SU740169A3 - Rechargeable zinc-halogen current source - Google Patents

Abstract

1485763 Separators for zinc-halogen cells UNIGATE Ltd 19 Aug 1974 [24 Aug 1973] 40299/73 Heading H1B A rechargeable zinc-halogen cell comprises a casing containing zinc anodes, halogen storage carbon/metal cathodes, a halogen gas inlet to the casing and a semi-permeable separator between each cathode and anode to prevent the passage through the separator of the halogen in solution. The separator enables the pH value of the electrolyte such as zinc chloride to be maintained at different values adjacent the cathode and anode. The halogen is preferably chlorine but may be iodine or bromine and the separator allows the passage of zinc and chloride ions but prevents the passage of chlorine molecules in solution. The membrane is of the radiation cross-graft type.

Description

The invention relates to chemical current sources, in particular rechargeable zinc-halogen current sources.

A zinc-halogen current source is known, comprising a housing with a fossil chamber, a positive carbon-based electrode, a negative electrode in the form of a zinc-coated substrate, a solution of the corresponding zinc halide as an electrolyte, and a container with the corresponding halogen 1j.

However, such a current source has a large self-discharge and cannot be recharged.

A rechargeable zinc halogen current source is known that is closest to the proposed current source by its technical essence and achievable result, comprising a housing with partitions, positive electrodes made of porous carbon deposited on a base of metal 1UA or UA groups of the Periodic Table of Elements, moving with negative zinc-supported electrodes, polymer separator, space above the halogen electrodes and electrolyte from

a solution of the corresponding zinc halide 2,

However, in such a current source in the process of charging with halogen, a noticeable amount of chlorine accumulates on the outer surface of the cathode and, if chlorine reaches the zinc-containing electrode, the latter undergoes corrosion, and there is a tendency to

10 times the fibers reducing the cposr service of the elolente, and the value of f) H elec-. the troll is about a dozen; ovym in the whole element. Preferred is a distinct pH difference.

1 & at the cathode and anode, for example, 1.0 and 2.0, respectively.

The purpose of the invention is to increase service life and increase efficiency by preventing dendritic formation.

For this, in the proposed current source, a polymer with a pore size of 2540 A. is taken as a separator.

25

Preferred is the use of sulfonated polyethylene having a high ionic selectivity as an expanded polymer.

In the proposed current source

30 The diffusion of chlorine in the cell can be reduced, and the pH of the electoolite can be maintained at the required and different values: near the cathode and the anode. At the same time significantly. fiber formation is reduced and the efficiency of the zinc anode increases. . . It is preferable to have a separator and a P-shaped sheet made and scTDoeHHoro to the current source so as to prevent diffusion of gaseous halogen. Such a separation ensures the passage of the koivtsyya and gaisch, for example, Reed, and prevents the passage of any dissolved halogen. The pore sizes of the dry film in these separators are 25–40 D, so they are fairly small in order to prevent the halogen molecules, HanptiMep chlorine, from passing into the solution. By using a separator of this type, it is possible to maintain the pH of the anolyte and the incubate at 1-2 pH Thus, qi becomes stable in terms of attribution of corrosion, the effectiveness of zinc coating is satisfactory for long periods of discharge and charge, and the formation of fibers on the anode is negligible. Formulation formula 1. Rechargeable zinc-halogen current source, comprising a housing with partitions, positive porous carbon specimens deposited on the base 113 of metal 1UA or UA groups of the Periodic Table of Elements, alternating with negative zinc electrodes applied on the base, polymer separator, above the electrodes for the halogen and the electrolyte from a solution of the corresponding zinc halide, in order to increase the service life and increase efficiency by preventing As a separator, a cross-linked diameter of 25-40A was taken as a separator. 2. The source of toranb p. 1, which is due to the fact that sulfonated polyethylene was used as a cross-linked polymer. Sources of information taken into account during the examination 1. Bagotsky V.S., Flerov V.N. Recent advances in chemical sources. Tosenergoizdat 1963, p. 138-142. 2 .. Patent of the USSR No. 357774, H 01 M 12/06, 02.21.69.

Claims (2)

Frrmula ^ acquisition 1. Rechargeable zinc-halogen containing current source ,, _z cor- pus with baffles of porous carbon positive electrodes are deposited on a substrate of metal or 1UA the V of the periodic table of elements, interspersed with 'negative electrodes of zinc deposited on the base polymer a separator, a space above the halogen electrodes, and an electrolyte from a solution of the corresponding zinc halide, which can be used in order to increase the service life and increase efficiency by preventing dendritic formation As a separator, a cross-linked polymer with a pore size of 25-40A was taken. 2. The current source according to claim 1, which is distinguished by the fact that sulfonated polyethylene is taken as a crosslinked polymer.