Electrochemical hydrogen pump

Patent metadata

Field	Value
Publication number	US-11577196-B2
Application number	US-201916503661-A
Country	US
Kind code	B2
Filing date	Jul 5, 2019
Priority date	Jul 23, 2018
Publication date	Feb 14, 2023
Grant date	Feb 14, 2023

Abstract

An electrochemical hydrogen pump includes an electrolyte membrane, an anode catalyst layer, a cathode catalyst layer, an anode gas diffusion layer, a cathode gas diffusion layer, an anode separator, a cathode separator, a first end plate and a second end plate that are disposed on the respective ends of at least one hydrogen pump unit in which the electrolyte membrane, the catalyst layers, the gas diffusion layers, and the separators are stacked on each other, a fastener that fastens the end plates and at least one hydrogen pump unit, and a voltage applier. The electrochemical hydrogen pump transfers hydrogen from the anode catalyst layer to the cathode catalyst layer and pressurizes hydrogen when the voltage applier applies the voltage. The cathode gas diffusion layer includes a water-repellent carbon fiber layer in a main surface thereof that is on a side of the cathode catalyst layer, and is compressed by the fastener.

First claim

What is claimed is:

1. An electrochemical hydrogen pump comprising:
an electrolyte membrane;
an anode catalyst layer disposed on one main surface of the electrolyte membrane;
a cathode catalyst layer disposed on another main surface of the electrolyte membrane;
an anode gas diffusion layer disposed on the anode catalyst layer;
a cathode gas diffusion layer disposed on the cathode catalyst layer;
an anode separator disposed on the anode gas diffusion layer;
a cathode separator disposed on the cathode gas diffusion layer,
a first end plate and a second end plate that are disposed on respective ends of at least one hydrogen pump unit in a stacking direction in which the electrolyte membrane, the anode catalyst layer, the cathode catalyst layer, the anode gas diffusion layer, the cathode gas diffusion layer, the anode separator, and the cathode separator are stacked on each other in the at least one hydrogen pump unit;
a fastener that fastens the at least one hydrogen pump unit, the first end plate, and the second end plate in the stacking direction; and
a voltage applier that applies a voltage between the anode catalyst layer and the cathode catalyst layer, wherein:
the electrochemical hydrogen pump transfers, to the cathode catalyst layer, hydrogen in a hydrogen-containing gas that has been supplied to the anode catalyst layer and pressurizes the hydrogen when the voltage applier applies the voltage,
the cathode gas diffusion layer includes a water-repellent carbon fiber layer in a main surface of the cathode gas diffusion layer that is on a side of the cathode catalyst layer, and is compressed due to fastening of the fastener,
during a hydrogen pressurizing operation of the electrochemical hydrogen pump, the electrolyte membrane, the anode catalyst layer, and the anode gas diffusion layer are compressed causing a distortion of the electrolyte membrane, the anode catalyst layer, and the anode gas diffusion layer, where the higher a pressure in the electrochemical hydrogen pump is, the larger the distortion is, and
an amount of compression of the cathode gas diffusion layer in the stacking direction due to fastening of the fastener is equal to or larger than a sum of amounts of the distortion of the electrolyte membrane, the anode catalyst layer, and the anode gas diffusion layer in the stacking direction under a maximum pressure of the electrochemical hydrogen pump.

2. The electrochemical hydrogen pump according to claim 1 , wherein the amount of compression of the cathode gas diffusion layer in the stacking direction due to fastening of the fastener is 20% to 30% of a thickness of the cathode gas diffusion layer before fastening of the fastener.

3. The electrochemical hydrogen pump according to claim 1 , wherein the amount of compression of the cathode gas diffusion layer in the stacking direction due to fastening of the fastener is equal to or larger than 10% of a thickness of the cathode gas diffusion layer before fastening of the fastener.

4. The electrochemical hydrogen pump according to claim 1 , comprising a water-repellent layer containing a water-repellent resin and carbon black on a main surface of the water-repellent carbon fiber layer that is on the side of the cathode catalyst layer.

5. The electrochemical hydrogen pump according to claim 1 , wherein, in a main surface of the water-repellent carbon fiber layer that is on the side of the cathode catalyst layer, the water-repellent carbon fiber layer includes a mixture layer in which the water-repellent carbon fiber layer and a water-repellent layer containing a water-repellent resin and carbon black are mixed together.

6. The electrochemical hydrogen pump according to claim 1 , wherein the anode gas diffusion layer includes a metal sheet including a plurality of ventilation pores and does not include the carbon fiber layer.

7. The electrochemical hydrogen pump according to claim 6 , wherein the anode gas diffusion layer includes a water-repellent layer in a main surface of the anode gas diffusion layer that is on a side of the anode catalyst layer.

8. The electrochemical hydrogen pump according to claim 1 , wherein the at least one hydrogen pump unit includes a plurality of the hydrogen pump units.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Ukai Kunihiro
• Nakaue Takayuki
• Wakita Hidenobu

Classifications

• H01M4/9083

  on carbon or graphite · CPC title

• C25B11/051

  Electrodes formed of electrocatalysts on a substrate or carrier · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• B01D53/326 Primary

  in electrochemical cells · CPC title

• H01M8/248

  Means for compression of the fuel cell stacks · CPC title