GB1491929A - Electrochemical cells having solid electrolyte of tubular form - Google Patents

Abstract

1491929 Constraining electrolyte tube in Na - S cells CHLORIDE SILENT POWER Ltd 19 Aug 1976 [27 Aug 1975] 35406/75 Heading H1B An electrochemical cell, e.g. a Na-S cell having a tube of solid electrolyte material, e.g. B alumina separating a liquid alkali metal from a cathodic reactant wherein constraining means are provided around the electrolyte tube, the constaining means having a coefficient of thermal expansion such as to provide an increasing inward pressure on the electrolyte tube as the temperature rises. The constraining means may be provided by wire hoops, continuous wire, perforated sheet metal, e.g. low expansion Fe-Ni or Fe-Ni-Co alloy, sodium resistant glass fibres or carbon fibre having a coefficient of thermal expansion less than that of the B alumina tube and surrounding the tube. Alternatively the tube may be located in a housing having a relatively low coefficient of thermal expansion, e.g. ferritic stainless steel, low expansion Fe-Ni or Fe-Ni-Co alloy, Co, Ni, Nb, Mo, Zr or alloys thereof and elements of relatively high coefficient of thermal expansion, e.g. Al or Cu located between the housing and tube whereby the difference in coefficient of thermal expansion between the element and housing produces the required constraint on the electrolyte tube. The elements may be in the form of a perforated ruffle, Figs. 1 and 2, cylinders Fig. 3 or ceramic, vitreous, alkali or alkaline earth metal powder, e.g. calcium fluoride Fig. 4.