Galvanic element

Description

0. D. 621.352.5 Copyright reserved. PATENT COUNCIL PATENT No. Issued July 16, 1956. Date June 16, 1956. THE NETHERLANDS LP.C. H 01 m. CLASS 21 b 13 b (21 b 6). COMPANY KASIMIR BAÜMGARTEN, in Wildstein b. Eger, Cheeho-Slovakia e. Galvanic element. Application No. 112627 Ned., submitted 13 August 1943, 15 hours; made public 15 February 1956, priority from 18 August 1942, (Germany). For the manufacture of atmospheric oxygen elements, i.e. galvanic elements, the positive electrode of which contains essentially activated carbon as the active substance, which causes depolarization by the oxygen of the air, a concentrated ammonium chloride solution with the addition of zinc chloride is generally used as the electrolyte, insofar as dry elements are concerned (see German patent 703.484). However, these elements 10 have the disadvantage that they tend to become unusable by drying out. The invention aims to eliminate this disadvantage by using solutions as electrolytes which, under normal weather conditions, make drying out impossible or significantly delay it. As such an electrolyte, a concentrated magnesium chloride solution would be considered in the first place, which, as is known, is already used for the manufacture of elements 20 with manganese chloride pouches. However, with atmospheric oxygen elements using a magnesium chloride solution as an electrolyte, it appears that the separation of the basic zinc chloride in the pouch during discharge 25 exerts an adverse influence. These elements do not perform entirely satisfactorily with regard to capacity and load capacity. According to the invention, a concentrated manganese chloride solution is used as the electrolyte for atmospheric oxygen elements, which is free or virtually free of ammonia and / or ammonia salts. According to the invention, admixtures of, for example, alkaline earth chloride, preferably magnesium chloride, zinc chloride or similar substances may be added to the electrolyte. Such atmospheric oxygen elements possess a very high load capacity and a very large capacity when the pouch is properly loosely constructed. Manganese chloride is easily soluble in water and yields highly concentrated solutions which, due to their greatly reduced water vapor pressure, dry out much more difficultly than ammonium chloride solutions. By adding alkaline earth chloride, preferably magnesium chloride, solutions can be obtained whose water vapor pressure is even lower than that of pure concentrated manganese chloride solutions.In this way, it is possible to connect the water vapor pressure of the electrolyte to the 50. Available from the Industrial Property Office, The Hague — Price per item ƒ 1.— to adapt to local climatic conditions. The primary purpose of adding zinc chloride is to influence the nature of the electrolyte paste. The suitability of manganese chloride as an electrolyte remains even when it is used mixed with alkaline earth chloride, preferably magnesium chloride. An electrolyte obtained by mixing equal volume parts of a saturated magnesium chloride solution and a saturated manganese chloride solution, for example, still displays the action of the manganese chloride solution to a very strong degree; that is, such an element shows a higher load capacity, a steeper discharge curve, and a greater capacitance than an element manufactured with pure magnesium chloride as the electrolyte. If the manganese chloride content of the electrolyte is reduced even further, the action of the manganese chloride gradually diminishes until it finally ceases to exist, even with such small additions of manganese chloride to the magnesium chloride as are customary in the manufacture of magnesium chloromanganese chloride batteries for binding the developed chlorine. Tests with a battery consisting of 66 cells (EMF approx. 92.2 volts), which mainly contains concentrated manganese chloride solutions as an electrolyte, have shown that the terminal voltage during discharge across a resistor of 7000 ohms dropped from 90.2 volts to 40.2 volts only after 195 hours. Not only is this number of discharge hours 50% greater than that of a battery of cells containing a concentrated magnesium chloride solution as an electrolyte, but the terminal voltage is also higher throughout the entire discharge time. Atmospheric oxygen units containing a manganese chloride solution as an electrolyte can be stored for a long time because the low water vapor pressure greatly reduces drying out and because corrosion of the zinc does not occur during storage of the units or during rest periods between discharges. In "Die Fabrikation von Trockenbatterien und Blei-Akkumulatoren", C. Drotschman-PJMoll, Leipzig 1941, pp. 54, 72 and 75, the use of mixtures of sal ammoniac with manganese chloride solutions as an electrolyte for atmospheric oxygen supply and the spaces occupied by them is proposed. However, it has been shown that an equivalent amount of basic solutions is unsuitable, because it would be separated into self-chloride. The discharge of the elements composed with them therefore leads to much slower discharge. With atmospheric oxygen elements, the discharge does not appear to possess a noticeable depolarizing effect. The elements according to the invention, on the other hand, show throughout the entire period proceeding from the idea, the zinc oxide.to keep in solution for as long as possible the charge that forms during current delivery, in order to thereby obtain the greatest possible capacity of the elements to obtain the characteristic discharge curve of the charge. According to the invention, however, it has been shown that good results are also obtained when using manganese chloride as an electrolyte, without a delay in the separation of reaction products being to be expected under these conditions. This is probably explained by the fact that manganites separate in the pouch during discharge under the influence of air. These separations can separate the oxygen elements, which is desirable. A depolarizing effect of the separated manganites is not intended.

Claims

Conclusions.

1. Galvanic element, the positive air oxygen electrode of which made of activated carbon, charcoal or the like, the depolarization by oxygen can be detected. The presence of ammonia-causing substances exists, with moniace is in no way beneficial, the characteristic that manganese chloride is used as the electrolyte. and / or ammonium basic manganese hydroxide and higher acid salts. oxide formed, which can bind the cations.

2. Galvanic element according to claim 1, with As a result, an increase in the pn value is prevented from occurring in the electrolyte admixtures in the pouch during discharge, for example, alkaline earth metal chloride, it is preferentially or strongly limited, and also a decrease in the voltage of magnesium chloride, zinc chloride or the like is avoided. In addition, the water binders seem to have been added. Application no. 112627