DE1596023B1 - ELECTRODE FOR ACCUMULATOR CELLS WITH A POROUS MAT RIZE MADE OF ELECTRIC CONDUCTING MATERIAL IN THE FORM OF CONNECTED HONEYCOMB CELLS - Google Patents

Description

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The invention relates to an electrode for the accumulator and the separator to maintain, but also to lator cells with a porous matrix of current between the electrode and the electrode shield, conductive material in the form connected to one another so that changes in the characteristic honeycombs, the pores of which are large are sufficient to produce shafts of the electrode to be impregnated with an active electrode paste. in that, with the new electrode, the mechanical accumulator cells also represent an important auxiliary strength and technological uniformity to improve the means for storing electrical energy for systems and thus improve the properties of accumulator cells, which are especially housed in aircraft, which are used with the new elec should. An important type of cell that is io trode equipped; This means that the alkaline electrolyte cells are suitable for high performance both at room temperature and energy density, the electrode combinations of at and at higher temperatures in the sizes for example silver and zinc, silver and cadmium order of 100 ⁰ C and more can be achieved, and contain nickel and cadmium. High-performance 15 As a result, the invention also relates to the cells are those cells that can store much more creation of an accumulator cell with a new electrical energy per unit weight electrode, which is particularly suitable for aircraft construction than usual cells, such as cells, has a light weight and a large lead electrode. Number of Cycles That Can Be Charged and Discharged A high capacity cell can develop, for example, 100 to 20 and, on the other hand, at normal ambient temperature -400 watt hours per pound. In addition to the doors, it is absolutely reliable and can work at higher temperatures, especially in extremely important applications in flight. B. in the case of load voltage and a long service life for tools and machine tools, with a large number of charging cycles. TV sets, radio receivers and plat- Finally, it is another purpose of the invention to create tens players and starters, portable X-ray electrodes made of zinc and silver, which have a high capacity device and the like and are particularly suitable for high-performance cells with high energy density , Use in silver-zinc high-performance cells, for example with silver-zinc, nickel-cadmium 30.

Accumulators are the electrodes immediately to be further objects and advantages of the invention

opposite sides of a membrane emerge from the description below,

or arranged by a separator, which has the task of becoming the object on which the invention is based

the electrolyte, for example potassium hydroxide, dissolved with an electrode, which is characterized to keep the electrodes apart- 35 that the diameter of the pores is in the range

and a migration of electrode ions is between 0.23 and 2.54 mm, about 8 to 50 pores

prevent through which the cell short-circuited to 25.4 mm of the length of the die and that

would be. the weight percentage of the metal die is 1 to 10

Such separators can either consist of an organic weight percent of the total weight of the electrode niches or made up of organic materials, 40 makes up.

In general, however, inorganic ones are preferred. A major advantage of the electrode after the Scheider. In general, the electrodes are also the invention consists in the increased capacity and in contact with an electrode screen, for example, increasing the strength properties of the electrode, a nickel screen to which the lead for the structure that is connected by sintering the electrode frame is connected to the electrode terminal. 45 scored. The sintering can, for example, at tempera-An essential object of the invention is doors in the order of about 300 to 800 ° C to improve such electrodes so that they take place or z. B. obtained by sintering a silver A significantly higher capacity, par- electrode which is located in a nickel matrix, particular when they are installed in high-performance cells with high electrical at a temperature of about 300 ⁰ C. energy density. Another object of the invention is to guide the electrode according to the invention, to create an electrode which, when installed in either one or both electrodes, increases the performance of the high-performance cell Cell of a high-performance cell, for example the silver with regard to the output power per weight or electrode and the zinc electrode in a silver-zinc volume unit of the cell is significantly improved. 55 cell have a metal matrix, for example

It is well known that the mechanical a nickel die according to the invention. Consists of electrodes made of zinc or other material. Any electrically conductive material is suitable as a matrix material for the active electrode materials in high-performance cells for high electrical material, energy density is difficult to maintain even at room temperature, which is in the form of a highly porous honey; But it is of special honeycomb structure and has sufficient difficulty to maintain this structure at temperatures where mechanical strength is present. Nickel is suitable ^{to obtain a magnitude of 100 °} C. and more. especially good as a material for the die, especially even if a zinc electrode is brought into direct contact with the separator for both the silver and the zinc, an electrode in a silver-zinc high-performance cell occurs for that the electrode material breaks apart 65 high energy density. Other materials or metals that conduct electricity and are low-conductive at the bottom of the electrode compartment for the die, which is used so that it is extremely difficult to achieve a good, constant contact between the electrode and steel are for example silver, copper, rust-free - and nickel alloys, e.g. nickel

