I cant say I know much about fuel cells. So when I looked at a fuel cell I wondered. Since the membranes are stacked. Have the system a similar problem of efficiency as stacked peltier elements?
If so then it might be an idea to use many small thin fuel cell units. Look at https://www.greenoptimistic.com/smallest-hydrogen-fuel-cell-20090113/ Something like that.
What if you can make a small fuel cell unit very efficient and scale that thousands of times. Could this large cluster power something more than electronics?
I mean to charge the electric car battery on the go or at stops.