US2849522A - Electrical accumulators - Google Patents

Description

Aug. 26, 1958 P, GARINE v 2,849,522

ELECTRICAL ACCUMULATORS Aug. 26, 1958 P. GARINE ELECTRICAL ACCUMULATORS 4 Sheets-Sheet 2 Filed NOV'. 2, 1955 INVENTOR; PHUL GHRINE BY @M Agent Aug. 26, 1958 P. GARINE 2,849,522

ELECTRICAL AccuMULAToRs Filed Nov. 2, 195s l 4 sheets-sheet :s

IN V EN TOR.

PAUL GHRINE Hgmt Aug. 26, 1958 P. GARINE 2,849,522

ELECTRICAL. AccUMuLA'roRs 168 E 152 "Lm M368 INVENTOR.

. PHUL GHRINE BY Ayant United States Patent O ELECTRICAL ACCUMULATORS Paul Garine, Paris, France, assignor to^Yardney International Corp., New York, N. Y., a corporation of New York Application November 2, 1953, Serial No. 389,817

Claims priority, application Switzerland November 11, 1952 4 claims. (ci. 1364143) This inventionrelates to improvements on electrical accumulators. It particularly applies to accumulators in which at least one electrochemically active substance is in divided form; 'means having thus to be provided to preventsaid substance from wandering towards another active substance having a different polarity, which would result in internal short-circuits.

In such accumulators, particularly in those whose operation has been found to Vbe advantageous when the electrochemically active media is under pressure, it has been suggested to interpose, between active substances having diiierent polarities, separators or diaphragms consisting of one or several thin sheets of a semi-permeable material, such as regenerated cellulose, or cellophane.

It has been suggested to either fold or wrap sheets of cellophane, or such like, around electrochemically active substances, so as `to enable the evolution of the gases as might develop in the course of some phases of the electrochemical reactions.

Although such accumulators, the most noted of which at present is the silver-zinc accumulator, operate quite satisfactorily in many an application, it takes a great deal of skillful manipulating to manufacture them, and however carefulis such manufacture, it is not always possible, when folding the sheets, to avoid the formation of zones of least resistance, the latter developing in the course of the accumulators operation into j cracks or rips through which the active substance is liable to wander. At any rate,` this is how the applicant accounts for certain discrepancies in the results obtained with .such accumulators.

One object-of the invention is to provide an accumulator in which ione' active substance at least is ina divided for-m, and which is free of internal short-circuits, even after the cell has been in` use for a long period, thelife of said accumulator computed in cycles (successions of charges and discharges) being a very long one.

It is also an object of the invention to provide an accumulator in which all and any risk of explosion is eliminated, even under the most exacting operating conditions, and which in this respect may be `utilized inA such fields where it is vessential to achieve perfect safety with regard to risks of explosion.

Another object of the invention is to'provide an accumulator having semi-permeable partitions or separa* tors, the manufacture `of which is extremely simple and liable to be executed along mass production lines, the various accumulators of said mass production being all high-grade units, without the necessity for taking special precautionary measures' andexcluding any rejects.

lt is also an object of the invention to provide an accumulator in which the container is to be utilized actually to almost the full of its capacity for the development of the electrochemical reactions, the power-weight ratio of the accumulator thus being a high one.

It is also an object of the invention to provide an accumulator in which some essential parts can be reegg a..

moved andreplaced, if need be, While the other parts can continue to be used.

Another aim of the invention is to provide an ac# cumulat-or whose electrolyte can be renewed after a certain time in operation, thus improving the period in service of the cell.

According to the invention, the active substances having diierent polarities, one of which at least is in a divided form, are contained in compartments separated the one from another by rigid or relatively rigid partitions, or walls or separators, allowing the electrochemical relations to take place, said partitions being joined with the container 'by means of a tight connection.

In such an accumulator, the evolution of the gases liable to develop in the midst of the active substance is easy, because said substances are not wrapped.

ln one embodiment, the independent compartments are `in communication with the atmosphere through independant conduits; the escaped gases, of different natures, are thus prevented to mix the one with another.

According to the invention, also, a separator consists of a semi-permeable sheet joined side by side with a rigid or relatively rigid support, perforated or not, of semiper-meable or not semi-permeable material.

