, the batteries of the present invention are characterized by relatively high terminal voltages (e.g.- 5 second voltage). This allows a reduction in the effective plate area neede~ to deliver a particular cold crank rating since the sharper slope of the voltage-time curve that will result should still provide the required 7.2 volts after 30 seconds. Thus, as an example, a battery pursuant to the present inven-tion may be designed such that the average current density is in the range of about l.9 to 2.2 amps per in.2. This allows the effective plate area in the batteries of this invention to correspond to about 88 percent of that needed in conventional batteries.
Still further, a plate surface which does not face the surface of a plate of the opposite polarity does not contribute to any significant extent to the effective plate area, as there is an extremely high resistance path to any plate surface of opposite polarity. On each side of a cell, the outer surface of the two outside plates is thus substantially wasted.
As one example, the percentage of wasted plate area in a conYentional battery may be on the order of 9 to 10 percent. In batteries pursuant to the invention, the wasted plate area, as an example, can be reduced to about 1.8 to 2 percent or so. Due to this end plate effect, the total plate area of the batteries of this invention need only be about 92.5 percent of that in conventional batteries.

:~ 1'73~.97 While the magnitude o any one of these three weight and area reduction effects is significant, the cumulative effect is dramatic. The total lead weight of the plates required to provide a battery pursuant to the present invention with power characteristics (e.g.-cold cranking performance) equivalent to that of conventional batteries is only about 70 percent or so (viz.- .86 x .88 x .925 x 100) of that required in conventional batteries.
It should also be appreciated that the efficient intercell connection previously clescribed likewise contributes significantly to the improved performance of the batteries of this invention. Thus, the total top lead (viz.- weight of straps and terminals) may be reduced to abo~t 75 percent of that used in conven-tional batteries due to the efficient current paths of the intercell connections of batteries designed in accordance with this invention. It has also been found that the internal resistance of the intercell connec-tions of such batteries is about 75 percent of that ofconventional batteries. The net effect is that the cell-to-cell connections of the batteries of this invention may be on the order of about twice as efficient on a unit lead basis as that of conventional 25 batteries. !' Still further, since the lead weight of the plates per unit area has been reduced, the amount of electro-lyte may likewise be correspondingly reduced. This also contributes to the improved power characteristics per unit weight of the batteries of this invention.

' .~L 1 71 3 ~ 9 ~

This unique interrelationship of physical parameters together with the efficient cell-to-cell electrical connections provide a battery characterized by, at a nominal rated cold cranking, an extremely high initial terminal voltage ~e.g.- 5 second voltage), viz.- on the order of, typically, 8.3 to 8.6 volts or so in relation to that of conventional batteries which vary from perhaps about 7.4 to 7.9 volts or so. What this means from a production standpoint is that internal resistance as a cause of failure upon cold cranking is virtually eliminated. This is in marked contrast to conventional batteries where the margin of error (i.e.- the increment of the initial terminal voltage above 7.2 volts) may be so small that, through manufacturing variation or the like, the battery will not deliver its rated cold crank. Moreover, even when compared with conventional batteries of identical cold crank rating, batteries pursuant to the present invention possess significantly higher power which translates to substantially greater starter and, thus, engine cranking speed for starting an automobile.
The foregoing subsumes the desire to optimize the power characteristics per unit weiyht or volume.
Particular applications may make it desirable to provide greater low rate capacities, e.g.- reserve capacity, which may detract somewhat from such power characteristics. For example, to provide more reserve capacity, it may be useful to increase the mass of active paste over that discussed above. This will diminish somewhat the power characteristics; yet, such characteristics will still remain substantially superior to that of conventional batteries.

3 '`I ~

Conventional battery designs can be modified to gain some of the advantages of the power characteris-tics of this invention. To this end, by providing electrode plates of conventional size with at least two connector lugs and with at least two through-the-partition connections, and preferably at least three, performance is significantly enhanced. Thus, in a conventional 13-electrode plate cell element, a total of at least 39 lugs per cell will be utilized in the preferred embodiment. A suitable grid 68 for accomplishing this alternative embodiment is shown in FIG. 6. The grid 68 includes an outer frame bar 70, cross wires 72 and 74, and multiple lugs 76, 78 and 80.
The lugs for the positive and negative grids should, of course, be offset so that the necessary conductive straps and intercell connections can be made. In any event, the particular electrode plate configuration employed should provide at least one lug per about every 14 square inches of electrode plate area, more preferably, at least one lug for every 12 square inches.
In addition, modifying the physical parameters of a battery utilizing the multiple lug plates in accordance with the principles discussed herein should further enhance the power characteristics when compared to those of a conventional battery. The resulting battery should thus possess power characteristics on the order of those described for the preferred embodi-ment of this invention. It is not, however, believed that this alternative embodiment can equal the more preferred power characteristics of the preferred embodiment.