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Chrome alloys. The preferred die metals of electrode material are undesirably significant

are nickel, silver and copper, especially since such metals are reduced.

have better electrical properties than stainless steel in the preferred embodiment of the electrode Steel or nickel alloys. Nickel and silver are according to the invention, in which the active electrogance particularly desirable. Any 5 denier material can be used in an electrically conductive metal die Electrode for silver, zinc and silver, cadmium is retained, the metal matrix acts first or nickel-cadmium cells from these current- as current collectors to bring the current to the output conductor Die metals are produced. So clamps are to be conducted, secondly as structural reinforcement, for example Silver and copper each for themselves by kung to increase the strength of the electrode and great value as a base material for the die of an io third in the sense of increasing the capacity Electrode, for example for the silver electrode or the electrode or the cell in which it is installed for both electrodes in silver, zinc or silver is that the active electrode material is through the Cadmium cells, and the entire mass of the electrode can, for example, be extended through them. Copper or nickel as a die metal for the one in the fabrication of an electrode or for both electrodes of a nickel-cadmium 15 according to the invention one can, for example, in this way before cells use. go that one paste active electrode

As already mentioned above, the pores for the material should be prepared, for example a paste made of zinc

conductive metal of the die must be large enough, and zinc oxide and the pores of the die in this

in order to fill or penetrate a sufficiently large amount of electrode pores that the

shakes the paste back into the die for efficient operation. If necessary

hold, on the other hand, but the pore size can in a preferred embodiment of the

should not be so large that such a small amount of electrode can be used with the finished electrode

conductive die metal receives that the Lei- liftener temperature are sintered. The products

performance of the new electrode construction made of matrix and active electrode material

is reduced or the mechanical strength 25 can then be used in a cell that the

the electrode is seriously endangered. So although electrodes such as a silver electrode and

the pore size of the metal die different a zinc electrode, on opposite sides

Values, the pore diameter should be that of a porous separator attached to a

Metal matrix, for example a nickel matrix, in a silver-zinc high-performance cell for high energy density

Range of for example about 0.203 to 2.54 mm in 30 get.

Be in diameter, and the wall thickness of the In the description that follows, the invention

Honeycomb of the die should be chosen so that manure with reference to the drawing in

for example 8 to 50 such pores on 25.4 mm each are explained. In the drawing is

the length of the die. F i g. 1 a diagrammatic representation of a training

The active electrode material, which in the 35 guide shape of the electrode according to the invention and

Pores of the electrically conductive metal matrix get inside F i g. 2 is a view of a cross section through a

or this fills, is preferably an electrode cell with built-in electrodes according to the invention,

material how to make it into silver-zinc, silver-cadmium How to get from F i g. 1, there is electrode 10

or nickel-cadmium high-performance cells are used, according to the invention from a die 12 made of metal,

and consequently contains electrode material made of 40, for example nickel, which has a considerable porosity

Silver, zinc, cadmium and nickel. Let it be expressed and form more connected

lent mentioned that silver and nickel are used both as honeycomb cells in large numbers with intervening

Metals for the die as well as materials for sensitive pores 14 possesses. The pores 14 are with

can use the active electrode material, with active electrode materials filled or impregnated,

the latter fills the pores of the metal matrix to 45 for example with a paste 16 of silver and silver

In this way, significantly improved electrodes based on oxide or zinc and zinc oxide.

of the invention for high power, high energy cells - A clip or lead 18 which seals to be able to manufacture. can consist of nickel, for example, is

Although the weight percentage of the conductive electrode 10 is attached.

