3 25 A Fuel Cell Was Tested In The Laboratory And Yielded The Following Open Circuit Voltage 0 9 V Internal Resista 1 (27.98 KiB) Viewed 37 times
3 25 A Fuel Cell Was Tested In The Laboratory And Yielded The Following Open Circuit Voltage 0 9 V Internal Resista 2 (27.98 KiB) Viewed 37 times
3. [25%] A fuel cell was tested in the laboratory and yielded the following: Open-circuit voltage 0.9 V Internal resistance 0.015 Voltage (I-1 A) 0.72 V Voltage (1-10 A) 0.45 V Thermodynamic analysis indicates that the reversible voltage of the fuel cell is 1.2 V and that the enthalpy change of the reaction is 1.26 times the reaction free energy change. Two electrons circulate in the load per molecule of fuel. Assume the Tafel Equation is valid. The internal resistance given above is the slope of the straight-line portion of the i-V curve characteristic of the cell. (a) Evaluate the inner current/fuel cross over overvoltage, in V. (b) Evaluate the Ohmic overvoltages at /- 1 A and /= 10 A. (c) Evaluate the activation overvoltages at /= 1 A and 1= 10 A. (d) If Tafel equation can be expressed in a form of AVact - A+B In I, find the two coefficients A and B. (e) What is the power the cell delivers to a load when the current is 5 A?
Join a community of subject matter experts. Register for FREE to view solutions, replies, and use search function. Request answer by replying!