Patent EP0053441A1 successfully refreshed from Google Patents.
US4772293A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of electrochemical cells
Assignee: Lilliwyte SA
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Filing: 1987-04-21
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Granted: 1988-09-20
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Expires: 2007-04-21
Abstract
Abstract The invention provides a method of manufacturing an electrochemical cell housing wherein a beta-alumina tube has an open end attached to a casing via an alpha-alumina ring. In the method the alpha-alumina ring is thermocompression bonded to a metal ring by hot isostatic pressing, the alpha-alumina ring is then glass welded to the open end of the tube, and the metal ring is metal welded to the casing. The invention also provides a cell housing wherein a beta-alumina tube is located in spaced relationship within a metal casing. The tube is glass welded to an alpha-alumina ring which is thermocompression bonded on a curved radially facing surface thereof to a metal ring, the metal ring being metal welded to the casing.
Inventors
- 👤 Walter G. Bugden
- 👤 Peter R. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:52
CPC Classifications
H; H01; H01M; H01M50/00; H01M50/10; H01M50/147; H01M50/148; H01M50/1535; H01M10/00; H01M10/36; H01M10/39; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49108
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
169 words
In the manufacture of an electrochemical cell housing comprising a beta-alumina tube located within an outer metal casing wherein the tube has an open end and is attached to the casing via an annular alpha-alumina ring at said open end, the alpha-alumina ring being hollow-cylindrical in shape and having a pair of flat end faces, a cylindrical radially inner curved surface and cylindrical outer curved surface, by a method which includes the step of thermocompression bonding the alpha-alumina ring to at least one metal ring, and of thereafter attaching the alpha-alumina ring to the open end of the beta-alumina tube by glass welding and attaching at least one said metal ring by metal welding to the casing or to a metal closure for the tube, the improvement whereby the thermocompression bonding is effected by hot isostatic pressing by means of a fluid under pressure, the pressure being exerted in a radial direction and the metal ring being bonded to one of the cylindrical curved surfaces of the alpha-alumina ring.
Claim 2
Dependent Claim
169 words
In the manufacture of an electrochemical cell housing comprising a beta-alumina tube located within an outer metal casing wherein the tube has an open end and is attached to the casing via an annular alpha-alumina ring at said open end, the alpha-alumina ring being hollow-cylindrical in shape and having a pair of flat end faces, a cylindrical radially inner curved surface and cylindrical outer curved surface, by a method which includes the step of thermocompression bonding the alpha-alumina ring to at least one metal ring, and of thereafter attaching the alpha-alumina ring to the open end of the beta-alumina tube by glass welding and attaching at least one said metal ring by metal welding to the casing or to a metal closure for the tube, the improvement whereby the thermocompression bonding is effected by hot isostatic pressing by means of a fluid under pressure, the pressure being exerted in a radial direction and the metal ring being bonded to one of the cylindrical curved surfaces of the alpha-alumina ring.
Claim 3
Dependent Claim
126 words
A method as claimed in claim 1, which includes simultaneously thermocompression bonding two metal rings to the alpha-alumina ring by said hot isostatic pressing in a radial direction, one to the radially inner cylindrical curved surface of the alpha-alumina ring and one to the radially outer cylindrical curved surface thereof, the method including metal welding the radially inner metal ring to a metal closure to close off said open end of the tube and metal welding the radially outer metal ring to the casing, and the method further including forming a circumferentially extending axially facing groove in the alpha-alumina ring between the metal rings, locating the open end of the beta-alumina tube in said groove, and glass welding said open end in position in said groove.
Claim 4
Dependent Claim
90 words
A method as claimed in claim 1, in which a plurality of alpha-alumina tubes are simultaneously each thermocompression bonded to two metal rings formed prior to the glass welding thereof to beta-alumina tubes, by locating an alpha-alumina ring concentrically between a pair of metal tubes, thermocompression bonding the metal tubes simultaneously to the alpha-alumina ring by hot isostatic pressing to form a composite assembly, and then slicing the composite assembly into a plurality of annular slices, each of which slices comprises an alpha-alumina ring thermocompression bonded to two metal rings.
Claim 5
Dependent Claim
70 words
A method as claimed in claim 3, in which the alpha-alumina ring is a composite tube and is formed by stacking a plurality of alpha-alumina tubes end-to-end, and in which the slicing is into slices which each comprise a pair of alpha-alumina tubes located between a pair of metal rings, one of the alpha-alumina tubes being removed and discarded before the slice is attached to the beta-alumina tube and casing.
Claim 6
Dependent Claim
70 words
A method as claimed in claim 3, in which the annular space between the metal tubes which is occupied by the alpha-alumina ring is evacuated of gas prior to the thermocompression bonding, opposite ends of the annular space occupied by the alpha-alumina ring being closed off by welding annular closures to the ends of the metal tubes to seal said annular space under a vacuum prior to said thermocompression bonding.
Claim 7
Dependent Claim
63 words
A method as claimed in claim 5, which includes the step of loading a getter material into the interior of said annular space prior to the sealing, the getter material acting to resist a pressure build-up in said annular space during the thermocompression bonding by gettering at least some of such gases as are evolved in said interior during the hot isostatic pressing.
Claim 8
Dependent Claim
37 words
A method as claimed in claim 1, which includes the step of providing, on each metal surface which is to be thermocompression bonded to alpha-alumina by the hot isostatic pressing, a continuous coating of a different metal.
Claim 9
Dependent Claim
39 words
A method as claimed in claim 7, in which the metal surface is a nickel surface, the coating is at most 2 microns thick and the different metal is a member of the group comprising platinum, gold and copper.
Claim 10
Dependent Claim
42 words
A method as claimed in claim 1, which includes the step of forming on each metal surface which is to be thermocompression bonded to alpha-alumina by the hot isostatic pressing, a layer of oxide of the metal less than 1 micron thick.
Claim 11
Dependent Claim
26 words
A method as claimed in claim 9, in which forming the oxide layer is by heating the metal at an elevated temperature in an oxidizing atmosphere.
Claim 12
Dependent Claim
24 words
A method as claimed in claim 10, in which the heating is at a temperature of at least 250° C. and is in air.
Claim 13
Dependent Claim
13 words
A method as claimed in claim 9, in which the metal is nickel.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-20 | 1992-03-21 | 1992-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-20 | 1996-03-21 | 1996-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-20 | 2000-03-21 | 2000-09-20 | $7700.00 | Window Closed / Lapsed |