DE1927093A1 - Air-breathing electrode - Google Patents

Description

Applicant: ESB Incorporated

Air-breathing electrode

The present invention relates to an air-oxygen-breathing electrode and an air-oxygen cell or an air-oxygen element which contains a metal anode and an air-oxygen-breathing electrode which contains a microporous I ¹ IIm made of an IPluocarbon polymer applied to one side that is directly exposed to the atmosphere and The air oxygen electrode enables the liquid electrolyte to be confined to the inside of the cell and at the same time to "breathe" the oxygen in the air from the atmosphere by allowing the air (oxygen) from the environment to flow through the air electrode and the area of the electrolyte air electrode -Lets reach the boundary. Recharging can be achieved using a charging electrode or by simply replacing the metal anode.

A conventional fuel element has two metal electrodes, often made of the same material, immersed in an electrolyte, with everything placed in a container. Expensive catalyst materials are used for fuel metal electrodes , and carefully worked out installations are required for the supply of fuels, oxygen and hydrogen, ^ _2-

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to the respective electrodes and to remove the by-product water. Such cells or elements have good ones LeMing parameters. The mechanical difficulties Occur in connection with maintenance, but make it appear desirable to develop an element or a cell, which utilizes the fuel element technology in an advantageous manner, but at the same time the mechanical problems eliminated, inherent in the use of fuel elements. Research in the field of various energy sources led to the development of atmospheric oxygen elements, which have an oxygen electrode that is used to "breathe" Air is capable while under a variety of conditions including its standard atmospheric environment is working.

The conventional atmospheric oxygen cell, also called a metal-air cell is described, consists of a container that holds at least one negative electrode, e.g. zinc, and one contains porous air electrode. The electrolyte is usually an aqueous solution of sodium hydroxide. This kind of Cells are called "air depolarized", since air passes through the porous electrode from the atmosphere, which leads to a three-phase interface between the electrode surface-air-electrolyte in the district where oxygen in the air acts as a depolarizing agent. The porous air electrode is immersed in the electrolyte that is in flows into the pores and penetrates the electrode. Complete saturation of the air electrode by the electrolyte however, it leads to the element not working because of the clogging of the electrode pores by the electrolyte prevents the oxygen from reaching the electrode surface. This stops the depolarization.

Matching a fuel element oxygen electrode to a metal-air cell would be the requirement of the needed Equipment for supplying oxygen to the electrode ele-

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mine. If the oxygen electrodes are enabled to do so could "breathe" the oxygen from the atmosphere while confining the electrolyte to the cell, there would be an unrestricted flow of oxygen to reach a maximum area of the electrode surface. One would then obtain the type of a metal-air cell in which the air electrode is also a container wall could. Such an electrode is disclosed by the present invention.

The present invention relates to a metal-air cell in which a new air electrode is used which is liquid-tight and contains an applied film of a microporous fluorocarbon polymer on one surface. These The new electrode serves both as an electrode and as a container wall.

The present invention accordingly relates to an electrode which breathes in air and is characterized by a metallic lattice part, a catalyst mass applied to the lattice part, and a thin microporous film material made of a fluorocarbon polymer, which is applied to one side of the atmospheric oxygen electrode.

Essentially, the method of making the microporous air electrode is to make a porous wetting-resistant one Pressing the catalyst mass onto a metallic grid part and then onto one side of this base body to apply a microporous film material made of a fluorocarbon polymer, which is capable of To make the electrode liquid-tight. The microporous film material made from a fluorocarbon polymer was used Polytetrafluoroethylene used. The present invention thus makes it possible to develop a metal-air cell which has an air electrode which confines the electrolyte into the cell and is capable of drawing air from the atmosphere to flow through the electrode to __,

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inner electrode surface, due to the film of ' a microporous fluorocarbon polymer mass which is applied to the outer surface of the air electrode. An air electrode with these properties can be said to "breath" air or oxygen.

Another approach according to the invention is a metal-air cell in which a film made of polytetrafluoroethylene is applied to the surface of the air electrode, which surface is directly exposed to the atmosphere, and wherein the pores of the film made of polytetrafluoroethylene have such a size that they enable the Lufteleictrode to air "breathe" while impervious to the electrolyte.

