Electro-chemical reaction unit having glass seal member composed of vertically long crystal grains, and electro-chemical reaction cell stack, and electro-chemical reaction unit production method comprising same
An electrochemical reaction unit includes a unit cell including an electrolyte layer, and a cathode and an anode which face each other in a first direction with the electrolyte layer intervening therebetween, and one or a plurality of structural members. The electrochemical reaction unit further includes a glass seal member which contains glass and is in contact with two members facing each other in the first direction, the two members being selected from the unit cell and the one or the plurality of structural members. The glass seal member contains a plurality of crystal grains each having a ratio of a vertical dimension in the first direction to a horizontal dimension in a second direction orthogonal to the first direction of 1.5 or more.
1. An electrochemical reaction unit comprising:
a unit cell including an electrolyte layer, and a cathode and an anode which face each other in a first direction with the electrolyte layer intervening therebetween; and
one or a plurality of structural members,
the electrochemical reaction unit being characterized by
further comprising a glass seal member which contains glass and is in contact with two members facing each other in the first direction, the two members being selected from the unit cell and the one or the plurality of structural members, and characterized in that
the glass seal member contains a plurality of glass crystal grains each having a ratio of a vertical dimension in the first direction to a horizontal dimension in a second direction orthogonal to the first direction of 1.5 or more.
2. An electrochemical reaction unit according to claim 1 , wherein
the two members are the unit cell, and the structural member which at least partially faces the unit cell in the first direction.
3. An electrochemical reaction unit according to claim 2 , wherein
the structural member which faces the unit cell is a separator which has a through hole formed therein; whose portion around the through hole is joined to a peripheral portion of the unit cell; and which separates from each other a cathode chamber facing the cathode and an anode chamber facing the anode.
4. An electrochemical reaction unit according to claim 1 , wherein
the two members are a first structural member and a second structural member which face each other in the first direction.
5. An electrochemical reaction unit according to claim 4 , wherein
one of the first structural member and the second structural member is an interconnector.
6. An electrochemical reaction unit according to claim 1 , wherein
the vertical dimension of at least one of the glass crystal grains is 30% or more of a thickness of the glass seal member in the first direction.
7. An electrochemical reaction unit according to claim 1 , wherein
the vertical dimension of at least one of the glass crystal grains is 50% or more of a thickness of the glass seal member in the first direction.
8. An electrochemical reaction cell stack comprising a plurality of electrochemical reaction units,
the electrochemical reaction cell stack being characterized in that at least one of the electrochemical reaction units is an electrochemical reaction unit according to claim 1 .
9. A production method for an electrochemical reaction unit which includes
a unit cell including an electrolyte layer, and a cathode and an anode facing each other in a first direction with the electrolyte layer intervening therebetween,
one or a plurality of structural members, and
a glass seal member containing glass and being in contact with two members facing each other in the first direction, the two members being selected from the unit cell and the one or the plurality of structural members, and in which
the glass seal member contains a plurality of glass crystal grains each having a ratio of a vertical dimension in the first direction to a horizontal dimension in a second direction orthogonal to the first direction of 1.5 or more, the method comprising:
a step of preparing the unit cell and the one or the plurality of structural members;
a step of disposing between the two members a seed layer containing at least one element of Ba, Ca, Mg, Al, La, Ti, Cr, Zr, and Ce, and glass; and
a step of forming the glass seal member by, in a state in which the seed layer and the glass are disposed between the two members, melting the glass, followed by crystallization.
10. A production method for an electrochemical reaction unit according to claim 9 , wherein
the two members are the unit cell, and the structural member which at least partially faces the unit cell in the first direction.
11. A production method for an electrochemical reaction unit according to claim 9 , wherein
the two members are a first structural member and a second structural member which face each other in the first direction.
12. An electrochemical reaction unit according to claim 1 , wherein the ratio is 1.5 or more and less than 10.
13. A production method for an electrochemical reaction unit according to claim 9 , wherein the ratio is 1.5 or more and less than 10.