DE2243187A1 - CATHODE FOR GALVANIC ELEMENT AND METHOD OF MANUFACTURING IT - Google Patents

Description

Cathode for galvanic element and process for their manufacture

The invention relates to rolled cathodes for galvanic elements and processes for their production.

It is known that large electrode areas and high performance characteristics are obtained with rolled cylindrical battery elements. In such elements or cells, layers of anode and cathode material are used, which are wound spirally between layers of an absorbent separator material impregnated with the electrolyte. The anodes and cathodes are formed by a thin conductive material, which can be an electrochemically active material or, especially in the case of cathodes, a conductive carrier for ¹

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active material is. U.S. Patent 2,536,699 shows an example of such a cell.

Norinalerv / else is the active material of cathode, a solid, usually a metal oxide, sulfide or salt ^1, beispielsv / else a halide. Such masses are brittle and inelastic at their maximum bulk density and there is a risk that they will splinter or crumble as a mass when deformed. With a reduced bulk density, for example in a porous form such as is used for large surface contact with liquids, this risk is increased.

U.S. Patent 3,432,351 describes the preparation sintered plates of active electrode material in open pockets of conductive mesh about 0.5 to 2.5 mm (about 0.02 to 0.1 ") thick, around a To obtain a rollable electrode made of crushable material, which is held in the cavities of the grid. Although the grids are described as being highly flexible, they nonetheless exhibit resistance to flexing the thickness of the grid, so that the resulting electrode is difficult to roll. It also gives the electrode a low level of efficiency, which is due to a relatively large proportion of the carrier is required for the active material and exists in some active material the tendency to detach from the mesh material when it is bent.

The inelastic behavior of the mentioned active cathode materials seriously affects the structural Ge :; Ia] -ung and makes the assembly of a rolled cell difficult. Active material on a cathode base must not be so thick that when the B:.; Is bridge] L

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and thereby the efficiency of the cathode is limited. This enables the assembly of cylindrical cells made complicated and expensive.

U.S. Patent 3,485,677 describes the adaptation an alkaline modification of the Leclanche cell for a rolled cell using a carbon cloth, its openings with a paste of an electrolyte and a suspended active cathodenina are filled. Although with such a cathode structure, there are problems of active material breaking down are avoided is the electrical contact between the active Kathodenina material and the current-carrying carrier somewhat limited so that little utilization of the cathode active material is obtained. A similar cathode design is shown in U.S. Patent 3,455,739 in which sintered active material is made from a Gauze is worn.

The amount of active material that does not crumble out of a cathode base during bending can thereby be increased v. that it is applied to the base mixed with a binder, as in the U.S. patent 2,536,699 stated. However, a binder increases this. Material cost and reduces the electron discharge speed the cathode in that the active material is thinned and the surface of the material against the contact with the electrolyte is blocked.

Require such binder restrictions the use of excess cathode active material on a flexible cathode base. If such an ineffective cathode must be used, so do so to the effect that the performance characteristics of a rolled

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Battery element using such a cathode is limited by the fact that the active material, that can be used in the available space of a cylindrical battery is limited.

Another disadvantage of known rolled electrodes is the inherent elasticity of their base materials. If a rolled assembly is placed in its container, there is a risk that the base material due to the elasticity, springs slightly open. This creates the desired equal and narrow spacing the cathode disturbed by the anode, so that the cell's ability to maintain a high current discharge something is lost. U.S. Patent 3,364,069 describes a method and a device for solving this assembly problem. However, that cause The time and equipment needed to solve the problem is quite a cost.

The invention provides a cathode for a galvanic element made of hinged segments, in which a flexible electrically conductive sheet material is in intimate electrical contact with a number of adjacent segments made of normally inflexible active cathode material, which segments are formed by grooves of sufficient width and Depth so that adjacent segments can be displaced with respect to one another to form a spiral coil, but remain in electrical contact, and at least a portion of the cathode material of adjacent segments is brought into closer proximity ¹ without loss of active cathode material. A continuous process for the production of the segment-shaped cathode is described, in which the conductive Folierimateria.1 and the active

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Cathode material are conveyed through the gap of opposite pressure rollers with transverse ribs, which, if the rollers are rotated come into a position in which they face each other.

The invention also provides a flexible cathode made from normally non-flexible cathode material which can be rolled into a spiral shape without the cathode active material from crumbling get lost.