The present invention also includes a metal-air cell with two negative electrodes and two air electrodes, each air electrode serving as the container wall of the cell and a coating of a fluorocarbon polymer film Contains on the electrode surface that is exposed to the atmosphere is. The layer made of the microporous fluorocarbon polymer enables the air electrodes to do this at the same time to serve as air electrodes and as container walls. According to the invention, microporous polytetrafluoroethylene is used as the film applied to the outer surfaces of the air electrodes. The present invention includes also a metal-air cell, which is an oxygen-breathing cell Contains an electrode with a microporous fluorocarbon polymer film on one side and a negative electrode, whereby the cell can be easily recharged by means of a charging electrode or by removing the negative electrode and replacing it with a new electrode.

The present invention also includes a metal-air cell in which the air electrode has a surface which is directly exposed to the external environment and which surface is provided with a fluorocarbon polymer film which enables the air electrode to perform its function _c

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to be filled in an atmosphere partially containing oxygen.

To better understand the practice and features of the present invention and the results achieved therewith reference is made to the accompanying drawings.

Figure 1 is an illustration of the cell without the metal charging electrode. It explains the construction of a primary element with electrodes breathing oxygen and only one negative electrode.

Figure 2 is an illustration of the cell with the metal charging electrode. It can be seen as an explanation of the construction of a secondary element, the two air-oxygen breathing elements Contains electrodes.

FIG. 3 is a side view of a metal-air cell of FIG Fig «1 shown type, but fully assembled and ready for use. It shows the cell frames in section and the rest of the cell in elevation. In the individual figures, the individual reference numbers denote the same in each case Parts.

FIG. 4 illustrates a support frame for the inner elements of the cells shown in FIGS.

The figures each show a single cell with two air electrodes, which can be viewed as positive electrodes. However, the cells do not have the same number of negatives

electrodes. However, it is expressly pointed out that the special cell constructions shown here are not be viewed as a limitation of the scope of protection oll. In Fig. 2 a cell according to the invention is shown, a metal charging electrode between the two negative electrodes contains. An element can also be operated without a charging electrode. In this case a cell,

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as shown in Fig. 1 and with only one negative • Electrode is used. Of course you can the charging electrode can also simply be removed between the two negative electrodes in the cell shown in Mg. 2.

In Figure 1, a metal-air cell 20 is shown, wherein the individual components have been pulled apart for clarity. Plastic end frames 2 serve as a structural Scaffolding for the cell. The cell is firmly compressed between these end frames, the air electrodes 3 as External walls serve. A fluorocarbon polymer film 11 is applied to the outer surface of the air electrode and exposed to the atmosphere, while the moisture-proof Surface 17 of the air electrode is in contact with the electrolyte. The metallic grid part of the air electrode is denoted by 24.

These air electrodes contain a metallic grid onto which a porous catalytic mass is hot-pressed. That Grid metal is preferably expanded metal or screen-like in order to ensure good adhesion of the catalytic mass to the grid. The catalytic mass consists of a moisture-resistant Agent mixed with an electrically conductive carrier material in particle form, one being electrochemically active catalyst is deposited on the particles. A moisture-proof mass could also can be produced without an electrochemically active catalyst. The electrochemical reaction rate im The area of the air electrode would then necessarily be reduced. Therefore it is preferably a catalyst to be used in the manufacture of the air electrode.

The spacers 4 can be made of plastic.

and serve as spacers between the air electrodes and the negative electrode 5, which are also made of a separating material 6 is wrapped. The separating material can consist of an opposite

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the electrolyte-resistant, highly absorbent matt fiber, such as those commercially available, for example is available under the trade name "Webril". These spacers are not essential to the invention. But they fulfill the very useful function that they are a result in greater electrolyte volume than would be present without these spacers. A larger volume of electrolyte is desirable in view of the tendency of the water from the electrolyte through the pores of the air electrodes into the To evaporate the atmosphere outside the cell. The stripes 7 the air electrodes are connected to one another in parallel to the outer connection terminal of the air electrodes. The strip 8 is used as a terminal for the negative electrodes. If a charging electrode is not present, as in Figure 1, a single negative electrode can be used in place of the two electrodes 16 shown in FIG. The spacers 4 and the negative electrode 5 can be held in the correct position by means of a frame between the air electrodes is arranged »Such a frame 25 is not absolutely necessary for the purposes of the invention. He jsfc however a convenient aid in assembling the cell according to the invention and is shown in FIG.

