question archive 3) Your company has just purchased a new Alkaline Fuel Cell (AFC; not a stack) to help power its warehouse operations
3) Your company has just purchased a new Alkaline Fuel Cell (AFC; not a stack) to help power its warehouse operations
Subject:ChemistryPrice: Bought3
3) Your company has just purchased a new Alkaline Fuel Cell (AFC; not a stack) to help power its warehouse operations. Before installing the fuel cell, your boss has asked your team to do some analysis on the cell. One of your team's tasks is to characterise the reaction surface area. Your testing indicates that when the cell is generating 1.5 A/cm2, the activation overpotential is large (a value of 0.4 V). The cell operates at 470 K, the transfer coefficient has been estimated to equal 0.5, and you know that the exchange current density for a smooth cathode would be 2 × 10-9 A/cm2.
a. Calculate the real cathode area relative to the area of a smooth electrode. (2 marks)
b. Your boss is unhappy with the large activation overpotential of the cell. Identify one potential design change that you could make to the cell to reduce the activation overpotential, and provide a calculation that shows the improvement (assume the manufacturer will take back the fuel cell, make the change and then return it to you). (2 marks)