~ 1~3'~9~

Also, this alternative design may make the connection to the terminals quite cumbersome. It may therefore be desirable to modify the con~truction of the plates of one polarity in its terminal cell by utilizing a single lug per plate, and, thus, a single strap, positioned adjacent the terminal. This will detract from the desired power characteristics but may be preferable to the manufacturing problems likely associated with a construction requiring multiple, spaced straps to be connected to the terminal.
The following Examples are illustrative of, but not in limitation of, the present invention.

A series of batteries in accordance with the present invention were constructed using the configuration shown in the illustrative embodiment.
Conventional Group 22 containers were used, modified to provide ribs or shoulders 48 as generally shown in FIG. 2.
The positive grids were cast from an antimony-lead alloy having a nominal composition of, ~y weight, about 1.5~ antimony together with other alloying ingredients.
The nominal thickness of the grid was about 45 mils. A
standard positive active material paste formulation was used, applied at a rate to yield about 2.5 grams of dry active material precursor per square inch. Each grid had a height of 4.5 inches, a width of 1.17 inches and a weight of about 10 grams.
The negative grids were cast from an alloy having a nominal composition of, by weight, about 0.12 calcium, 0.3% tin, and the remainder lead. The nominal thickness was about 45 mils. A standard negative active material paste formulation was used, ~ 173~

applied at a rate to yield of about 2.5 grams of dry active material precursor per square inch~ The height, width and weight of the negative grids were the same as the positive grids.
The separator used was a commercially available "Daramic"~silica-polyethylene material with a nominal 10 mil thickness, a resistance of about 8 to 12 milliohm-in.2, and with ribs to provide a spacing of about 37 mils between the positive and negative plates.
A continuous strip of separator material was used for each cell, folded in an accordion fashion as shown in FIG. 1.
Twenty-eight positive and twenty-eight negative electrode plates were used per cell. Sulfuric acid electrolyte of 1.265 full charge spe~ific gravity was included.
These batteries were subjected to conventional Reserve Capacity and 0F. Cold Performance tests. The resulting 0F. performance characteristics are set forth in Table 1, the values being those for a 90%
compliance level and compared to those same values for commercially available, maintenance-free batteries:
TABLE l Ex. 1 Commercial Commercial Battery Group 2~ Group 22 Reserve Capacity (Minutes) 70 110 76 Peak Power* 7156 5166 4278 Peak Power Watts/in.3* 15.4 8.9 9.2 Peak Power Watts/lb.* 235 121 138 30 Cold Cranking Amps (nominal rating) 560 550 435 Cold Crank-Amps/lb. 18.4 12.9 14.0 Cold Crank-Amps/in.3 1.2 0.95 0.94 ~ t~3~9'7 ResistanCe-weight e~uiva-lent-milliohm-lbs~ 3.9 7O6 6.7 Resistance-lead weight equivalent-milliohm-lbs. 2.3 4.7 4.0 *calculated by using measured internal resistance The batteries of the present invention thus provide cold crank performance which exceeds, based upon the weight and size of the container volume or cube, that of the Commercial Group 24 batteries. Gross weight reduction of about 12.1 pounds and a volume reduction of about 113 cubic inches is provided. More-over, the peak power output is substantially improved;
and this would indicate that the starting power of the batteries of this invention should be substantially superior even though the nominal cold cranking ratings are virtually the same.
While there are no weight or volume differences when compared with the conventional Group 22 batteries, the nominal cold cranking rating of the present invention is markedly increased (560 vs. 435 amp).
Comparison of the Pea~ Power (7156 watts vs. 4288 watts) likewise shows the substantially improved performance.