In the accompanying drawings show:

Fig. 1 is a perspective view of a typical inventive fäthodenform;

2 shows a view in section on an enlarged scale along the line 2-2 in Fig. 1;

3 shows a perspective view of a further embodiment the cathode according to the invention;

4 shows a view in section on an enlarged scale along the line 4-4 in Fig. 3;

Fig. 5 shows a preferred method of manufacturing the cathode of Fig. 1;

Figure 6 is a sectional view of a typical rolled

Bundle that has a cathode according to the invention, * contains an anode and separators;

Figure 7 is a sectional view of a typical rolled

Bundle that has a cathode with curved segments

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of graduated radiuses.

The cathode according to the invention is made of a strip adjacent segments of a normally inflexible active material, the adjacent segments hingedly together by a flexible conductive sheet-like base extending through the segments are connected, with parts of the segments that are adjacent to the articulation, are free of material that splinters or crumbles when a segment is pivoted. The segments of the strip usually have an im substantial constant maximum thickness and can be made from a cohesive, electrochemically active, usually inflexible electrode material are produced. For a better understanding of the invention, it is described below described with reference to the accompanying drawings.

1 and 2, in which a cathode shape according to the invention is shown, show a contiguous strip of adjacent segments 1 of normally inflexible active cathode material which surrounds a contiguous, flexible, electrically conductive foil base 2 which extends contiguously through the contiguous segments. In this embodiment, the film-shaped base 2 has continuous cavities which enable a cohesive force of the cathode material on both sides of the film in these cavities. The term pliable or flexible as used here is to be understood as meaning that the material glue, bending, does not break and is preferably pliable compared to the material of the segment. Transverse grooves 24 extending across the strip substantially parallel to one another ,

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distinguish adjacent segments from one another. These grooves have a depth up to the foil-shaped base 2 and are sufficiently wide that the segments on either side of each groove are bent with the base 2 as a hinge can to bring the active cathode material of adjacent segments in greater proximity without active Material is lost through crumbling when the segment strip is brought into the form of a tight spiral.

3 shows a further cathode for ¹ ITi according to the invention with a series of arcuate segments made of normally non-flexible cathode material 8-12, which are connected to one another along adjoining lines 3-6 by a coherent, flexible, electrically conductive film-shaped base, as at 14 in FIG. 4, which base extends contiguously through the arcuate segments and adjoining lines. FIG. 1 shows, on an enlarged scale, a sectional view through the structure obtained with more details and the extension of the base 14, likewise with continuous hoops, in continuous form through the arcuate segments and forms an articulated connection between them. The arrangement shown can be used to form a cathode around the articulated connections along the angular lines 3, 4, .5 etc. to form a cathode.

The radius of these arcuate segments can be kantinüierlnca from the one joint line of a segment can be changed to its nearest joint line. In. . dar *, 'however, it is most useful to J-ön-b'iaiiten mean radius of curvature in a segment, to twist "

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5- shows a preferred method for producing the cathode according to FIGS. 1 and 2. In this method, a porous, coherent, flexible, electrically conductive, sheet-shaped base 15 is continuously moved into a loading zone 16. The loading zone 16 is further supplied by a source 17 _# particulate with a stream of cathode active material 18 and is bounded by cylindrical pressure rollers 19 and 20 which rotate in the indicated directions. The pressure rollers 19 and 20 are provided with axial roller ribs 21 and 22 which are arranged in such a way that successive pairs of these are opposite one another when the roller surfaces are closest to one another.

The moving speed of the base 15, the feeding speed of the particles 18 and the peripheral speed of the ribs 21 and 22 are coordinated so that the product exiting between the ribs 21 and 22 is a continuous strip that corresponds to its shape corresponds to the cathode shown in Figs.

In Figure 6, which is a sectional view through the axis of a typical rolled cell, not to scale shows an electrode according to the invention is shown. The bundle shown consists of an anode foil material 25 which is supported by an absorbent separator foil 2 is included, which is connected to the cathode strip 27 of the type shown in Fig. 2 is wound in a spiral shape so that separator material between alternating layers of the anode and the cathode is obtained.