Another feature of the invention yis the application, as separator, in'an accumulator ofthe above mentioned type and particularly in ay silver-zinc accumulator, of a plate or plaquette of wood or similar material.

As a result of its expansion under the action of the electrolyte, this plate contributes to the creation and preservation of the internal pressure. It can be used alone, its thickness being so selected that the suitable degree ofV semi-permeability may be obtained.

It can also be usedA joined side byside with a sheet of cellophane, or similar material. In this respect, the invention provides an embodiment in which a sheet of semi-permeable material, such as cellophane, is ilanked on either side by a plate or plaquette of wood.

In an accumulator comprising such a separator, one and/or the other active substance is not in effective contact with the sheet of semi-permeable material. This denitely-prevents the sheet of semi-permeable material from being attacked by one of the active substance and especiallyv silver, thus improving on the life of the accumulator.

In the following description, given withoutl limitative character, reference is made to the appended drawing, in which:

Fig. 1 is a vertical section through an accumulator as per. the invention, the section fbeing parallel to a separator;

Fig. 2 is a section along the line 2 2 of Figure-1;

Fig. 3 is a sectionfalong the line 33Yof Figure 1;

Fig. 4 is a view similar to Figure 1, but for another embodiment;

Fig. 5 is a view from above, with the cover removed and some parts being broken away;

Fig. 6 is a section along the line 6 6 of Figure 4;

Fig. 7 shows a section through a separator, on a larger scale;

Fig. 8 is a view similar to Figures 1 and 4, but for still another embodiment;

Fig. 9 is a section along the line 9--9 of Figure 8;

Fig. l0 is a section along the line `10-10 of Figure 8;

Fig. 11 is a view from above of the cover, on a smaller scale;

Fig. 13 is a section along the line 13--13 of Figure 12- Fig. 14 is a section lalong the line 14-14 of Figure 12;

Fig. is a perspective view of a constituent part of the accumulator as illustrated by Figures 12 to 14;

Fig. 16 shows another constituent part in perspective;

Fig. 17 shows yet another part in perspective.

Reference is first made to Figures 1 to 3. In this embodiment, the accumulator with which the invention is concerned comprises a parallelepipedal container 20 made of plastic, consisting of large sides 21, 22, small vertical sides 23, 24 and of a bottom 25. The vertical sides 21- 24 are made slightly thinner at their upper end in order to provide a rim 26 for supporting a cover 27 consisting of a plate of plastic having two perforated projections 28 and 28 for letting the electrical connections through, also a central nipple 30 which may be stopped up with a plug and whose section inside the container acts as a detlector, said central nipple being for the purpose of allowing the gases out and feeding the electrolyte in. The cover bears two ribs 29 and 29', higher than the internal section of the central nipple 30, whose function will be explained later.

Inside the container is arranged a strip or tape 31 of spongelike rubber, or similar material, whose vertical sections 32 and 33 thus line the internal surface of the walls 23 and 24, while the horizontal section 34 lines the internal surface 35 of the bottom 25. The ends of the tape 31 are fairly flush with the rim 26. Inside the container are located a number of rigid or relatively rigid partitions 37 placed in a parallel arrangement and made of a semi-permeable material or of a material which may be looked upon as semi-permeable when having a suitable thickness. The easiest arrangement is to make the partitions 37 out of wood. The shape of these partitions is a fairly rectangular one, with the upper edge however possibly polygonal, as shown at 38. The partitions 37 are larger in width than the distance between the opposed faces 39 and 40 of the tape 31, the difference in width being such that when introducing the partitions into the container, said partitions bring about an elastic deformation of the tape 31, with their vertical marginal part 40 going deep into the rubber or similar material, the depth to which the partitions thus penetrate possibly being a substantial proportion of the tapes thickness. This develops a comparatively high compression stress between the tape of spongelike rubber and the partitions 37, said compression exerting itself not only against the edge 40 of a partition 37, but also between the marginal sections 43 and 44 of said partitions. In addition, when placing the cover 27, the ribs 29 and 29 press down the upper part of the partition 37, so that the lower edges of the latter partition go deep into the horizontal section 34 of the tape made of spongelike rubber or of a similar material. The partitions 37 thus delimit in the container a number of compartments 45 into which the active substance is fed, for example in turn cakes of zinc oxide in comminuted form and comminuted silver. The conductors coming out of these cakes are tied together into bundles according to their polarities, in well known manner, both bundles being led out of the unit through the projections 28 and 28'. The whole unit is impregnated with electrolyte, in this particular instance a concentrated watery solution of ziucate of potassium, and this simple arrangement gives an electrical accumulator With a long life in service, viz. one that may be subjected to a comparatively large number of cycles without losing its electrical qualities.