Batteries similar to that in Example 1 were constructed, except that a total of 72 electrode plates per cell were used, providing a more optimum configuration for the size container employed. The batteries were tested as in Example 1. The total battery weights were each about 35.5 pounds.
Table 2 sets forth the 90% compliance levels for the batteries tested:

l 173~7 Reserve Capacity (Minutes) 92 BCI Cold Crank-Amps 735 Peak Power-Watts* 9171 Peak Power Watts/in.3* 19 8 Peak Power Watts/lb.* 258 Cold Crank-Amps/lb. 20.7 Cold Crank-Amps/in.3 1.58 Resistance-weight equivalent -milliohm-lbs. 3.56 Resistance-Lead weight equivalent-milliohm-lbs. 2.33 *calculated by using measured internal resistance By comparison with the less than optimum design shown in Example 1, the results set forth for the batteries in this Example further demonstrate the substantial improvements which can be obtained when an optimized configuration is used.
The improved performance capable of being achieved by use of the present invention can be further illustrated by comparing, for various SAE battery group sizes, batteries made in accordance with this invention to batteries considered by the assignee of this invention as being their present top-of-the-line, !~
conventional design, maintenance-free batteries.
Table 3 below sets forth this comparison, "CCA"
representing the nominal cold cranking rating in amps "WT." being the gross weight of the battery and "AMPS/LB." being the quotient obtained by dividing the first two values:

3 ~ (3 ~

~TTERY OF PRESENT IN~E~rIOM
PRESENT CCNSTRUCllON OPTIMIZED OONFIGURATIoN* EQUIVAlENT
SAE WEIGHT
GRD~P CCA WT. ~S/LB. CX~ WT. AMPS/LB. OONFIGURATION**

21 350 29.8 11.75 670 35.2 19.03 475 22 435 32.2 13.51 7~!0 37~6 19.15 515 24 550 41.5 13.2S 850 45.4 18.72 665 27 610 48.0 12.71 980 51.8 18.92 770 41 620 41.7 14.~7 800 42.5 18l~2 670 42 380 29.6 12.~3 600 32.6 18.4 475 54 310 25.1 12.35 ~70 30~6 18.63 400 380 30.2 12.58 640 34.7 18.44 485 56 ~50 35.8 12.57 730 41.2 17.72 575 57 310 26.3 11.78 550 29.2 18.84 420 58 41~ 32.2 12.73 600 33.3 18.02 515 61 310 27.8 11.15 600 32~ 18.4 445 62 380 32.2 11.80 670 37.0 18.11 515 63 450 3B.4 11~72 760 44.0 17.27 615 64 535 44.6 11.99 880 50.0 17.6 715 71 390 31.6 12.34 670 35.2 19.03 505 72 435 32.2 13.5 720 37.6 i9.15 515 73 480 36.2 13.26 750 38.9 19.28 580 74 550 41.3 13.31 850 45.4 18.72 660 77 610 47.8 12076 980 51.8 1~.92 765 *~enotes that the cell element is sized to snugly fit in the container as previously described herein.
**Nominal cold cranking in amps based upDn a configuration having ~he same weight as the p~esent construction hatteries, viz.-the rating was calculated by multiplying the weight of the PRESENT CONSTRUCTION batte~y by 16 a~ps/pound (considered to he easily achievable performanoe using the present invention)~

's 7 3 '~ 3 7 3~

Table 3 shows the significant improvement obtained by using the present invention, whether an optimized configuration is used or a configuration of the same weight is employed. Indeed, significant weight reductions can be achieved by decreasing the number of plates per cell employed, to about 40 or so, while still providing satisfactory cranking performance. It may even be satisfactory for some applications to utilize cells having as few as 30 plates per cell or so, perhaps as few as about 24.
The total number of plates per cell employed may generally be dictated by the reserve and ampere~hour capacities desired. Utilizing more plates will like-wise increase the nominal Battery Council International (BCI) cold cranking rating and peak power value but should not significantly alter the cold crank amps and peak power per unit weight or volume that will be achieved.
Thus, as has been seen, the present invention provides a battery with substantially improved power characteristics to weight or volume ratio in comparison to conventional SLI batteries. Yet, such batteries can be constructed by utilizing, i~ desired, many of the conventional battery assembly techniques. Indeed, the batteries of this invention are accordingly amenable to high volume production on a commercially attractive basis.

Claims (54)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A lead-acid battery comprising a container having a plurality of cells having at least one partition wall, said plurality of cells including positive and negative terminal cells, each cell containing a plurality of alternating positive and negative electrode plates separated by separator means and constituting a cell element stack, each of said plates comprising a grid having active material pasted thereon, the positive electrode plates of the cell element in the positive terminal cell electrically connected to a positive terminal, the negative electrode plates of the cell element in the negative terminal cell electrically connected to a negative terminal, the electrode plates of each cell element electrically connected in series to the electrode plates of opposite polarity in the adjoining cell by at least two intercell connectors; and sulfuric acid electrolyte in contact with the positive and negative electrodes and separators in each cell, the size and total number of grids, the mass per unit area of each grid, the mass of paste per unit area, the manner of electrical connection cell-to-cell and the weight of electrolyte used being coordinated to provide a battery having a peak power of at least about 280 watts and cold cranking amps of at least about 30 amps per pound lead.