In Fig. 7, in which a further inventive

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Cathode is also a sectional view through the axis of a typical rolled cell bundle shown. In this bundle, an anode foil material 25 is also used, which is enclosed by an absorbent separator foil 26. The cathode 2 8 is defined by a series of hinged arcuate segments of stepped radii of curvature, such as shown in Fig. 3 and 4, the radii of curvature are graduated so that they are between the K ± hodenma.teriallagen enclosed anode material are precisely adapted,

The purpose of this cathode training is to provide a substantially uniform distance between the cathode material and the anode material with which it is rolled Wix ⁿ d, maintained at, and new advantages of the amount of the cathode active material, .the is able to respect the electrical discharge is available, and the easy assembly of the rolled cell without difficulty through elastic resilience.

The cathode of the invention can be rolled as a series of flat segments, with limitations in terms of width consist of that of the curvature depend on which the series follows. With a rolled cell, segments of constant width 75 to 120 ° can be one Cover the circular arc in the middle of a roll, gradually increasing the overlap to 12 - 10 ° of a circular arc decreases on the outer part of a role. Flat segments are because of the simplicity of their formation and their suitability for assembling a variety of rolled cells is preferred.

The dimensions of the cathode made up of flat segments are

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in the sectional view of FIG. 2 with d. , d ₂ , dg, d ₄ and dr. The following ranges are given for the relationship between these dimensions:

dr a thickness range from about 0.025 mm to about 0.50 mm (from about 0.001 to about 0.020 "), preferably from about 0.25 mm to about 0.38 mm (from about 0.010 to about 0.015"), but always less than d _t .;

d ₂ a range from 10 to 100%, preferably 15-25% of d .;

d ^ a range of about 1/3 from dr to 50%, preferably 20-15%, of d ~;

2 a range of 10 - 50%, preferably 20% to 50%, from d ~.

Typical dimensions of the segments in millimeters (or in Inches) of a continuous strip of such segments for use in "C" and "D" size cells as follows:

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Variations Ci ₁ d ₂ d _g d ^ d ₅

I - 2.667mm 0.508mm 1.118mm 0.508mm 0.355mm " k

(0.105 ») 0.020") (0.044 ") (0.02.0") (0.014 ") ^

II - 2.565mm 0.610mm 2.286mm 1.270mm 0.381mm

(0.101 ") '(0.024") (0.090 ") (0.050 ·') (0.015")

2 III - 3.175mm 0.889mm 2.286mm 0.508mm 0.355mm

2, (0.125 ") (0.035") _(0? 090 ") (0.020") (0.014 ")

_ * j IV - 3.175 mm 0.508 mm 1.143 mm 0.127 mm 0.355 mm

2 (0.125 ") (0.020") CO.045 ") (0.005") (0.014 ")

V 3.175mm 0.305mm 0.762mm 0.381mm 0.355mm

(0.125 ») (0.012") (0.030 ") (0.015") (0.014 ")

0R-51S1

For larger cells, however, these dimensions can be larger be.

Cathode strips for rolled "C" size cells require transverse grooves to prevent crumbling of cathode material when the thickness d ₃ of FIG. 2 exceeds 0.50 mm (0.020 "). Rolled" C "size cells have one Outside diameter of the spiral electrode roll of about 2.54 mm (about 1 "). The. critical strip thickness before transverse grooves have to be used, for larger or smaller rolls is accordingly larger or smaller.

The arc coverage amount can be rolled with a Cell be larger if the segments are circular arc-shaped. The segments can have the same circular arc consecutively and be wider than the flat segments that are used for could be used for the same purpose.

As shown in Fig. 3, the arcuate segments be so graduated in their curvature that they practically form a series of rigid circular arcs, which when they are around their articulations are pivoted around, can press evenly against the anode and separator, which between the layers of the spiral cathode are arranged. The segments can be considered as successive parts of a perfect Spiral with a constantly increasing circular arc radius be cast in each segment, but in practice it is preferred that the middle one for each segment Radius of a circular arc segment is used over the entire segment.

