The Science Behind Fuel Cells - How They Powered Spacecraft, Cars And Sometimes Phones

For the last 50 years every crewed mission to space launched by the US has been powered by fuel cells, these directly convert the fuel's chemical energy into electrical power without an intermediate mechanical step. So, let's try and explain how they work, and how there are many types of fuel cell technology which have their own advantages and disadvantages.

[jessecarozza]

And in 15 minutes, Scott summarizes the thesis chapter that took me six months to write. :p

[theCodyReeder]

I have a 1.4kw hydrogen fuel cell I plan to use at ChickenHole Base. 😊

[hatman]

10:08

I work on KC-135 jet engines for a living.

Occassionally I see something that shocks me... In this case, all the hardware in this photo, such as the style of canon plugs, excessive amounts of safety wire, etc, looks insanely familiar... Because it's exactly the sort of stuff my jet's made out of. I occassionally get these sobering reminders just how OLD my jet it.

Similarly, I once saw videos of the interiors of B-17s and DC-4s... I swear to god, we use identical light fixtures and seat racks as these WW2 planes.

[markschenher]

I worked for the company that made the Apollo and Shuttle fuel cells
You did an excellent job describing them


Sadly this small division was spun off after the grounding of the Shuttle and soon thereafter the new company went bankrupt
A foreign company now make stationary fuel cells at the factory

[pentagramprime]

How many beers would Scott need to accurately recreate the landing of the “KABOOM CASE” in KSP?

[Hiis]

The lack of fuel cells on the Dragon isn't that surprising given that battery power density has increased dramatically in fifty years, that Elon Musk runs a company that makes batteries, and that the spacecraft doesn't use hydrogen for other purposes so incorporating it is not incremental in nature.

[shrikedecil]

A battery is basically a fuel cell and a fuel tank sealed up together and intermingled. This is handy, concise, and pretty accurate. All the mechanical shenanigans, temperature optimization, fuel-purity requirements - all of it - is the effort to "grow" the fuel tank aspect *without* growing the (complex, expensive, heavy) electrode/electrolyte interface part. (Which is often amazing looking at how much extra gear that's taking!) The fussing with "what is the electrolyte" and "what is the anode/cathode" are all the precise same problems of batteries (although fuel cells often involve more dinking with gases).

[hydrochloricacid]

We covered fuel cells and batteries in last year's chemistry lesson on reduction/oxidation. Thank you for reminding me that I've already forgotten about its contents.

[samiraperi]

"Astronaut badassery" must be a thick book.

[vikkimcdonough]

1:48 - Note that this happens even without a load connected, because even dilute sulphuric acid corrodes lead and lead dioxide (albeit slowly), evolving hydrogen and oxygen in the process; this is why lead-acid batteries have such a short storage life.

[krzysztofczoczynski]

I've got a kind of Pavlov response with automatic "it's gonna be a good video" when I hear "Hullo"

[edding]

Excellent video. I have worked on solid oxide fuel cells when I was doing by bachelors degree. The most common problem with the SOFC is the adherence of carbon on the anode surface.

[Niklas]

Just did my Bachelor's thesis on Fuel Cells; I gotta say that you're spot on with your vid! :)

[StYxXx]

Fuel cells are also used to power and heat homes using natural gas. At least in Europe and especially Asia they're commercially available. There are several types in use, like solid oxide fuel cells and proton-exchange membrane fuel cells.

[tylercragun]

Always fun to log in to youtube and find a new Scott Manly Video Fresh off the Press!

[paulmckenzie]

7:00 chef boyardee cooking up a spicy fuel cell

[WobblycogsUk]

Many years ago now I was a chemist doing research into solid oxide fuel cells, I've never heard such a concise and well put together overview of fuel cells as presented here, good job.

[stanburton]

A bit over 15 years ago, i worked on a research project that was run by Reliant Resources, (and of course funded by the DOE) that was intended to be distributed power generation fuelled by natural gas that was steam cracked and fed to a PEM fuel cell array. Thisxwas intended to be a device aboutvthe size of a large outdoor AC condensing unit consisting of a cracking unit, PEM array, and inverters. Each subsystem was contracted out to different suppliers, our group was in charge of the PEM array, as well as final integration. The cracker was a majorcstumbling block, i do not believe the contractor had any intention of delivering a functional product, mercaptans were a problem as the sulphur poisoned the Nafion PEM membranes. Water was necessary to keep the Nafion membranes moist at all times and water purity was an issue. The cells had a limited lifetime (but we were working on that, it was a materials issue that i was working with the metallurgists to help solve due to my background with high performance ceramics and plastic seals) we were able to generate 21KW out of 6 PEM cells, and that was with 30% inverter losses. But the cracker delays as well as the political issues of the time ended up killing the project.

[cheaterman]

Always a pleasure to learn new things with you, Scott. Thanks! I didn't realize there were so many planned applications for fuel cells outside of aerospace!

[RCAvhstape]

Back when I used to use the Orbiter Spaceflight Simulator there was an addon vehicle called the "Dragonfly" that was basically a tug for moving cargo and other modules around a space station. Whoever created it had built into it a detailed model of fuel cells, and I remember that operating the vehicle was complicated due to the complex sequence you had to go through the start up and manage the fuel cells.