Method for optimizing diffusion media with spatially varying mass transport resistance

A method for optimizing a fuel cell diffusion media having a spatially varying mass transport resistance, the method comprising the steps of:

• a) identifying i) a plurality of operating conditions for a fuel cell in a vehicle, the plurality of operating conditions including a baseline operating condition, ii) at least one fuel cell variable correlated to fuel cell performance, and iii) a desired range of the at least one fuel cell variable;
• b) determining at least one baseline variable profile for the fuel cell;
• c) providing a first-pass D/Deff profile for the fuel cell diffusion media;
• d) applying the first-pass D/Deff profile to a computational model of the fuel cell having the baseline variable profile;
• e) calculating at least one first-pass variable profile resulting from the application of the first-pass D/Deff profile to the computational model;
• f) comparing the first-pass variable profile to the desired range of the variable,
• g) refining the first-pass D/Deff profile if the first-pass variable is not within the desired range and repeating the steps d) to f) until the first-pass variable profile is within the desired range, wherein a second-pass D/Deff profile is provided;
• h) calculating a plurality of second-pass variable profiles with the second-pass D/Deff profile;
• i) comparing a relative performance of the fuel cell with the second-pass variable profile and the first-pass variable profile;
• j) refining the first-pass D/Deff profile if the performance of the fuel cell with the second-pass variable profile is less desirable than the performance of the fuel cell with the first-pass variable profile, and repeating the steps d) to i) until the fuel cell having the second-pass variable profile has a superior fuel cell performance, wherein an effective D/Deff profile for the fuel cell diffusion media is provided.

A method for optimizing a fuel cell diffusion media having a spatially varying mass transport resistance, the method comprising the steps of:

• a) identifying i) a plurality of operating conditions for a fuel cell in a vehicle, the plurality of operating conditions including a baseline operating condition, ii) at least one fuel cell variable correlated to fuel cell performance, and iii) a desired range of the at least one fuel cell variable;
• b) preparing the fuel cell having a uniform D/Deff profile under the baseline operation condition;
• c) measuring at least one baseline variable profile of the fuel cell;
• d) providing a first-pass D/Deff profile for the fuel cell diffusion media;
• e) applying the first-pass D/Deff profile to a computational model of the fuel cell having the baseline variable profile;
• f) calculating at least one first-pass variable profile resulting from the application of the first-pass D/Deff profile to the computational model;
• g) comparing the first-pass variable profile to the desired range of the variable
• h) refining the first-pass variable if the first-pass variable is not within the desired range and repeating the steps d) to g) until the first-pass variable profile is within the desired range, wherein a second-pass D/Deff profile is provided;
• i) preparing the fuel cell having the second-pass D/Deff profile;
• j) measuring a plurality of second-pass variable profiles of the fuel cell having the second-pass D/Deff profile under the plurality of operating conditions;
• k) comparing a relative performance of the fuel cell with the second-pass variable profile and the first-pass variable profile;
• l) refining the second-pass variable profile if the performance of the fuel cell with the second-pass variable profile is less desirable than the performance of the fuel cell with the baseline variable profile, and repeating steps d) to k) until the fuel cell having the second-pass variable profile ahs a superior performance, wherein an effective D/Deff profile for the fuel cell diffusion media is provided.