Conductive sheets, membrane electrode assemblies, and fuel cells

Abstract

To provide conductive sheets, membrane electrode assemblies, and fuel cells that suppress the degradation of polymer electrolyte membranes and the decline in battery performance. [Solution] A conductive sheet; a membrane electrode assembly and a fuel cell comprising a carbon-based conductive material containing carbon-based conductive fibers having an average fiber diameter of 0.1 μm or more and 0.9 μm or less, and a fluororesin, wherein the content of the fluororesin is more than 1% by mass and 35% by mass or less relative to the total solid content of the conductive sheet, and the maximum peak in the pore size distribution is 0.1 μm or more and 5.0 μm or less.

Claims

1. The material comprises a carbon-based conductive material containing carbon-based conductive fibers having an average fiber diameter of 0.1 μm or more and 0.9 μm or less, and a fluororesin. A conductive sheet in which the fluororesin content is greater than 1% by mass and less than or equal to 35% by mass relative to the total solid content of the conductive sheet, and the maximum peak in the pore size distribution is between 0.1 μm and 5.0 μm.

2. The conductive sheet according to claim 1, wherein the carbon-based conductive fiber has an aspect ratio (average fiber length / average fiber diameter) of 20 or more and 100 or less.

3. The conductive sheet according to claim 1, wherein the maximum peak of the pore size distribution in the thickness direction is uniform, and the conductive sheet is a single-layer conductive sheet for a gas diffusion layer.

4. A conductive sheet according to claim 1, for use as a gas diffusion electrode.

5. Polymer electrolyte membrane, The system comprises a pair of gas diffusion electrodes that sandwich the polymer electrolyte membrane, A film electrode assembly wherein at least one of the pair of gas diffusion electrodes includes a conductive sheet according to any one of claims 1 to 4.

6. Thickness T of the polymer electrolyte membrane ＩＯＮ (μm) and the thickness T of the gas diffusion electrode ＧＤＥ Ratio (T) to (μm) ＩＯＮ / T ＧＤＥ The membrane electrode assembly according to claim 5, wherein the coefficient of the coefficient is 0.05 or more and 1.00 or less.

7. The membrane electrode assembly according to claim 5, Separator and, A fuel cell equipped with a fuel cell.

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