2. A battery as set forth in Claim 1, wherein said electrode plates positioned in each cell are perpendicular to said partition.

3. A battery as set forth in Claim 2, wherein an element strap electrically connects in parallel plates of like polarity in each cell, said element strap being generally parallel to said cell partition and having a length substantially equal to said cell partition.

4. A battery as set forth in claim 1, wherein said element stack in each cell occupies substantially the entire available cell space.

5. A battery as set forth in claim 1, wherein said intercell connections are fused connections.

6. A battery as set forth in claim 31 wherein said electrode plate-to-element strap connections are fused connections.

7. A lead-acid battery as set forth in claim 1, wherein there are at least three intercell connections.

8. A lead-acid battery as set forth in claim 7, wherein said intercell connections are fused, through-the-partition connections.

9. A lead-acid battery as set forth in claim 1, wherein said battery provides a peak power of at least about 200 watts and at least about 16 cold cranking amps per pound based upon the weight of the battery.

10. A lead-acid battery as set forth in claim 9, wherein said battery provides peak power of at least about 225 watts per pound based upon the weight of the battery.

11. A lead-acid battery as set forth in claim 9, wherein said battery provides at least about 17.5 cold cranking amps per pound based upon the weight of the battery.

12. A lead-acid battery as set forth in claim 1, wherein said separator means has a resistance at 80°F.
of no more than about 10 milliohm-in.2.

13. A lead-acid battery as set forth in claim 1, wherein said separator means comprises a continuous separator strip folded in accordion fashion.

14. A lead-acid battery as set forth in claim 1, wherein said cells contain an electrolyte-resistant material anchoring said plates to the bottom of the cells.

15. A lead-acid battery as set forth in claim 1, wherein said plates are independent of each other and having an upstanding lug, said plates being generally perpendicular to said cell partition, and an element strap electrically connected in parallel to plates of like polarity in each cell, said element strap being generally parallel, and adjacent, to said cell partition.

16. A lead-acid battery as set forth in claim 15, wherein said plates each have an area of about 5 to about 10 square inches.

17. A lead-acid battery as set forth in claim 1, wherein each cell has at least about 24 plates.

18. A lead-acid battery as set forth in claim 17, wherein each cell has at least about 30 plates.

19. A lead-acid battery as set forth in claim 18, wherein each cell has at least about 40 plates.

20. A lead-acid battery as set forth in claim 1, wherein said container is a pre-molded container having standardized external dimensions.

21. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 24 and said battery has a cold cranking current of at least 665 amperes.

22. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 27 and said battery has a cold cranking current of at least 700 amperes.

23. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 71 and said battery has a cold cranking current of at least 505 amperes.

24. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 21 and said battery has a cold cranking current of at least 475 amperes.

25. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 22 and said battery has a cold cranking current of at least 515 amperes.

26. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 41 and said battery has a cold cranking current of at least 670 amperes.

27. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 42 and said battery has a cold cranking current of at least 475 amperes.

28. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 54 and said battery has a cold cranking current of at least 400 amperes.

29. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 55 and said battery has a cold cranking current of at least 485 amperes.

30. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 56 and said battery has a cold cranking current of at least 575 amperes.

31. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 57 and said battery has a cold cranking current of at least 420 amperes.

32. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 58 and said battery has a cold cranking current of at least 515 amperes.

33. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 61 and said battery has a cold cranking current of at least 445 amperes.

34. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 62 and said battery has a cold cranking current of at least 515 amperes.

35. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 63 and said battery has a cold cranking current of at least 615 amperes.

36. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 64 and said battery has a cold cranking current of at least 715 amperes.

37. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 72 and said battery has a cold cranking current of at least 515 amperes.

38. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 73 and said battery has a cold cranking current of at least 580 amperes.

39. A lead-acid battery as set forth in claim 20, wherein said standardized dimensions conform to Group 74 and said battery has a cold cranking current of at least 660 amperes.

40. A lead-acid battery as set forth in Claim 20, wherein said standardized dimensions conform to Group 77 and said battery has a cold cranking current of at least 765 amperes.

