Electrolysis device, electrolysis system, and method of operating electrolysis device

Patent metadata

Field	Value
Publication number	US-2025092549-A1
Application number	US-202418596709-A
Country	US
Kind code	A1
Filing date	Mar 6, 2024
Priority date	Sep 19, 2023
Publication date	Mar 20, 2025
Grant date	—

Abstract

An electrolysis device includes: a first electrolysis cell to reduce a reducible material and oxidize an oxidizable material; a second electrolysis cell to reduce the reducible material and oxidize the oxidizable material; a first supply source to supply a first fluid containing gas of the reducible material to the cells; a second supply source to supply a second fluid containing liquid of the oxidizable material to the cells; and at least one power supply to supply a first and a second power supply current to the first and the second electrolysis cell respectively. The at least one power supply can set values of the first and second power supply currents so that a current density of current flowing through the second electrolysis cell when reducing the reducible material is higher than a current density of current flowing through the first electrolysis cell when reducing the reducible material.

First claim

What is claimed is:

1 . An electrolysis device comprising:
a first electrolysis cell configured to reduce a reducible material and to oxidize an oxidizable material; a second electrolysis cell configured to reduce the reducible material and to oxidize the oxidizable material; a first supply source configured to supply a first fluid to the first electrolysis cell and the second electrolysis cell, the first fluid containing a gas of the reducible material; a second supply source configured to supply a second fluid to the first electrolysis cell and the second electrolysis cell, the second fluid containing a liquid of the oxidizable material; and at least one power supply configured to supply a first power supply current to the first electrolysis cell and to supply a second power supply current to the second electrolysis cell, wherein the at least one power supply is configured to set a value of the first power supply current and a value of the second power supply current so that a current density of current flowing through the second electrolysis cell when reducing the reducible material is higher than a current density of current flowing through the first electrolysis cell when reducing the reducible material.

2 . The device according to claim 1 , wherein:
the first electrolysis cell has:
a first membrane electrode assembly having a first cathode, a first anode, and a first diaphragm between the first cathode and the first anode;
a first cathode flow path plate having a first cathode flow path facing on the first cathode; and
a first anode flow path plate having a first anode flow path facing on the first anode;
the second electrolysis cell has:
a second membrane electrode assembly having a second cathode, a second anode, and a second diaphragm between the second cathode and the second anode;
a second cathode flow path plate having a second cathode flow path facing on the second cathode; and
a second anode flow path plate having a second anode flow path facing on the second anode; and
the device further comprises: a first cathode current collector electrically connected to the first cathode and the at least one power supply; a first anode current collector electrically connected to the first anode and the at least one power supply; a second cathode current collector electrically connected to the second cathode and the at least one power supply; and a second anode current collector electrically connected to the second anode and the at least one power supply.

3 . The device according to claim 2 , wherein
the second cathode flow path is connected in series to the first cathode flow path.

4 . The device according to claim 2 , wherein
the second cathode flow path is connected in parallel to the first cathode flow path.

5 . The device according to claim 2 , wherein:
the at least one power supply includes a power supply configured to supply the first power supply current to the first electrolysis cell via the first cathode current collector and the first anode current collector and supply the second power supply current to the second electrolysis cell via the second cathode current collector and the second anode current collector; and the first cathode current collector, the first anode current collector, the second cathode current collector, and the second anode current collector are electrically connected to the power supply.

6 . The device according to claim 2 , wherein
the at least one power supply includes: a first power supply configured to supply the first power supply current to the first electrolysis cell via the first cathode current collector and the first anode current collector; and a second power supply configured to supply the second power supply current to the second electrolysis cell via the second cathode current collector and the second anode current collector.

7 . The device according to claim 1 , wherein:
the first fluid contains a first gas and a second gas; the first gas is gas of carbon dioxide; the second gas is gas of a substance different from the carbon dioxide; the first electrolysis cell and the second electrolysis cell reduce the carbon dioxide and reduce the substance; and a reduction potential of the carbon dioxide is higher than a reduction potential of the substance.

8 . The device according to claim 7 , wherein
the substance is oxygen.

9 . The device according to claim 7 , wherein
the substance is nitrogen.

10 . The device according to claim 7 , wherein
a concentration of the second gas of the first fluid is 1 ppm or higher and 100000 ppm or lower.

11 . The device according to claim 2 , further comprising
a third electrolysis cell between the second cathode current collector and the second anode current collector, wherein the third electrolysis cell having
a third cathode;
a third anode;
a third diaphragm between the third cathode and the third anode;
a third cathode flow path plate having a third cathode flow path facing on the third cathode; and
a fourth anode flow path plate having a third anode flow path facing on the third anode; and
the third cathode is electrically connected to the second anode, or the third anode is electrically connected to the second cathode.

12 . The device according to claim 2 , further comprising:
a first pipe configured to connect the first electrolysis cell and the second electrolysis cell, and supply the first fluid from the first cathode flow path to the second cathode flow path; and a second pipe configured to connect the first electrolysis cell and the second electrolysis cell, and supply the second fluid from the first anode flow path to the second anode flow path.

13 . The device according to claim 2 , wherein
the first cathode has a first catalyst; the second cathode has a second catalyst; and the first catalyst is different from the second catalyst.

14 . The device according to claim 2 , wherein:
the first fluid contains gas of carbon dioxide; the first electrolysis cell is configured to reduce carbon dioxide by the first cathode to produce a carbon compound; and the second electrolysis cell is configured to reduce the carbon dioxide by the second cathode to produce the carbon compound.

15 . The device according to claim 2 , wherein
the first fluid contains a gas of nitrogen; the first electrolysis cell is configured to reduce nitrogen by the first cathode to produce ammonia; and the second electrolysis cell is configured to reduce the nitrogen by the second cathode to produce the ammonia.

16 . The device according to claim 2 , wherein
the first electrolysis cell comprises:
a first membrane electrode assembly having the first cathode, the first anode, and the first diaphragm;
a first supporting plate surrounding the first membrane electrode assembly and having a first opening and a second opening;
a first cathode flow path plate having the first cathode flow path connected to the first opening, a third opening connected to the first cathode flow path, and a fourth opening connected to the second opening;
a first anode flow path plate having the first anode flow path connected to the second opening, a fifth opening connected to the first opening, and a sixth opening connected to the first anode flow path;
the first cathode current collector having a seventh opening connected to the third opening and an eighth opening connected to the fourth opening; and
the first anode current collector having a ninth opening connected to the fifth opening and a tenth opening connected to the sixth opening; and

Assignees

• Toshiba Kk

Inventors

• Yamagiwa Masakazu
• Kudo Yuki
• Kiyota Yasuhiro
• Ono Akihiko
• Yonetsu Maki
• Kitagawa Ryota
• Mikoshiba Satoshi

Classifications

• C25B9/70

  Assemblies comprising two or more cells · CPC title

• C25B3/25

  Reduction · CPC title

• C25B1/27

  Ammonia · CPC title

• C25B3/26

  of carbon dioxide · CPC title

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title