Catalyst layer for fuel cell
AssigneeToyota Jidosha Kabushiki Kaisha
InventorNobuaki MIZUTANI
Life of this patent
Estimating the term…
Abstract
The catalyst layer for a fuel cell includes at least a base material, a carbon support, and a catalyst metal. A specific surface area of the carbon support is 1000 to 1500 m2/g. The thickness loss rate A of the catalyst layer represented by the expression (I) is 45% or less. The deformation rate B of the catalyst layer represented by the expression (II) is 50% or less. A = ( 1 - T 1 / T 0 ) × 100 ( I ) B = D i / T 0 × 1 0 0 ( II ) T0 is an initial thickness of the catalyst layer. T1 is a thickness of the catalyst layer after a durability treatment. Di is a deformation amount obtained as an inflection point of a load variation curve obtained by a micro-burst test of the catalyst layer. The durability treatment is performed under conditions described in the specification or the claims.
Claims5
A catalyst layer for a fuel cell, the catalyst layer comprising at least:
- a base material;
- a carbon support disposed on a surface of the base material;
- and
- a catalyst metal supported on the carbon support, wherein:
- a specific surface area of the carbon support is in a range of 1000 m2/g to 1500 m2/g;
- a thickness loss rate A (%) of the catalyst layer represented by the following expression (I) is 45% or less;
- and
- a deformation rate B (%) of the catalyst layer represented by the following expression (II) is 50% or less,
- A
-
- (
- %
- )
- =
- (
- 1
- -
- T
- 1
- /
- T
- 0
- )
- ×
- 100
- (
- I
- )
- B
-
- (
- %
- )
- =
- D
- i
- /
- T
- 0
- ×
- 1
-
- 0
-
- 0
- (
- II
- )
- in the expression (I) and the expression (II),
- T0 is an initial thickness (μm) of the catalyst layer,
- T1 is a thickness (μm) of the catalyst layer after a durability treatment,
- Di is a deformation amount (μm) obtained as an inflection point of a load variation curve obtained by a micro-burst test of the catalyst layer, and
- the durability treatment is performed by producing a membrane electrode assembly in which the catalyst layer is used as either or both of a cathode and an anode, and performing, using the membrane electrode assembly as a single cell, a steady operation at 1 V to 1.5 V for 1 hour to 5 hours under conditions of a constant flow rate of H2/N2 gas, a cell temperature of 70° C. to 90° C., an anode (hydrogen) dew point of 70° C. to 90° C., a cathode (air) dew point of 70° C. to 90° C., and a back pressure of 50 kPa to 150 kPa (absolute value).
Dependencies are inferred from the claim text.