In Figure 2, a metal-air cell 21 is shown with a charging electrode 14, which is between the two negative electrodes 16 is inserted. The charging electrode is also surrounded by a separator material, for example made of cellophane. the Strips 7 connect the air electrodes parallel to the external terminal, while the leads 9 have the same function for the negative electrodes to exercise. The charging electrode is connected by the strip 14 to the external terminal.

During the operation of a cell, as shown in Figure 2, air passes directly from the atmosphere through the Micropores of the fluorocarbon polymer film in the air electrodes 3 and acts as a depolarizing agent on the Boundary between the electrolyte and the surface of the

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Air electrode. By the size of the micropores of the fluorocarbon polymer film 11, in this case made of polytetrafluoroethylene, which is applied to the outer surfaces of the air electrodes is applied, the air electrodes are able to be impermeable to the electrolyte during a Allow air to pass freely through the electrodes.

The separator material 13 surrounding the negative electrodes serves to keep these electrodes separated from the air electrodes, which helps a short circuit to prevent between the electrodes. The charging electrode can also be enclosed in a separator material, which is based on the effectiveness of the cell performance has no influence, but also a contact between the charging electrode and the negative ones Electrodes by preventing the dendrite growth that can occur during cell charging. After the discharge, the negative electrodes can be charged again using the charging electrode. if the Construction of a primary element according to FIG. 1 is used, the discharged negative electrode can be used for recharging can simply be replaced with a new one. The spacers 4, the negative electrodes 16 and the charging electrode 14 can all be held in place between the air electrodes by a frame similar to that shown in FIG is described above and shown in FIG.

FIG. 3 shows a side view of an assembled cell 20 according to FIG. 1, partly in section and partly shown in elevation. Such a view of a cell according to the invention is to some extent misleading as it does Can give the impression that the cell is thick and that there is a greater distance between the air electrodes than it actually is given is. It should therefore be noted here that a composite cell according to the invention is very narrow, when seen from the side. It was shown in FIG only partially shown in a broader way for the sake of clarity. Q

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In FIG. 3, the plastic ribbon frames 2 hold air electrodes 3 of the type disclosed according to the invention firmly pressed together with the spacers 4, between which a negative electrode 5 is encased by a separator material 6 arranged. The air electrodes are parallel and facing the outer Terminal connected by strip 7. The strip 8 serves as the external lead for the negative electrode. the Elements 4, 5 and 6 are shown within a frame 25 of the type shown in FIG. The electrolyte 26 fills the interior of the cell between the air electrodes 3.

An important feature of the present invention is the construction of the air electrodes 3. While the inner surface 17 and the outer fluorocarbon polymer surface 11 of an air electrode according to the invention in the figures 1 and 2, reference is now made to FIG. 1 to illustrate the construction of the air electrode and to explain its nine characteristics.

The basic structure of an air electrode according to the invention has already been explained above. In particular, the air electrode, with reference to FIG. 1, consists of three basic elements: namely a metallic grid part 24, a moisture-resistant catalytic mass which is pressed onto the mentioned grid part and is shown as the inner surface 17 of the air electrode, and a surface layer or a Film made of a fluorocarbon polymer 11 which is applied to one side of the grid.

The metallic grid member 24 has the function of a current collector and a supporting grid and is preferably a Expanded metal or a sieve, as the ribbed structure is the Adhesion of the catalytic mass to the grid is increased to form a grid. In addition, the metal used for the grid part must have good corrosion resistance in the electro-

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possess lytmedium of the cell. With alkaline electrolyte solutions It is generally preferred to use nickel meshes, although silver and silver plated copper meshes are also preferred have been used successfully. In an acidic electrolyte, mob, tantalum, titanium, molybdenum can be used as the grid material and zircon can be used.