Die made of metal, for example a nickel electrode, as shown for example in FIG. 1 representation matrix, which represents the greater part of the total weight, can make up an electrode in an accumulator cell, that is to say it can be built up to approximately as shown in FIG. 2 shows a section of 80 percent by weight of total active, with metal is. The cell consists of a housing 24 made of synthetic impregnated electrode, contains a preferred fabric and has two symmetrical housing halves 26, electrode according to the invention no more than approximately 55 and 28, which consist for example of Teflon and 10 percent by weight of the metal matrix, for example with the aid of screw bolts 30 held together about 1 to about 10% die metal and may be. The housing halves 26 and 28 of the cell about 90 to about 99% active electrode housing have recesses 32, which are used for the single material in the pores of such a matrix. Electrodes are used which have the functions shown in FIG. 1 electrode constructions, the matrix of which have a smaller 60 drawn shape and, for example, zinc or weight proportion of the total electrode weight can be silver electrodes 10 a and Wb. They make up, for example, only 1 to 10% of their composite zinc electrode 10 a, which is preferably weight, have a considerably greater power - an inorganic thin fiber mat made of potassium in terms of output power per titanate paper 12 a on the inner surface of the electrode weight or volume unit of the accumulator cell 65 is used in the compartment of the housing half compared to electrodes which have a larger size 26. The silver electrode 10b will have the weight portion of its metal matrix because it is used in the opposite housing half 28, and electrodes of the last-mentioned type of the amount active is also a sheet or a mat made of an-

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organic fiber material, for example potassium movements, was introduced into the die, so titanate paper, to the inner surface of the electrode 106 that an embodiment of a zinc electrode according to created. In between there is a separator 38, which was invented.

of either an organic or an inorganic one. A silver paste was then prepared by

Scheider can be. Preferably, an inorganic 5 mixing of silver with silver oxide powder and Scher Scheider in the middle between the housing aqueous potassium hydroxide solution. The pores of the nickel matrix half th 26 and 28 placed so that the electrodes 10 a were with this paste by shaking the paste in and 106 on opposite surfaces of the disc are filled with the die, so that the end result be pressed, whereby the inorganic fiber received a silver electrode. A connecting wire, sheets of paper 12a and -126 between the separator 38 io for example silver wire, was attached to both the zinc and the electrode 10 a and the electrode 106 respectively. electrode and welded to the silver electrode Spacers 40 or are soldered to the circumference of the separator 38.

and 42 made of Teflon inlaid to create a seal. Finally, a thin mat made of potassium

to protect against leakage of liquid. Entitanate paper on top of each made of paste Talking connection lines 18a and 186 are placed on the zinc and silver upper end of the cell, which is made up of a nickel matrix and a zinc or silver matrix, through the electrode parts made of electrode, and the entire electrode assembly plastic passed through. Small storage container 48 voltage was placed in a cell as shown in FIG. 2 of the drawing and 49 for the electrolyte are inserted in the upper part of the, so that the potassium titanate paper sheet corresponding housing halves 26 and 28 are provided. between the corresponding electrodes and the Of course, if necessary, the mats could be 20 separators. Eventually the cell was put together-12 a and 126 built away from inorganic fiber material, with 25 to 30% KOH as electrolyte and can be left, or just one of the electrodes can be an inorganic separator made of sintered ceramitrode in the embodiment according to FIG. 2, for example, aluminum silicate was used, wise the zinc electrode 10 a in connection with the After charging this cell with a specific

Potassium titanate paper 12a can be used so that 25 amperage of 50 milliamps per square centimeter the potassium titanate paper 126 on the silver electrode (mA / cm ² ) can be omitted for a total capacity of 2.75 Am-106. per hour (Ah) the cell was with 50 mA / cm ²

More examples of other suitable fibrous discharges. The capacity of the cell was the first inorganic substances required for parts 12a and 126 to discharge 1.675 Ah, which is about three times In addition to the titanates, 30 are as large as the capacity of common standard silver, for example Potassium titanate, aluminum silicates, silicon zinc cells of this type using conventional ones zium, zircon and alumina. Zinc and silver electrodes, d. H. so without the metal

