Seal for an electrochemical device, process for manufacturing and fitting the seal and this device

Patent metadata

Field	Value
Publication number	US-2016285113-A1
Application number	US-201415037158-A
Country	US
Kind code	A1
Filing date	Dec 2, 2014
Priority date	Dec 4, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A seal is mountable in contact with two metal carriers of an electrochemical device, in particular a solid oxide fuel cell (SOFC) or a high-temperature solid oxide electrolyser cell (SOEC) for electrolysis of water vapour. This seal comprises a means for making the seal impermeable, comprising at least one vitreous material; and an electrically insulating supporting means that supports the impermeable means and that has two parallel main faces, an external peripheral edge and an internal peripheral edge, the seal being able to be mounted against these carriers via these main faces, which are covered with the impermeable means. The impermeable means partitions the supporting means between these internal and external edges while extending continuously from one of the main faces to the other through the supporting means, so that the impermeable means directly connects these carriers to each other.

First claim

1 . A seal gasket which may be used for being mounted in contact with two metal spans of an electrochemical device in particular of the solid oxide fuel cell (SOFC) type or solid oxide high temperature steam electrolyzer (SOEC) type, the gasket comprising:
a sealing means of the gasket comprising at least one material of the glass or vitroceramic type, and a supporting means electrically insulating, which supports the sealing means and which has two main parallel faces, an external peripheral edge and an internal peripheral edge, the gasket being able to be mounted against these spans through these main faces, which are at least partly covered with the sealing means, wherein the sealing means partitions the supporting means between said internal peripheral edge and said external peripheral edge by continuously extending from one of said main faces to the other through the supporting means, so that the sealing means directly connects these spans to each other.

2 . The gasket according to claim 1 , wherein the supporting means comprises a one-piece frame in a porous material which is machined so as to define perforated surfaces through the frame forming at least one through-channel with a predetermined geometry receiving the sealing means, said at least one channel filled with the sealing means forming at least one sealed partition continuously extending from one of said main faces to the other.

3 . The gasket according to claim 2 , wherein said surfaces of said at least one channel are globally perpendicular to said main faces and extend in a peripheral direction globally concentric with said internal and external peripheral edges, continuously or discontinuously along said peripheral direction, tabs consisting of said frame being formed on either side of said at least one channel for connecting the latter to the remainder of the frame or to another so called adjacent channel, each tab having a volume of less than the one of said at least one channel.

4 . The gasket ( 40 , 60 ) according to claim 3 , characterized in that wherein said tabs ( 43 , 63 ) are angularly shifted radially on either side of said at least one channel ( 25 , 26 ), for example along a staggered arrangement, so as to maximize the length of the path of gases distributed by interconnectors ( 28 and 29 ) formed by said spans and/or the pressure drops for these gases through said porous material of said frame ( 44 , 64 ).

5 . The gasket according to claim 3 , wherein said at least one sealed partition extends continuously in said peripheral direction, said tabs extending on either side of said at least one channel respectively towards said external peripheral edge and towards said internal peripheral edge.

6 . The gasket according to claim 5 , wherein the gasket comprises at least two said concentric seal partitions which are connected pairwise to each other through said radial tabs.

7 . The gasket according to claim 3 , wherein said at least one sealed partition extends discontinuously in said at least one peripheral direction while forming a plurality of partitioning portions.

8 . The gasket according to claim 7 , wherein the gasket comprises at least two so called sealed partitions each formed with said plurality of partitioning portions accommodated in said channels crossing said frame which are machined according to curvilinear, rectilinear, undulated geometries and/or as broken lines and which are filled with the sealing means, these partitioning portions being connected pair wise with each other in the peripheral direction through said tabs.

9 . The gasket according to claim 7 , wherein the gasket comprises a multitude of said sealed partitions which are respectively formed with a multitude of holes crossing said frame, for example cylindrical holes, which form said channels machined at regular intervals between said internal peripheral edge and said external peripheral edge and which are filled with the sealing means.

10 . The gasket according to claim 1 , wherein the sealing means is based on glass or vitroceramic, and in that the supporting means consist of a machined sheet in a porous material selected from the group formed by porous ceramics and porous minerals, preferably mica.

11 . A method for manufacturing and assembling a gasket according to claim 1 in an electrochemical device in particular of the solid oxide fuel cell (SOFC) type or solid oxide high temperature steam electrolyzer (SOEC) type, wherein the method comprises:
(a) machining of the supporting means for perforating said at least one channel between said internal peripheral edge and said external peripheral edge which continuously extends from one of said main faces to the other through the supporting means,
(b) depositing the sealing means, such as a glass paste, onto said main faces and in said at least one channel for obtaining a blank of the gasket before assembling; and
c) assembling the gasket within a stack of at least one cell of the device at a temperature comprised between 600° C. and 900° C. and under an applied pressure of several kPa, in order to melt the sealing means while setting the sealing means into place.

12 . An electrochemical device of the solid oxide fuel cell (SOFC) type or solid oxide high temperature steam electrolyzer (SOEC) type, the device comprising:
at least one cell which comprises a hydrogen electrode-electrolyte-oxygen electrode assembly and which delimits two chambers, at least two electric contact elements with said at least one cell respectively positioned in contact with said electrodes, at least two metal spans forming interconnectors which distribute into said at least one cell an electric current and gases such as steam, dioxygen, dihydrogen and optionally a carrier gas and which, in the case of several of said cells, ensure the junction between the latter; and seal gaskets which are each mounted in contact with a pair of said interconnectors, wherein at least one of said gaskets is a gasket according to claim 1 .

13 . The electrochemical device according to claim 12 , wherein the whole of said gaskets are electrically insulating and comprise first gaskets ensuring the seal between the chambers of said at least one cell, second gaskets ensuring the seal between respective supplies of inlet gases, and outlet gases and third gaskets ensuring the seal of said at least one cell with the outer atmosphere, said second and third gaskets each comprising:
a sealing means of the gasket comprising at least one material of the glass or vitroceramic type, and a supporting means electrically insulating, which supports the sealing means and which has two main parallel faces, an external peripheral edge and an internal peripheral edge, the gasket being able to be mounted against these spans through these main faces, which are at least partly covered with the sealing means, wherein the sealing means partitions the supporting means between said internal peripheral edge and said external peripheral edge by continuously extending from one of said main faces to the other through the supporting means, so that the sealing means directly connects these spans to each other.

Assignees

• Commissariat Energie Atomique

Inventors

• Di Iorio Stéphane
• Oresic Bruno
• Petit Julien
• Reytier Magali

Classifications

• H01M8/028

  Sealing means characterised by their material · CPC title

• H01M8/2457

  with both reactants being gaseous or vaporised · CPC title

• H01M8/0286

  Processes for forming seals · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M8/2425

  High-temperature cells with solid electrolytes · CPC title