The catalytic mass present on the inner surface 17 of the air electrode generally consists of one electrically conductive carrier material in particle form, which is used as a carrier for an electrochemically active Catalyst is used. Carbon is the generally preferred support material in view of the low Price, although other carrier materials such as boron nitride or finely divided metal powder can also be used. Of the electrochemically active catalyst which is applied to the support material can be one of the generally known fuel element catalysts be like silver, gold and the metals of the platinum group (ruthenium, rhodium, osmium, iridium, Palladium and platinum). It should be noted that carbon material is in particulate form with such deposited thereon Catalysts is commercially available. It is also possible to use finely divided catalyst materials without a carrier. However, since the catalysts are generally very expensive, it is preferably a cheaper support material such as carbon to use. In addition, finely divided carbon can be used as a catalyst material without any of the above-mentioned expensive ones Catalysts are used. However, these catalysts significantly improve the efficiency of the electrochemical reaction, which takes place at the air electrode. Therefore, it is preferred that one or more of these catalysts in the catalyst mass are present.

In addition, the catalyst mass can contain a hydrophobic material which serves as a moisture-resistant agent. The purpose of such a moisture-proof agent is to prevent the electrolyte from completely exhausting the air.

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electrode impregnated when it is in contact with the aqueous electrolyte. It is in the field of Brennstof £ elements known Fluorkohlenstoffpolymerisate such as polytetrafluoroethylene, Polytrifluoräthylen, polyvinyl fluoride, polytrifluorochloroethylene and Goplymerisate thereof as moisture resistant "means Gaseleirtroden to use, and they have been found to be satisfactory for the oxygen in the air breathing electrodes according to the invention. Silicone resins or Paraffin wax can also be used as a moisture proof agent.

In general, the catalyst material is present in amounts in the range between about 0.01 and about 10% by weight of the support material, with about 5 ° platinum having proven to be very advantageous. The moisture-resistant fluorocarbon polymer agent is generally present in a proportion of about 5 to about 60% by weight, based on the total catalyst mass, with about 20 % being preferred.

The thin, microporous fluorocarbon polymer material in film form, which is applied to one surface of the air electrode, is an essential feature according to the invention. This fluorocarbon polymer film material must have a uniform microporosity that the electrode enables you to breathe air. The micropores must be of such a small size that the hydrophobic property of the fluorocarbon polymer inhibits the electrolyte therein by the fluorocarbon polymer sheet material to seep through. It has been found that the pore forming particles should be small enough to pass through a 200 mesh screen to happen. This corresponds to a particle size of about 73 microns or less. Particles passing through a 325 mesh sieve happen, corresponding to a particle size of about 40 microns or less, have an excellent microporous polytetrafluoroethylene result. Furthermore, it is necessary that the fluorine-carbon polymer film material is firmly attached to the catalyst mass adheres to prevent the film from falling off the

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Electrode peeled off when the air-metal cell in which the air electrode is used is subjected to the charge-discharge cycle will. In general, the fluorocarbon polymer sheet material can be made from the same fluorocarbon polymers which are used as moisture proof agents. Polytetrafluoroethylene is particularly preferred. The manufacture of the microporous fluorocarbon polymer sheet material is described in detail in Example 1 and in a patent application entitled "A Method for Making Thin, Microporous Fluorocarbon Polymer Sheet Material, "submitted by Jack C. Sklarchuk and William F. Kobie and assigned to the assignee of the present patent application. It has been found that generally fluorocarbon polymer sheet material having a thickness ranging from about 5 to about 30 mils is satisfactory.

In the case of an acidic electrolyte, lead is suitable as the metal for the negative electrode, while niobium, tantalum, titanium, zirconium or molybdenum can be used for the charging electrode, if one is present in the cell. Antimony itann can also be used for the negative electrode in an acidic electrolyte. However, it is not so desirable like lead, due to the lower discharge voltage. In the case of an alkaline electrolyte, the negative electrode made of zinc, cadmium or iron, while the charging electrode, if one is used, made of a Material can be made that is corrosion resistant in the alkaline solution, for example nickel. Magnesium is a suitable material for the negative electrode in a salt water electrolyte. Also, graphite can be used as a material can be used for the charging electrode in any electrolyte.