The largest feasible arc coverage amount in of a rolled cell is by a curved segment

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180 °. Typically, if you have a series of stepped circular arc-shaped segments, the segments for the inside of a cell roll is provided for up to 180 ° arc coverage per segment and less coverage s amounts of for example for the sere of a cell roll.

cover amounts of, for example, 120 ° for segments

One extends through each segment of this cathode flexible conductive foil material through and into the next .segment. For the sake of lower weight and the easier assembly, the sheet material can be manufactured with through-void spaces. This Base material, a conductor for the active material of the segments, enables adjacent segments can be bent at the bottom of the grooves without detaching the active material of the segments or the foil material breaks. Usually it is so easy with respect to the amount of active material in the segments, that its resilience when bending adjacent segments is negligible. Preferably has the sheet material .50% or more through voids, so that the active material through its cohesion is maintained in contact through the sheet material, the required thickness of the sheet material can be easy according to the necessary strength and the preferred over the active .Material of the segments Determine flexibility. For cathodes for cells of the commercially available "C" size, the foil material a thickness of 0.025 mm to 0.50 mm (0.001 "to 0.020") have, while for larger and smaller cells these dimensions change accordingly. As a result of that relatively little base material is required, a high cathode efficiency is obtained.

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The hinge effect of the base film is supported by the grooves, which are adjacent segments of the active Separate materials from one another. The material should be missing at the grooves so far that a segment around its articulation can oscillate without the active material of adjacent segments experiencing such a pressure that a Loss of active material due to crumbling occurs. Some cracking is allowed if the active Material does not lose electrical contact.

The invention extends to the use of any cathode active material applicable which tends to splinter or crumble when there is a mass of this material is deformed. Almost all inorganic oxides, sulfides and salts have this tendency. For example materials are copper sulfide, iron sulfide, silver chloride, silver oxide, nickel oxide, lead peroxide and the reaction product of sulfur and copper as described below. Such materials can be used alone or mixed with other cathode-active materials Materials are used. Preferred materials for these cathodes are copper (II) sulfide and Ferrous sulfide.

Copper (II) sulfide can easily be used for the purposes according to the invention. Copper in the form of particles ranging in size from 50 to 200 microns can be intimately mixed with sublimed sulfur in an S / Cu atomic ratio of 1/1 to 1.1 / 1 and stored at a temperature of about 20 C to a temperature , are aged 60 ⁰ C - below the melting point of sulfur, preferably twentieth After a time, which depends on the particle size of the copper used, the porosity of the copper and the temperature of the mixture storage, the reaction between the copper and the sulfur proceeds to

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one level of easy compressibility without the application of heat. For example, a mixture of electrolytic copper with a particle size of up to 50 microns and half the weight of sulfur after aging for 10 hours at ^{25-30 ° C. or 20 to 1} hour at 20-25 ° C. can result in a mixture which, if it with 100 to 700 kg each

2
cm pressure is compressed for a few seconds to several minutes, forms a coherent solid mass with such a bulk density that about UO% to 80% of the structure is void.

The completion of the reaction in the aged mixture can be achieved by heating it to an elevated temperature of preferably up to 200.degree. the Reaction is complete, usually but not necessarily, after the aged mixture is densified. the compacted mass does not sag and does not change its dimensions significantly during heating.

The conductive base material used for the articulation can be selected from a variety of materials including are not anodic to the cathode active material. Such a material can be selected from, for example, the following Line-up can be selected:

Nickel gas sieve perforated nickel foil nickel-plated iron gauze screen copper gauze

perforated copper foil silver gauze sieve.

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Platinum sieve gauze sieve made of rust-proof steel, perforated silver foil perforated platinum foil perforated foil made of rust-proof steel

silver-plated glass fabric through sprayed-on silver paint

silvered glass fabric by aqueous electrochemical reduction of silver salts

silvered glass fabric by coating with silver oxides, thermally dissociated,

silver-plated glass fiber flake mat through sprayed on Silver color

Silver-coated fiberglass mat by watery electrochemical reduction of silver salts

silvered glass fiber flake mat by coating with silver oxides, thermally dissociated

Silver-plated nylon fabric with sprinkled silver paint

Silver-plated nylon fabric by aqueous electrochemical reduction of silver salts

Fabric made of silver and glass threads as warp and weft (Mixed fabric)

Fabric made of threads made of rust-resistant steel and glass as warp and weft (mixed fabric)

The electrode according to the invention can be according to various

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Process are produced. In one method, a coherent mass of cathode-active material, through which a base material extends, for example formed by casting or pressing particles and later by compacting or removing cathode-active material along the intended hinge lines notched or grooved »Preferably, the electrode can be made by compressing particles active material around the conductive sheet material between ribbed parallel dies, the Segments result one after the other or in groups, at the same time the segments with joints and grooves be formed along the hinge lines.