41. A lead-acid battery as set forth in Claim 1, wherein said electrode plates each have a length to width ratio of at least 2:1.

42. A lead-acid battery as set forth in Claim 20, wherein said battery provides a peak power of at least about 200 watts per pound of battery weight.

43. A method of making a lead-acid battery having a plurality of cells, each cell including a plurality of positive and negative grids having active material pasted thereon disposed alternately within the cells with a separator therebetween to form cell elements, cell elements in adjacent cells being electrically interconnected, the cells including a positive and negative terminal cell in which the plates of respective polarity are electrically connected to positive and negative terminals, and electrolyte disposed in each cell, said battery having superior power per unit weight and volume characteristics, which method comprises coordinating the size and total number of grids, the mass per unit area of each grid, the mass of paste per unit area, the manner of electrical connection cell-to-cell and the weight of electrolyte used such that said battery has a peak power of at least about 280 watts and cold cranking amps of at least about 30 amps per pound lead.

44. The method of Claim 43, wherein at least about 30 cold cranking amps per pound lead are obtained when said battery is exposed to a current density in the range of about 1.9 to 2.2 amps per square inch.

45. A lead-acid battery comprising a container having a plurality of cells having at least one partition wall, said plurality of cells including positive and negative terminal cells, each cell containing a plurality of alternating positive and negative electrode plates separated by separator means and constituting a cell element stack, each of said plates comprising a grid having active material pasted thereon, the positive electrode plates of the cell element in the positive terminal cell electrically connected to a positive terminal, the negative electrode plates of the cell element in the negative terminal cell electrically connected to a negative terminal, the electrode plates of each cell element electrically connected in series to the electrode plates of opposite polarity in the adjoining cell by at least two intercell connectors;
and sulfuric acid electrolyte in contact with the positive and negative electrodes and separators in each cell, the size and total number of grids, the mass per unit area of each grid, the mass of paste per unit area, the manner of electrical connection cell-to-cell and the weight of electrolyte used being coordinated to provide a battery having an average resistance-lead weight equivalent on a per cell basis, measured at 0°F, of no more than 3.3 milliohm-pounds and cola cranking amps of at least about 30 amps per pound lead.

46. A battery as set forth in claim 45, wherein said electrode plates positioned in each cell are perpendicular to said partition.

47. A battery as set forth in claim 46, wherein an element strap electrically connects in parallel plates of like polarity in each cell, said element strap being generally parallel to said cell partition and having a length .
substantially equal to said cell partition.

48. A battery as set forth in claim 47, having a total of at least 24 electrode plates.

49. A battery as set forth in claim 48, each electrode plate having a surface area of from about 5 to 10 square inches.

50. A battery as set forth in claim 45, wherein said battery has an average resistance-gross weight equivalent on a per cell basis, measured at 0°F, of no more than 4.9 milliohm-pounds and cold cranking amps of at least 16 amps per pound based upon the weight of the battery.

51. A battery as set forth in claim 45 wherein there are at least three intercell connections, said intercell connections being fused, through-the-partition connections,

52. A battery as set forth in claim 47, wherein said electrode plate-to-element strap connections are fused connections and there are at least three intercell connections, said intercell connections being fused, through-the-partition connections.

53. A lead-acid battery comprising a container having a plurality of cells having at least one partition wall, said plurality of cells including positive and negative terminal cells, each cell containing a total of at least 24 alternating positive and negative electrode plates positioned perpendicular to said partition wall, separated by separator means and constituting a cell element stack, each of said plates having a surface area of from about 5 to 10 square inches and comprising a grid having active material pasted thereon, the positive electrode plates of the cell element in the positive terminal cell electrically connected to a positive terminal, the negative electrode plates of the cell element in the negative terminal cell electrically connected to a negative terminal, the electrode plates of each cell element electrically connected in series to the electrode plates of opposite polarity in the adjoining cell by at least two intercell connectors; and sulfuric acid electrolyte in contact with the positive and negative electrodes and separators in each cell, the average internal resistance of a cell of said battery, measured at 0°F, when multiplied by the lead weight per cell, not exceeding 3.3 milliohm-pounds, said battery having a peak power of at least about 280 watts and cold cranking amps of at least about 30 amps per pound lead.

54. A battery as set forth in claim 53, wherein said average internal resistance of a cell of said battery, measured at 0°F, when multiplied by the total cell weight, not exceeding 4.9 milliohm pounds, said battery having a peak power of at least 200 watts and cold cranking amps of at least about 16 amps per pound based upon the weight of the battery.