Direct methanol fuel cell
AssigneePanasonic Corporation
InventorsHideyuki Ueda, Shinsuke Fukuda
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Abstract
A direct methanol fuel cell of the present invention includes a unit cell having an electrolyte membrane, an anode on one surface of the electrolyte membrane, and a cathode on the other surface of the electrolyte membrane. The anode includes an anode catalyst layer and an anode diffusion layer. The anode catalyst layer is in contact with a surface of the electrolyte membrane. The anode diffusion layer is in contact with a surface of the anode catalyst layer opposite to the surface of the anode catalyst layer in contact with the electrolyte membrane. A methanol flux value JGDL of the anode diffusion layer and a methanol flux value JPEM of the electrolyte membrane satisfy the following relations: JGDL=1×10−5 to 5×10−4 mol/(cm2·min.), (i) and JPEM×JGDL≦1×10−8 [mol/(cm2·min.)]2. (ii)
Claims7
A direct methanol fuel cell comprising a unit cell having an electrolyte membrane, an anode on one surface of said electrolyte membrane, and a cathode on an other surface of said electrolyte membrane,
- said anode comprising an anode catalyst layer and an anode diffusion layer,
- said anode catalyst layer being in contact with a surface of said electrolyte membrane,
- said anode diffusion layer being in contact with a surface of said anode catalyst layer opposite to said surface of said anode catalyst layer in contact with said electrolyte membrane,
- wherein a methanol flux value JGDL of said anode diffusion layer and a methanol flux value JPEM of said electrolyte membrane satisfy the following relations:
- JGDL=1×10−5 to 5×10−4 mol/(cm2·min.), (i)
- JPEM≧2×10−5 mol/(cm2·min.), (ii)
- and
- JPEM×JGDL≦1×10−8 [mol/(cm2·min.)]2 (iii).
A method for generating power using a direct methanol fuel cell comprising a unit cell having an electrolyte membrane, an anode on one surface of said electrolyte membrane, and a cathode on an other surface of said electrolyte membrane, said anode comprising an anode catalyst layer and an anode diffusion layer, said anode catalyst layer being in contact with a surface of said electrolyte membrane, said anode diffusion layer being in contact with a surface of said anode catalyst layer opposite to said surface of said anode catalyst layer in contact with said electrolyte membrane, said method comprising the steps of:
- (a) selecting an anode diffusion layer and an electrolyte membrane such that a methanol flux value JGDL of said anode diffusion layer and a methanol flux value JPEM of said electrolyte membrane, which are measured by allowing said anode diffusion layer and said electrolyte membrane to come into contact with an aqueous solution having a certain methanol concentration at a certain temperature, satisfy the following relations:
- JGDL=1×10−5 to 5×10−4 mol/(cm2·min.), (i)
- JPEM≧2×10−5 mol/(cm2·min.), (ii)
- and
- JPEM×JGDL≧1×10−5 [mol/(cm2·min.)]2 (iii)
- (b) determining a concentration of methanol to be contained in fuel and a temperature for operating said fuel cell based on the temperature and the methanol concentration used for said measurement of said JGDL and said JPEM;
- and
- (c) generating power at said temperature determined in said step (b) by feeding fuel containing methanol at the concentration determined in said step (b) to said anode.
A direct methanol fuel cell comprising a unit cell having an electrolyte membrane, an anode on one surface of said electrolyte membrane, and a cathode on an other surface of said electrolyte membrane,
- said anode comprising an anode catalyst layer and an anode diffusion layer,
- said anode catalyst layer being in contact with a surface of said electrolyte membrane,
- said anode diffusion layer being in contact with a surface of said anode catalyst layer opposite to said surface of said anode catalyst layer in contact with said electrolyte membrane,
- wherein a methanol flux value JGDL of said anode diffusion layer and a methanol flux value JPEM of said electrolyte membrane satisfy the following relations:
- JGDL=1×10−5 to 5×10−4 mol/(cm2·min.), (i)
- JPEM≧2×10−5 mol/(cm2·min.), (ii)
- and
- JPEM×JGDL≦1×10−8 [mol/(cm2·min.)]2, (iii)
- said anode diffusion layer has an air permeability QAir of 200 to 1000 cc/(cm2·min.·kPa),
- a surface layer having a porous structure is formed on a surface of said anode diffusion layer, and
- said surface layer comprises at least one of a mixture of a water repellent resin fine particle and a water repellent binder material, and a mixture of an electron conductive porous material and a water repellent binder material.
Dependencies are inferred from the claim text.