Method for determining good-quality product of electrode ink
According to the present invention, in an electrode ink, ionomers are adsorbed around a catalyst carrier to form a primary aggregate which does not aggregate with another catalyst carrier, and catalyst carriers aggregate together to form a secondary aggregate. In this method for determining a good-quality product of an electrode ink, the modulus of elasticity of the electrode ink is detected. Furthermore, on the basis of the modulus of elasticity, the states of the primary aggregate and the secondary aggregate in the electrode ink are estimated, and, if the contained amount of the primary aggregate is greater than that of the secondary aggregate, the electrode ink is determined to be good-quality.
1 . A method of determining a good quality of an electrode ink configured to include a plurality of catalyst supports and a plurality of ionomers, and configured to form a catalyst layer of a fuel cell,
wherein, in an inner portion of the electrode ink, by adsorption of the ionomers around the catalyst supports, primary aggregate that does not aggregate with others of the catalyst supports is formed, while on the other hand, by aggregation of the catalyst supports themselves without the ionomers around the catalyst supports, secondary aggregate is formed,
the method of determining the good quality of the electrode ink comprising:
detecting elastic modulus of the electrode ink;
estimating a state of the primary aggregate and the secondary aggregate within the electrode ink based on the detected elastic modulus; and
as the primary aggregate becomes more plentifully contained relative to the secondary aggregate, the more it is determined that the electrode ink is a good-quality product.
2 . The method according to claim 1 , further comprising:
detecting viscosity of the electrode ink along with the elastic modulus;
calculating loss tangent using the detected elastic modulus and viscosity, and estimating the state of the primary aggregate and the secondary aggregate within the electrode ink based on the calculated loss tangent.
3 . The method according to claim 2 , further comprising
detecting the elastic modulus and the viscosity with a rotary rheometer.