Reference is now made to Figures 4 to 7. In this embodiment, the container 50 is also of parallelepipedal shape, having small vertical outer walls 51, 52, large vertical walls 53 and 54 and a bottom 55; the upper edges of the vertical walls are made thinner, into a peripherie step 56 supporting a container 57. Inside the container 50 is arranged a strip or tape 57' of spongelike rubber or of a similar material, the vertical sections 58, 59 of which thus line the inside surfaces of the walls 51 and 52, while its middle section lines the inside surface of the bottom 5S. Inside the container are introduced a number of partitions 61, two of them in the specific example shown, whose width is such that they strongly compress the spongelike rubber, as described above, thus ensuring a good tightness between the various compartments, with regard to the wanderings of active substance, even in divided form. In each compartment thus delimited is placed a frame 63 made of plastic, in the general shape of a U,'consisting of two vertical branches 64 and 65 and of a horizontal section 66. The upper end of the branches 64 and 65 is cut out, thus providing a step 67 supporting a compartment cover 68,-the latter having a hole 69 through which a connecting conductor is driven, also a hole 70 for the purpose of allowing the gases to escape. The cover 68 is also shown arranged with a projecting part 71, the purpose of which is to facilitate the removal and setting in of the cover. As for the outerrnost compartments, the frame 63 is anked on one side by an outer wall such as 54 and on the other side by a partition 61; as for intermediate compartments, the frame 63 is flanked on either side by a partition 61.

In the embodiment as illustrated, each partition 61 consists of two joined plaquettes of wood 72 and 73, or similar semi-permeable separator, rigid or relatively rigid, between which is inserted one or several sheets of a semipermeable material 74, such as cellophane. On the cover 57 are two connecting terminals 75 and 76 which accommodate the conductors coming respectively from the positive or negative compartments. The cover is also provided with a channel 77 for the purpose of letting the gases out and lling the electrolyte in, said channel being bored through a projection 78 ending in a chamber 79 which can be capped with a stopper 80 provided with an opening 81. In addition, the cover is provided with two ribs 82 and 83, for instance molded-on ribs, slightly higher than the projection 78, in order to rest on the upper edges 84 of the partitions 61, thus keeping the partitions lower edges 85 tightly pressed against section 60 of the spongelike rubber; this ensures a continuous impervious belt al1 around each compartment.

In the preceding gures, there has been illustrated an active material (indicated at 62 in Fig. 6) connected by suitable leads to positive and negative terminals such as those shown at 75 and 76 in Fig. 4. In the embodiment disclosed hereinafter the active material and its terminal leads have been omitted to afford a better view of the structure of the electrode compartments.

Reference is now made to Figures 8 to 11 concerning another embodiment. The container is of parallelepipedal shape, being enclosed by vertical walls 101, 102 and 103, 104. In this embodiment, the partitions are placed in the mold prior to molding the plastic, so that after molding the vertical edges 106 and 107 of said partitions, as well as their lower edge 108, are sunk in said plastic, thus achieving without further process the necessary degree of tightness between the compartments they delimit. Prior to molding, a tape 109 of spongelike rubber or similar material may be inserted as indicated on the figure, so that it should cooperate with both the vertical and lower edges of the partitions 105. It is well to make up each partition of two wooden plates or the like, joined together (110 and 111), between which is inserted one or several sheets of a semipermeable material such as cellophane. The walls 101-104 are provided with steps, thus constituting peipheric resting surfaces 112 for covers 113, each cover corresponding to a specific compartment. Each cover is provided with a nipple 114 for the purpose of providing outlets to let lthe connecting conductors through, also with a central perforated projection 116 enclosing a chamber 117 and serving as a vent tube for the covered compartment; the upper part 118 of the projection goes through an overall lid or cover 120, the latter being provided with holes through which are inserted the upper sections 121 of the parts 118; as a result, each compartment is independently connected with the outer atmosphere. The cover is provided with two projecting parts 122 and 123 for the purpose of letting the connecting conductors through. At its periphery, the cover rests on a step 124 at the upper ends of the vertical walls.