The manufacture of the air electrode requires care to ensure uniform microporosity the fluorocarbon film deposited on a surface of the electrode is applied. The following example provides a detailed description of the process for producing

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position of an air electrode containing the new properties of the air electrode according to the present invention.

example 1

Oalciumformat (CaCCHOg ^) was dried at 12O ⁰ C and sieved through a -325 mesh sieve. A 5/1 mixture was prepared by mixing 250 g of Ca (CHOp) ρ powder with 83.3 g of a polytetrafluoroethylene emulsion (Teflon 30) containing 50 g of polytetrafluoroethylene polymer. The emulsion was diluted with 50 ml of water, stirred vigorously, and then the Ca (CHOp) p powder was slowly added. Shallow thorough mixing of this mixture for 10 minutes, it was ^{dried to complete dryness at 125 °} C. and then ground to microparticles in a high-speed mixer. 15 g of paraffin wax were thoroughly mixed into this mass before it was formed into sheet material.

A rubber mill was used to form sheets from the mixture produced. The back roller of the mill was heated to 60 ⁰ C and the front roller 71 ⁰ C. The gap between the rollers was adjusted so that a film 20 mils thick was obtained. The pulverized semicircle was poured onto the rubber roller, rolled once, pulled off the grinding roller, turned over and rolled again. This roll-stripe-roll procedure was repeated to ensure correct strength and uniformity. The material was then stripped from the rollers and obtained as film material. The films were allowed to cool and became stiff, but durable and easy to work with.

The rolled foils were then put into a Soxhlet extractor which contained warm acetone (just below boiling point) to remove the paraffin wax. This Extraction process took about half an hour. The excess acetone on the film material was extinguished and the foil was placed in a cold sinter

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oven given. The furnace was slowly ^{heated to 345 °} C. and the polytetrafluoroethylene was sintered ^{at 345 ° C. for about half an hour.} The film was then allowed to cool to room temperature.

A catalyst composition was prepared by an aqueous slurry of a precipitated on a carbon support 5 i> platinum catalyst which is commercially available was of Englehardphergestellt. This slurry was stirred rapidly and a dilute solution of a polytetrafluoroethylene emulsion (Teflon 30) was slowly added to the slurry in such an amount that it contained 20% by weight of polytetrafluoroethylene based on the total weight of the dry catalyst mass. After the olytetrafluoroethylene was mixed into the catalyst mass to form a homogeneous mixture, the mass was washed thoroughly in water, then in acetone and then again in water. Three g of this moisture-resistant catalyst mass were pressed onto a clean 75 mesh nickel screen at a pressure of 1000 kg / cm at room temperature. An air electrode was obtained which had an area of 6.35 cm × 6.35 cm on each side.

A piece of the sintered was placed on one side of this air electrode Polytetrafluoroethylene Iolienmaterials, which still contained the Galciumformat as a pore former, in one Pressure of 1000 kg / cm and at a temperature of 205 ° C for 2 minutes. After the polytetrafluoroethylene film was pressed hot on the air electrode, the electrode containing the foil was in warm water (99 ° 0) immersed to remove the calcium format pore former. To ensure complete removal of the pore former, the electrode was left in the warm water for about 16 hours (over fold). Then it became from the Taken out water and allowed to dry.

This electrode was used as a half-cell in a 27 $ potassium hydroxide electrolyte tested, taking under different

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the following stresses have been obtained:

Volt against H ₂

Open circuit voltage 20 mA / cm 50 mA / cm 100 mA / cm ² 150 mA / cm ² 0.980 0.650 0.770 0.645 0.455

In the following examples are some working characteristics reproduced by metal-air cells of the type shown in Figure 2, which have 2 air electrodes and 2 negative electrodes, different metals were used for the negative electrodes. The air electrodes were from the example 1 type described, wherein polytetrafluoroethylene was used as a microporous fluorocarbon polymer film. The thickness was in the range between 5 and 50 mm. The foil was applied to the electrode surfaces, that of the atmosphere are exposed.

