is there any equation to get the relationship between hydrogen comsumption rate and output voltage of a fuel cell

Question

i am wondering if there any equation to get the relationship between hydrogen consumption rate and output voltage of a fuel cell. for example : To get like 12 volts, how much hydrogen need to be supplied..

Answer 1

You should be able to find equations like that in a spacecraft systems engineering book.  Such a book should have a chapter on design of spacecraft power systems, including H₂/O₂ fuel cells.  Are you a student at a college with a major engineering school?  If so, the mechanical, chemical, and aerospace engineering libraries are a good place to find such books.

 

I just looked at one particular old book (1995):  Spacecraft Systems Engineering, by Peter Fortescue and John Stark.  The section on fuel cells has an equation for the voltage E_r at the terminals of an ideal H₂/O₂ fuel cell.

 

E_r = -ΔG / nF

 

ΔG = change in Gibbs free energy during the reaction = -237.2 kJ/mol at 25°C for the H₂/O₂ reaction 

n = number of electrons transferred in the reaction = 2 electrons per mole of water formed

F = A₀e

A₀ = Avogadro's number

e = magnitude of electron charge

 

This book does not get into too much detail.  I suggest you start by visiting a library that has a good collection spacecraft systems design books, and find a book with more detail.