When assembling high-performance cells with matrices, as is the case with the electrodes according to the invention. 2 of the drawing, the application will be used. The conventional electrodes, preferably together with inorganic cells without metal, for example nickel matrices, separators in the form of insoluble aqueous metal oxides, have a capacity on the first discharge which is generally approximately 0.50 to 0.60 Ah, for example in the form of aqueous zirconium oxide. It has also been found, or in the form of sintered ceramic parts, for example, that the level is used for the detection of sintered aluminum silicate. Charging voltage in the cell according to the invention, such as organic separators, which you can use in the manufacture 4 ° it was mentioned above for example and in which of accumulator cells with electrodes according to the silver and zinc electrodes in connection with an invention, contain, for example, nickel matrices for use Microporous plastics such as nylon, Dynel, Teflon are larger than in comparable cells that do not use a nickel matrix or artificial casing made of matted regenerated in the electrodes. With this embodiment cellulose and the like, however, other types of inorganic or organic separators according to the invention, the discharge voltage can also be used if necessary. As mentioned above, the separator has the same cells with silver and zinc electrodes, but the task of holding back the electrolyte is around 1.35 volts without the nickel matrix. Separating electrodes from one another, but at the same time 50. After recharging, the cell was also given the task of allowing the passage of electrolyte ions - in this example with the electrodes according to the invention - but discharging ^{the passage of electrons at a current of 80 mA / cm 2} , taking to prevent denions. The following are some examples of the Her current strength 1.6 Ah.

position of electrodes according to the invention and their 55 comparable cells without metal matrix in the Installation in accumulator cells are given. Electrodes have a much lower capacity (0.6 to

0.9 Ah) at this discharge current strength or example 1 cannot even deliver such high discharge currents.

The cell of this embodiment was then

Silver and zinc electrodes were repeated using 60 at 100 ° C and 22.5 mA / cm ² charging and charging each of a porous nickel matrix with a pore 17.5 mA / cm ² discharge current during half a diameter of about 0, Discharged 76 mm and approximately 25 pores hour and charged during half an hour for every 25.4 mm of linear expansion of the die, and a total of 600 cycles were produced. A zinc paste was passed through by mixing. The efficiency of the cell and that of zinc, zinc oxide and about 1% polyvinyl alcohol were completely flawless. An examination of the electrodes in the form of a sludge together with 30 ° / ₀ KOH after such a process. This paste was shown in the pores of the nickel search rows that the electrodes were filled in a die, the paste being in a condition that was excellent for shaking.

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Example 2 Example 4

A silver electrode was prepared using a There was a nickel and cadmium electrode nickel matrix as in the Example 1 and prepared and in both cases, a porous Kupferder entire electrode structure then at 300 ⁰ C overall 5 die used with a pore diameter of sinters. This electrode was made with a conventional zinc electrode of about 1.270 mm and about 18 pores per 25.4 mm with paste without a nickel matrix of its linear extension. Nickel hydroxide was assembled. This cell, too, was first built from a nickel-nitrate solution with the help of men, as shown in FIG. 2 and precipitated with ammonium hydroxide. The nickel hydroxide charged 20.0 mA / cm ^2. This resulted in a deposit of 2.1 Ah in the first discharge process to remove the ammonium nitrate, compared to 0.5 to 0.6 Ah with a conventional wash then at 95 ° C for 24 hours in the oven dry- or regular cell with a paste and silver and net. A paste was then produced which contained 80% zinc electrodes, none of which had a nickel matrix of this nickel hydroxide and 20% graphite powder, and compared to 1.675 Ah for the cell after 15, it contained 30% KOH as a carrier. Then an example 1. Copper matrix of the type described above was filled with the nickel paste mentioned above. A comparison of Example 1 with Example 2 shows that the cell according to Example 2 was shaken into the pores of the matrix with a silver paste that was sintered into a nickel die. Then a paste of cadmium has become much more effective than the cell according to 20 oxide using 30% KOH as the carrier Example 1, in which both silver and zinc are prepared. A copper matrix, as described above, has been placed in a nickel matrix with the pastel electrodes, was filled with the cadmium paste by sintering, but neither of the two electrodes shaking the paste into the pores of the matrix,
has been. Here, too, a cell similar to the one in