Example 2

In the cell used in this example, air elecs were: - electrodes of the type described in Example 1 were used against magnesium electrodes, and the electrolyte consisted of seawater. The cell operated in an air environment at normal pressure and room temperature. The cell potential was in Volts measured as a function of current density in milliamps per square centimeter.

Cell potential (volts) Current density (mA / cm) 1.5 0 ok 10 1.22 20th 1.19 30th 1.13 40 1.-0 50 0.5 60

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Example 3

In the cell used in this example, the air electrodes were The type described in Example 1 was allowed to work against cadmium electrodes, the electrolyte being 27% Potassium hydroxide solution was. The cell would operate at a constant current density of 25 milliamps per square centimeter calmly. The readings of the cell potential in volts were given over a period of time as a function of the number the charge-discharge cycles of the cell are taken. The cell was allowed to work in an air environment free of carbon dioxide at room temperature.

Time (min.) 0 10 20 30 40 50 60 cells-cells-cells-cells-cells-cells-cell-potential poten- poten- poten- poten- poten-

Cycles tial tial tial tial tial tial

1 0.78 0.775 0.77 0.75 0.725 0.68 0.60

50 0.68 0.66 0.63 0.60 0.55 0.48 0.58

100 0.60 0.57 0.53 0.47 0.39 0.29 0.05

150 0.50 0.48 0.45 0.42 0.36 0.29 0.15

200 0.48 0.445 0.40 0.35 0.26 0.13 0

250 0.48 0.445- 0.41 0.36 0.27 0.17 0

Example 4

In the cell of this example, the air electrodes of the type described in Example 1 were made to work against zinc electrodes in a 21% potassium hydroxide electrolyte. The data were obtained when the cell was operated at room temperature. In one series of experiments, the current density was measured as a function of the cell potential, while in another series of experiments the cell potential was measured at a constant current density of 25 milliamps per square centimeter as a function of the number of charge-discharge cycles. The environment was again air from which the carbon dioxide had been removed.

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Current density (mA / cm) Cell potential (volts)

0 1.50 10 1.34 20th 1.27 40 1.19 50 1.14 70 1.06 100 0.95 120 0.88 150 0.77 170 0.73 200 0.64 250 0.48

Time (min.) 0 10 20 30 40 50 60 Number of cells-cells-cells-cells-cells-cells-cells Potential potential potential potential potential tial tial tial tial tial

1 1.24 1.18 11 1.21 1.16 21st 1.18 1.15 31 1.16 1.10 40 1.15 1.10 77 1.13 1.03

1.16 1.16 1.16 1.16 1.12 1.12 1.10 1.07 1.09 1.06 1.01 0.95 1.03 0.96 0.84 0.60 1.04 0.99 0.93 0.82 0.93 0.86 0.76 0.50

1.17 1.13 1.10 1.07

1.07 0.98

From the data presented in the examples above, it is
It can be seen that a metal-air cell made in accordance with the present invention has good performance characteristics
as a source of electrical energy, in addition to having new mechanical and chemical properties. The ability to be subjected to a charge-discharge cycle many times is particular
an important feature of the present invention.

Patent claims:

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Claims (18)

