Glass seal for sodium-sulphur cells

摘要

The invention provides a method of sealing an alpha-alumina component to a beta-alumina component in an electrochemical cell, using a high-borate borosilicate glass. The glass comprises 10-25% by mass B2O3 and 65-75% siO2, with the major proportion by mass of the balance being Al2O3 and alkali metal oxide, and the glass comprising at most 1% by mass alkaline earth metal oxides. The invention also provides a hermetic seal of said glass between an alpha-alumina component and a beta-alumina component in an electrochemical cell; and such cell which incorporates said seal.