25 Fig. 2 cell shown assembled under

Example 3 Turning the copper matrix filled with paste and

the nickel and cadmium electrodes using

In this example, silver and zinc electrodes were made from about 30% KOH as the electrolyte and an electrode, and in both cases an inorganic separator made from a sintered, ceramic silver matrix was used. A silver aluminum silicate was then applied. The cell produced in this way showed paste made from a mixture of 50% silver and 50% a significantly higher capacity when discharging silver oxide and 30% KOH as a carrier. Those with a high specific current, compared to the pores of each silver matrix, had a diameter of a conventional nickel-cadmium cell of about 2.03 mm and about 10 pores per surface type, but using a conventional 25.4 mm linear expansion of the matrix ; these pores 35 nickel and cadmium electrodes, and without one, were made with the paste by vibrating it in a metal die according to the teachings of the invention,
the die is filled. It then became a zinc paste by making a 92% mixture of Example 5
Zinc oxide and 8% mercury oxide in 30% potassium hydroxide solution. If nickel and cadmium electrodes are sintered, they are used as carriers. The pores of a similar 40 of the paste and with the copper die after the Erfin silver die, as described above, were filled with manure prior to assembly in a cell at about this paste. 350 ^° C., then an even higher capacity results. as shown in FIG. 2 of the drawing is shown, 45 built in with pastes and copper matrices for use, and it got 25 to 40% KOH as reached.

Electrolyte and an inorganic separator from water τ,. · Ι α

according to zirconium oxide for use. ^{e l} ^ ^{l e}

A cell assembled in this way has an increased first set of silver and

Capacity made at both ambient temperature and 50 zinc electrodes; one got here

at higher temperatures in the order of 18-8 (18% nickel and 8% chromium) die made of rust

100 ° C and more compared with the same cell free steel by the method of Example 1 for

with conventional silver and zinc electrodes.

without a metal die according to the invention. So thereupon was a second set of silver and

is the capacity of a cell at 25 ° C with 55 zinc electrodes, whereupon a Cromel

Troden with a silver matrix 2.45 Ah, while the Kapa matrix (a nickel-chromium alloy) after the

The same cell was manufactured using conventional silver and method according to claim 1.

Zinc electrodes under the same conditions Both sets of silver and zinc electrodes were made

1.5 Ah. then placed in a cell as in the case of example 1

The zinc and silver electrodes are sintered together.

Men with the silver matrix, for example at 500 ° C, each of the cells produced in this way has a high

and then the paste of silver and zinc is applied, which is greater than the capacity of the

into the silver matrix, then shows a cell with the same cell as the conventional silver and

such a way sintered electrodes with a total zinc electrode, but without the matrices according to the

structure as shown in FIG. 2 is an even higher 65 invention made from stainless steel or from a

Capacity compared to a cell with unsintered nickel-chromium alloy.

Zinc and silver electrodes, but with a silver matrix, as can be seen from the above examples with everything

it has been described above. Clarity that the use of a die made

an electrically conductive metal according to the invention, which is impregnated with an active electrode material and in a high capacity cell using silver and zinc, silver and cadmium or Nickel and cadmium are incorporated, leading to increased capacity, higher levels of discharge voltage and a better capacity during discharge, especially with a high specific discharge current, these advantages being achieved both at room temperature and at higher temperatures, and Nevertheless, a long service life can be recorded with a large number of cycles. Sintered electrodes offer additional advantages in this regard.

During the discharge of a cell of the type described above and shown in the drawing For example, the zinc is converted into zinc oxide and the silver oxide is converted in a manner known per se Silver reduced. During the charging of such cells, the silver is oxidized to silver oxide and that Zinc oxide reduced to zinc. Because of these reversible chemical reactions, the designations "Silver" and "zinc" as well as the terms "silver" and "cadmium", but also the terms "nickel" and "cadmium" and the term "metal" insofar as they refer to the metals which the corresponding Form electrodes of such cell systems, either the corresponding metals themselves or their mark the corresponding oxides.

Claims (3)

Patent claims: 1. Electrode for accumulator cells with a porous matrix made of electrically conductive material in Form of interconnected honeycomb cells, the pores of which are large enough to accommodate them with a to impregnate active electrode paste, characterized in that the diameter the pores (14) is in the range between 0.23 to 2.54 mm, about 8 to 50 pores (14) per 25.4 mm the length of the die (12) and that the proportion by weight of the die (12) made of metal 1 to 10 percent by weight of the total weight of the electrode (10). 2. Electrode according to claim 1, characterized in that the porous electrically conductive metal for the die (12) is selected from the group consisting of nickel, copper, silver, stainless steel or Contains nickel alloys. 3. Electrode according to one of claims 1 and 2, characterized in that the electrode is sintered is. 1 sheet of drawings