19270S3 claims 1. Air-oxygen breathing electrode, marked through a metallic grid part, one on the grid part applied catalyst mass, and a thin, microporous film material made of a fluorocarbon polymer, which is applied to one side of the atmospheric oxygen electrode. 2. Electrode according to claim 1, characterized in that essentially all of the micropores of the fluorocarbon polymer film material formed from pore-forming particles having a particle size no greater than about 73 microns are. 3 · Electrode according to claims 1-2, characterized in that the fluorocarbon polymer is polytetrafluoroethylene. 4. Electrode according to claims 1-3, characterized in that the catalyst mass consists of an electrochemically active Catalyst on electrically conductive carrier particles is precipitated, and is made of a hydrophobic moisture-proof agent. 5. Electrode according to claims 1-4, characterized in that the carrier material is carbon and the catalyst consists of gold, silver, platinum, palladium, rhodium, osmium, iridium and / or ruthenium. 6. Electrode according to claims 1-5, characterized in that essentially all of the micropores of the fluorocarbon polymer film material formed by pore-forming particles having a particle size no greater than about 40 microns are. 7 · Air oxygen cell with one immersed in an electrolyte negative electrode and an air electrode, characterized in that the inner porous surface of the 00 9886/0796 - 19 - 19270S3 The air electrode is in contact with the electrolyte the outer surface of the air electrode contains a microporous fluorocarbon polymer film applied and is directly exposed to the external environment, with the microporous fluorocarbon polymer film being the air electrode it enables the electrolyte to get inside the cell while at the same time allowing a free passage a gas from the environment into the air electrode to the area of the interface between the inner surface of the Air electrode and the electrolyte is made possible. 8. Air oxygen cell according to claim 7 »characterized in that that the negative electrode is separated from an air electrode by means of a separating device, the air electrode has an inner porous surface in contact with the electrolyte and an outer surface on which a polytetrafluoroethylene mass is applied and which is directly exposed to the surrounding atmosphere, the Polytetrafluoroethylene has micropores of such a size that the air electrode is capable of the electrolyte keep inside the metal air toe while at the same time a free flow of one containing oxygen Gas flow from the surrounding atmosphere into the air electrode to the area of the interface z'tfisehen the inner surface of the air electrode and the electrolyte is made possible. 9 · Air oxygen cell according to claim 7, characterized in that that the inner surface of the air electrode is in contact with the electrolyte, the outer surface of the air electrode the outside surface of the air electrode is a microporous fluorocarbon polymer film contains applied, which enables the air electrode to bring the electrolyte into the interior of the cell, while at the same time allowing free passage of air from the environment into the air electrode and in contact with the electrolyte, and further characterized by a charging electrode, the 009886/0796 between the negative electrode and the air electrode is arranged. 10. Air oxygen cell according to claim 7, characterized in that that the cell has two negative electrodes immersed in an electrolyte, two air electrodes, one charging electrode between the anodes, for the sake of space between the Anodes and the charging electrode, and separators contains between the negative electrodes and the air electrodes, the air electrodes having an inner moisture-proof Surface in contact with the electrolyte and have an outer surface on which a layer is applied from a fluorocarbon polymer mass, which makes every air electrode impermeable to the electrolyte and a free passage of an acid, st off / carrying gas flow from the atmosphere into the air electrode to the interface between the electrolyte and the inner surface of the air electrode. 11. Air oxygen cell according to claims 7-10, characterized in that that the! fluorocarbon polymer mass Is polytetrafluoroethylene. 12. Air oxygen cell according to claim 7, characterized in that that it contains an air electrode which has a film of a fluorocarbon polymer mass on the outer Contains surface that is directly exposed to the atmosphere, the fluorocarbon polymer film being micro-oores of such a size that the air electrode mn- lind permeable for the electrolyte is yin the hunt as I.ii.i'telectrcde in a gaseous oxygen containing To act atmosphere, so that the oxygen from the .Atmosphäre flows into the air electrode and the interface reached, the sswischen the electrolyte, the air oxygen cell and the inner surface of the air electrode is present. - 21 - 0 ^ 9886/0796 13. Air oxygen cell according to claims 7-12, characterized in that the electrolyte is an alkaline solution ^ tide the negative electrode is made of zinc, cadmium or iron 14 · Air oxygen cell according to claims 7-12, characterized in that the electrolyte is an acid and the negative electrode consists of lead or antimony. 15 · Air electrode according to claims 7-12, characterized in that the electrolyte is sea water and the negative Electrode is made of magnesium. 16. Air oxygen cell according to claims 7-13, characterized in that the electrolyte is an alkaline solution and the charging electrode is made of nickel 17 · Air oxygen ropes according to claims 7-12 and / or 14, characterized in that the electrolyte is an acid and the charging electrode consists of HiOb ₉ tantalum, zirconium, sitane or molybdenum. 18. Luftsaueretoffzell according to claims 7-12 and / or 14, characterized in that the electrolyte is an acid and the metal grid of the air electrode made of niobium, tantalum, Zirconium, titanium or molybdenum. ι. Air oxygen cell according to claims 7-13 »characterized in that the electrolyte is an alkaline solution and the metal mesh of the air electrode is made of nickel or silver. BATH ORIGINAL 009886/0796 Lee r side