A preferred method of making flat segments is shown in FIG. In the device for this method, two pressure rollers of the same diameter are provided, each of which is provided at equal intervals with axial circumferential ribs which revolve so that successive ribs of each roller face each other at the point of their closest approach. The distance between the opposite ribs at the point of their closest approach can be smaller than the thickness of the conductive foil material, as long as the foil material is not severed, but is preferably greater than this thickness. For "C" and "D" cell cathodes this thickness is in the range of 0.025 ¹ mm to 0.25 90 mm (0.001 "to 0.01020"), preferably 0.254 mm to 0.3 81 mm (0.010 "to 0.015 ^l! ) The distance between the roller surfaces determines the thickness of the segment to be produced,

When performing the method, a continuous strip of conductive sheet material is between

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the rollers provided with ribs are fed at the peripheral speed of the roller surfaces. A loading zone for active cathode material to be compacted on the sheet material is between the rollers where they meet approach closest, provided and limited by retaining elements at the end of the ribs. Particles of cathode active Material is metered into this loading zone while the film material is being conveyed through this zone. If that Foil material much more than 50%, for example 90%, has continuous cavities, the supply of particles can often only take place on one side of the film material, since the uncompacted particles easily pass through the voids. During the passage of the particles and the sheet material through the point of closest approach v / ground the particles on the base material while simultaneously Formation of the joint or border lines between the segments through the gap between the opposing segments Compacted roller ribs.

In this electrode material, the base material is centered, which is a desirable feature for the best Contribution of a cathode to a long lasting high yield represents charge current in a battery cell. The electrode can be subjected to any further treatment desired are, for example, a heat treatment, or collected directly on a roll. You can be light Handling when assembling a rolled cell can be cut to any desired length.

If the device described is modified in such a way that ribbed pressure rollers of dissimilar Diameter can be used, with the successive ribs of each roller facing each other at the point of their largest Approaching each other face each other and wherein

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if necessary, the circumferential speed of the ribs of the larger roller exceeds that of the smaller roller, the facility modified in this way can be contiguous Create arcuate segments.

The inventive cathode can be a binder for the active material contained in the segments to the extent that is necessary to contain the active material to give a stronger cohesion. Such an amount of binder is less than that which is necessary is to make the cathode active material pliable.

The cathode described is advantageous in rolled cells when used with compatible anode materials and Electrolyte is used, so that an anode / cathode pair is obtained, the electrical potentials and discharge currents that are compatible with the intended use.

Examples: Example I.

A cathode strip made of contiguous flat strips hinged segments was made as follows:

Each ram of two cylindrical steel rolls with a diameter of 12.7 (5 ") and a length of ¹ H, 28 mm (1-5 / 8") has been provided at its periphery with axially extending sharp ribs that a distance of 3.175 mm (0.125 ") apart with the height of each rib 0.305 now (0.012") and the width at its base 0.500 mm

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(0.020 "). The location of the ribs on each roller was designed so that the ribs successively at the point of closest approach to the horizontal Movement opposed to each other and a grooved sheet 1.117 mm (0.04H ") thick was obtained.

A contiguous strip of elongated nickel mesh about 0.355 mm (0.014 ") thick was made made by pulling apart a 0.178 mm (0.007 ") slotted nickel foil, creating a grid with 90% voids was obtained, which was conveyed between the rollers at the peripheral speed of the roller ribs became. Flowing particles with a mesh size of about 0.05 mm (about 300 mesh) of a mixture of two Parts by weight of copper and one part by weight of sulfur, aged at room temperature for two days the space below the grille where the roller ribs approached each other, measured. The flow of particles on the one side of the grille stepped lightly through the grille to fill the other side.

The grid and the particles passed between the rollers through the gap of the opposing ribs and left the gap as rigid masses of compressed particles as successive segments on the grid material. The product, which in the continuous cross-sectional dimensions corresponded to Variation I of the table, was collected on a roll, ^{heated to 200 °} C. and kept at this temperature for one hour under a vacuum of 50 cm (20 ") mercury.

The strip of strips obtained was in lengths of 19 cm (7.5 ") cut, a size suitable for use is suitable in rolled cells of size "C".

