Nikola Corporation (NKLA)

[srm4u]

A fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen[1]) into electricity through a pair of redox reactions[2] Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen (usually from air) to sustain the chemical reaction, whereas in a battery the chemical energy usually comes from metals and their ions or oxides[3] that are commonly already present in the battery, except in flow batteries. Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied.

is this what you're saying?....if it is it's already been in use....
https://en.wikipedia.org/wiki/Fuel_cell

Summary: Space Applications of Hydrogen and Fuel Cells
The space shuttle docks with the International Space Station.The space shuttle docks with the International Space Station in orbit. Credit: NASAFor decades, NASA has relied upon hydrogen gas as rocket fuel to deliver crew and cargo to space. With the Centaur, Apollo and space shuttle vehicles, NASA has developed extensive experience in the safe and effective handling of hydrogen. For example, the rocket engines of each shuttle flight burn about 500,000 gallons of cold liquid hydrogen with another 239,000 gallons depleted by storage boil off and transfer operations.
https://www.nasa.gov/topics/technology/hydrogen/hydrogen_2009.html

Alstoms hydrogen fuel cell train wins 2018 GreenTec Mobility Award
Alstoms Coradia iLint, the worlds first hydrogen fuel cell powered regional train, has won the GreenTec Award 2018 in the category Mobility by Schaeffler. Today Alstom was officially presented with the award at its largest production site, located in Salzgitter, Germany, during an advance award ceremony ahead of the GreenTec Awards gala to be held in Munich on May 13th.
https://www.alstom.com/press-releases-news/2018/5/alstoms-hydrogen-fuel-cell-train-wins-2018-greentec-mobility-award

Ballard Signs Supply Agreement With Norled for Fuel Cell Modules to Power Ferry in Norway
The Administration Director of Norwegian Public Roads, Terje Moe Gustavsen said, "Hydrogen will be the last piece in order to get zero-emissions in the ferry sector. Hydrogen is the solution where electric operation alone is not possible."
https://markets.businessinsider.com/news/stocks/ballard-signs-supply-agreement-with-norled-for-fuel-cell-modules-to-power-ferry-in-norway-1028094555#