Reference is now made to Figures 12 to 17, showing yet another embodiment. The accumulator comprises a parallelepipedal container having two small vertical walls 151 and 152, and two large walls 153 and 154, which are made thinner at the top, thus forming a step 155 on which rests an overall cover plate 156. Against the wall 154 is placed a member 157 (Fig. 15) made of plastic and consisting of a bottom 149 and of two peripheric ribs 158 and 159; against the ribs is applied a frame 160 (Fig. 16) made of spongelike rubber or of a similar material, in the shape of a U, consisting of two vertical branches 161 and 162 and a bottom part 163. Against the frame is applied a partition or separator 164 consisting of two wooden plaquettes 165 and 166 between which are inserted one or several sheets of a semi-permeable material 167. After the partition 164 comes another rubber frame 160 identical with the frame 160; on the other side of frame 160 is arranged a spacing member 168 in the shape of a U (Fig. 17), made of plastic and having two vertical branches 169 and 170 and a bottom 171. After this spacing member comes another frame of rubber 160 after which comes a partition 164' etc. The whole arrangement thus made up and kept under pressure is introduced into the container, thus obtaining several compartments 172 which are impervious in relation to one another with regard to the wanderings of active substance. Each compartment is sealed by its own cover 173 resting on steps 174 and 175 provided at the top of the members 157 and 168; through each cover 173 is bored a hole 176 for the purpose of letting the conductor through, also a hole 17'7 for allowing the gases to escape.

What I claim is:

1. In an electric battery, in combination, a casing having a bottom and sides, rigid electrolyte-syvellable inter-electrode separator means dividing said casing into separate electrode compartments, and resilient retaining means secured to said casing along the bottom and sides thereof, said retaining means yieldably engaging said separator means along the lower and lateral edges thereof, thereby forming a continuous seal along said edges while enabling swelling of said separator means.

2. In an electric battery, in combination, a casing, rigid electrolyte-swellable inter-electrode separator members dividing the casing into a plurality of separate electrode compartments, a strip of resilient material extending along the edges of each separator member, means including said resilient strip for positioning and sealing the lower and lateral edges of each separator member in said casing, and an individual cover for each of said compartments, the upper edges of said separator members being held in position by pressure exerted upon it by the respective covers via said resilient strip, thereby providing substantially sealed compartments.

3. In an electric battery, in combination, a casing having a bottom and sides, rigid electrolyte-swellable interelectrode separator means dividing said casing into separate electrode compartments, covering means substantially isolating said compartments from one another and from the outside, and resilient retaining means secured to said casing along the bottom and sides thereof, said retaining means yieldably engaging said separator means along the lower and lateral edges thereof, thereby forming a continuous seal along said edges while enabling swelling of said separator means.

4. The combination according to claim 3, wherein said covering means includes individual covers for said compartments, said covers being provided with individual vents for gases escaping from said compartments, and a lid overlying said covers, said lid having pores aligned with the vents in said covers.

References Cited in the le of this patent UNITED STATES PATENTS 1,088,210 Davis Feb. 24, 1914 1,419,396 Manwaring June 13, 1922 1,691,794 Woodbridge Nov. 13, 1928 1,712,822 Hebbeler May 14, 1929 1,884,071 Menzel Oct. 25, 1932 1,902,267 Rupp Mar. 21, 1933 2,511,887 Vinal June 20, 1950 2,585,564 Lubeck Feb. 12, 1952 2,594,710 Andre Apr. 29, 1952 2,610,219 Yardeny Sept. 9, 1952 2,654,794 Zaugg Oct. 6, 1953 2,704,781 Mautner et al. Mar. 22, 1955 FOREIGN PATENTS 1,654 Great Britain Feb. 2, 1887

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