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Example II

Further, a cathode strip was made by compressing a particulate, aged copper-sulfur mixture around an elongated nickel mesh about 0.355 mm (about 0.014 ") thick from 0.178 mm (0.007") protected nickel foil using parallel flat dies for compression . Each die was 5.08 cm (2 ") wide and 17.78 cm (7") long and had pointed ribs along its length with a height of 0.508 mm (0 _a 020 ") and a width of .0.610 mm (0.024 ") foot with tip-to-tip spacing 3.175 mm (0.125"). The dies pressed together until their flat surfaces were 2.28 6 mm (0.090 ") apart , while the tips of one die were opposite the tips of the other die, resulted in a strip of the type indicated in the list under Variation II. This strip could be used in cells of size "D".

Example III

A rolled battery cell the size "C" was like follows assembled.

An absorbent spun-bonded polypropylene film with a Thickness of 0.178 mm (0.007 "), suitable as separator material, was made of commercially available film over both sides Lithium with a thickness of 0.660 mm (0.026 "), a width of 41.27 7 mm (1.625") and a length of 25.4 cm (10 ") folded. A 19.05 cm (7.5") long strip

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fening a "C" size cathode strip according to Example I. was placed over the enclosed lithium strip and the two strips were hand wound into a spiral of the type shown in FIG. 6 rolled up. The spiral roll obtained had an outer diameter of 24.89 mm (0.980 ") and showed no tendency to spring apart.

The roll was encased in a cylindrical steel jacket with an outside diameter of 25.4 mm (1.00 ") and a wall thickness of 0.254 mm (0.010 "). The jacket was closed at one end with a steel plate which was electrically connected to the jacket and to the lithium. The role was with an electrolyte of 8.5 square cm a mixture of 70 percent by weight of tetrahydrofuran and 30 percent by weight of 1,2-dimethoxyethane, containing 10% dissolved lithium perchlorate wetted. A plate that carried an electrical contact and exposed to the interior and was electrically connected to the nickel of the cathode, was sealingly insulated from the other end of the jacket used.

This cell was discharged daily for 5 minutes via a resistance of 4 ohms until it reached its discharge voltage dropped below 1.00 volts. Their initial voltage was 2.2 volts.

15.2 hours of discharge were accumulated with an arithmetic Average current value of 388 milliamps and an average voltage of 1.55 volts. The cathode utilization was 61% and 80 watt hours per 0.45 kg cell weight were generated.

Comparative example A.

One alkaline Leclanche "C" cell (Eveready E-93) yielded

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under the same test conditions, a discharge of only 7.9 hours at an arithmetic average current of 27 milliamps 6 and an average voltage of 'I IO ₉ volts and 17.5 VJattstunden per 0.153 kg were produced.

Example IV Use for light industrial pocket lamps

A rolled "C-cell made according to Example III was applied through a resistance of 5.3 ohms for four minutes per hour for 8 consecutive hours discharged every day until the output voltage dropped below 1.00 volts.

The mean value of the output current was during the test 302 milliamps at 1.61 volts on average, with 112 watt hours 0.45 kg each and a cathode utilization of 76% was obtained.

Verff Jeichs example B

For comparison, an alkaline Leclanche ^ D "cell gave (Everready E-95) with a discharge of only U 0hm for M minutes per hour of 8 consecutive hours daily, until the output dropped below 1.00 volts, averaging 280 milliamps and 1.13 volts, being 22.3 watt hours 0.45 kg each and a cathode utilization of 38% was obtained *

Example V

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Use for tape recorders

A rolled cell of the size "C", which according to Example III was established, was discharged through a resistor of 7.5 ohms four hours a day until its voltage to 1.0 volts. The initial voltage was 2.2 volts. The mean value of the current was 210 milliamps and the mean voltage 1.51 volts, 116 watt hours per 0.45 kg and a cathode utilization of 69% was obtained.

Comparative example C

In comparison, an alkaline gave Leclanche "-" "D" cell (Eveready E-95) for a discharge over 5.3 ohms with 2 26 milliamps and 1.20 volts on average 3 8 watt hours 0.45 kg each and a cathode utilization of 63%.

Example VI Cathode made of curved segments

A lower and an upper die were used as cooperating molds for pressing a number of adjacent ones curved segments of a spiral electrode, such as shown in Fig. 3, produced.

