SEALING OF ELECTRO-CHEMICAL DEVICES UTILISING LIQUID SODIUM AND A SOLID CERAMIC ELECTROLYTE PERMEABLE TO SODIUM ION

摘要

1502693 Na-S cell; Nb protective seal CHLORIDE SILENT POWER Ltd 7 Feb 1977 [9 Feb 1976] 05030/76 Heading H1B An Na-S cell (Fig. 1) has a protective layer or film of Nb, 15, secured to an outer metal tubular housing 14 composed of, for example, Ni-Fe alloys, to protect the bond between the housing and a sodium resistant glass seal, 13, from degradation by Na vapour in anodic compartment 18. In Fig. 1, 10 is the upper part of a beta-Al 2 O 3 tube, secured at its top end to an alpha-Al 2 O 3 flange 11 by a glass seal 12. Alternatively, Fig. 3, the alpha-Al 2 O 3 flange may be dispensed with, the seal being effected by glass 23 bonding 10 to a nickel-iron ring 24 which in turn is welded at 25 to a cylindrical steel casing 14; the ring is plated with Nb at 26 where the glass-metal interface is exposed to Na vapour. The Nb film may be electroplated or vapour deposited on the base metal member; the coating being preferably from 10 to 200 Ám.