A rectangular block 19.05 cm (7 1/2 ") long, one Width of 5.08 cm (2 ") and a height of 6.35 cm (2 1/2") across its width with a number of 10 according to below cylindrical one-off of successive larger radius with overlap in one plane 3.81 cm

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(1 1/2 ") from the bottom of the block. In one level About the length and height of the block was the axial dimension of the successive indentations in such a way related that the X-axis was used as the radial center of the first and smallest recess and the Y-axis has been moved to the plane of the recess intersections. X was the ordinate of a radial center and Y is the abscissa of a radial center. R was the radius of the cylindrical recess with the center (X, Y). The depressions were dimensioned and arranged as follows:

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Indentation 1 X Y R. No. mm mm mm 2 0.000 0.000 3,200 (0.000) (0.000) (0.126) 3 7.2 64 1,320 4,394 (0.286) (0.052) (0.173) 4th 16.7 64 1.930 5,588 (0.660) (0.076) (0.220) 5 28,321 2.565 7.010 (1,115) (0.101) (0.276) 6th 4 2.164 3.150 8.128 (1.6 60) (0.124) (0.320) 7th 58.166 3.759 9.34 7 (2,290) (0.148) (0.368) 8th 76.200 4.775 10,846 (3,000) (0.188) (0.427) 9 96.012 6.401 11.786 (3,780) (0.252) (0.464) 10 116.586 5,639 12.090 (4,590) (0.222) (0.476) 139.192 6.578 13,284 (5,480) (0.259) (0.523)

All material was removed from the block vertically above the indentations.

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An upper die that was vertically movable into the lower die and had a length matching the former, which spanned all the indentations of the lower die was made with a series of 10 cylindrical counter-segments provided in a plane for the coincidence of the plane of the recess intersections of the lower die was intended. The axes of the cylindrical segments followed the same dimension coordinates as in the lower die, but each radius used was 1.448 mm (0.057 ") smaller.

Two flat end plates were used, each on the lower die across the ends of the depressions thereof could be attached.

To make a cathode with these dies, a strip of stretched nickel foil with a width was used 50.80 mm (2 ") as manufactured by Exmex Corp. 5N17-2 / O is put on the market and by pulling it apart a 0.127 mm (0.005 ") offset protected nickel foil with 95% continuous cavities between the lower die and the upper die presses to form a one-piece contiguous series of curved Get Seven. After attaching one end plate, the upper and lower dies became theirs and rotated over their edges so that they rested on the endplate. 28.5 g a powdery mixture aged two days two parts electrolytic copper dust and one part sulfur were added until the space between the molding surfaces was just filled. Then the other end plate was attached, the whole set up on the base of the lower die, whereupon the upper die in its passport-Steliving in the lower die was pressed. After retreating the Obcrgosenks was a contiguous series of curved segments

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the lower die. This row was placed in an oven at 200 ^° C. for one hour under a vacuum of 50 cm (20 ") mercury.

The weight of the segment row treated in this way was 30.2 g. After cooling, the battery cell assembly was ready for immediate use Ready to use.

Example VII

The use of cathodes made from curved segments.

A size "D" battery cell was made as follows:

A strip of commercially available lithium with a thickness of 10.16 mm (0.40 "), a width of 50.80 mm (2") and a length of 304.80 mm (12 ") was enclosed by using a sheet with a thickness of 0.432 mm (0.017 ") from" Tyvek "C-15-20, a commercially available one absorbent sheet material made of polyethylene, folded around the strip.

One end of the enclosed strip went into the cavity of the smallest curved segment of the cathode according to Example 6 is bent. The next segment was in a spiral position entangled, while the enclosed strip is so curved became that it follows its inner curve. After wrapping the enclosed strip around the outside of the different k The pivoting of the following segments followed Segments around the new turn of the included: strip around until finally each segment., the cathode spiralijr, was arranged and the enclosed strip was already two

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30981 1/1028 BADORIQINAL

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. 22Λ3187

Location of segments. For the anode-separator-cathode roll obtained trä; no spring back.

The roll was placed in a cylindrical steel beaker 57.15 mm (2.25 ") in length and with a diameter of 32.51 mm (1.28 ") with a wall thickness of 0.381 mm (0.015"), with between the lithium and the Steel wall there was an electrical connection. 25 qcm one Solution of 7.6% lithium perchlorate and 26.4% lithium hexafluorophosphate in ethyl acetate was added and absorbed into the roll. A plate that has an electrical contact exposed on the outside and electrically connected to the articulation, the cathode was sealed inserted into the other end of the jacket insulated from this. The complete cell weighed 95.7 g.

This cell was discharged with a current of 200 milliamps until the voltage dropped to 1.00 volts. Your initial tension was 2.02 volts. The cell delivered an average voltage of 1.6 volts and an output power of 102 watt hours each 0.45 3 kg. The utilization of the cathode material was 81% based on the CuS.

Example VIII

When repeating the assembly of this cell using a 31.6 g cathode made according to Example VI but carrying 2.9.9 g of the active ingredient, a cell was obtained which upon discharge with 200 milliamps down to 1.2 3 volts resulted in 116 watt hours per 0.453 kg and with a subsequent further one Discharge at 100 milliamps down to 1.20 volts increased their power output to 122 watt hours per 0.45 3 kg, with a mean voltage of 1.66 volts and a tärhoden-

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309811/1028

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utilization of 92.5% was obtained.

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3098 11/1028

Claims (1)

Patent claims: 1. Cathode made of mutually articulated segments for a galvanic element, characterized by a coherent, flexible, electrically conductive film base material (2, IU, 15) in intimate electrical contact with a number of adjacent segments (1, 8-12) made of a normally inflexible one cathode-active material, which adjoining segments are separated by essentially parallel grooves (24) in the cathode-active material and the grooves have a sufficient width and depth _? so that adjacent segments can be displaced with respect to one another to form a spiral roll ", however: stay in electrical contact and bring at least part of the cathode-active material of the adjacent segments closer together without a loss of cathode-active material occurring. 2. Cathode according to claim 1, characterized in that each segment is flat. 3. Cathode according to claim 1, characterized in that the cathode active material adheres to both sides "of the conductive foil base material and the grooves in the cathode-active material are arranged opposite one another. - 31 - 309811/10 2 8 BAD ORIGINAL Cathode according to claim 1, characterized in that each segment is flat, the cathode active material on both sides of the conductive foil base material adheres and grooves in the cathode active material are opposite to each other are arranged, which grooves have a depth that results in a cathode thickness at the groove bottom, those ranging from about one third of the thickness of the conductive foil base material to 80% of the full segment thickness and a width in the range of about 10 to 100% of the flat width of a segment and of about 10 to about 50% of the full segment thickness. 5, cathode according to claim 4, characterized in that the grooves have a depth which is the same as the thickness of the cathode results at the groove base, which is in the range of about 20 to about U5% of the full segment thickness and a width ranging from about 15 to about 25% of the flat width of a segment and from about 20% to about 50% of the full segment thickness. 6. Cathode according to claim 1, characterized in that; the segments of the row arcuate with one of Seg- | ment to segment successively graded curvature, so that the row becomes a preformed spiral can be pivoted. 7. Process for the production of a cathode from a to- ' contiguous series of adjacent segments from I. a normally inflexible cathodically effective | - 32 - j 309811/1028 \ OR-5151 ' Material articulated and electrically connected to one another by a cavity containing, Flexible, electrically conductive foil base material which extends continuously through all segments, characterized in that (a) two axially parallel, adjacent cylindrical rollers are rotated, each of which is provided with spaced apart axial ribs so that when the ribs of the adjacent Rollers are in close proximity to one another, these ribs come to lie opposite one another while they move in the same direction (b) a sheet of base material is conveyed through the space in which the ribs are closest to each other, (c) Cathode active material particles smaller than the cavities in the base material are measured in a zone defined by the ribbed Roll surfaces that move to the narrowest rib position are limited, (d) the particles simultaneously with the base materials by the closest proximity of the adjacent rollers be moved in order to cause a compression of the particles on the base material and the formation of To create grooves in the compressed particles through the ribs mentioned and, (e) the connected cathode from the narrowest point the adjacent roller are led out. 8. The method according to claim 7, characterized in that Rolls of the same diameter are used. - 33 - 309811/1028 ORIGINAL BATHROOM oR-5151 9. The method according to claim 7, characterized in that that same circumferential speeds of the successive opposing ribs are provided. 309811/10? 8 Blank page