Hydrogen & Fuel Cells | Reactions | Chemistry | FuseSchool

Hydrogen & Fuel Cells | Reactions | Chemistry | FuseSchool

In this video, you will learn about how we are trying to design a way to power vehicles of the future on hydrogen, oxygen and sunlight.

In order to obtain energy for the vehicle from hydrogen (that is stored as a fuel cell for motor vehicles), we need to rejoin the hydrogen with oxygen. This is done most efficiently in what is called a fuel cell.

In an ordinary electric cell, a metal, say zinc, ionizes at one electrode, the anode, giving off two electrons. The electrons are pushed around the circuit carrying energy, to, for example, a motor and absorbed by metal ions of a less reactive metal, say copper. The circuit is completed by the movement of metal ions through the solution.

In a fuel cell, the reactants are gases instead of metals. Hydrogen gives its electrons. The electrons flow round, driving the motor, and arrive at the cathode where they are recombined with hydrogen in the presence of the reactive gas oxygen, which provides the driving energy to form water again. The electrodes can be made of porous carbon coated with a catalyst, such as platinum or nickel.

The advantage of combining a fuel and oxygen in a cell is that you can in theory convert most of the chemical energy to electricity whereas burning them, as happens in the internal combustion engine of a car, has a maximum efficiency of about 50% and in practice only about 25% of the chemical energy does useful work in driving the engine - the rest comes out as waste heat.

There are two major problems to using hydrogen fuel cells in vehicles.

Firstly, where do you get the hydrogen? Currently most industrial hydrogen is derived from methane and the carbon is rejected as carbon dioxide, thus adding to the greenhouse effect. The hope is that we can learn to mimic photosynthesis by using sunlight to split water molecules apart, giving us a clean and simple source of hydrogen. Currently this is achieved by using photovoltaic cells to generate electricity, which then electrolyses water, forming hydrogen and oxygen. To take the analogy further, the hydrogen is transported to the fuel cell, like biomass passing along a food chain, and the oxygen, which we tend to take for granted, is vented to the atmosphere. The fuel cell then gets its oxygen from the atmosphere, just like in respiration. The energy is stored whilst the hydrogen and oxygen are kept apart.

The other problem is how to store and transport the hydrogen gas once you've got it. It's extremely difficult to liquefy and rather dangerous if kept as a gas under pressure, particularly if the vehicle crashes. Research is therefore focusing on hydrides, compounds of elements with hydrogen, which are solid or liquid at room temperature and which give out their hydrogen reversibly and without too much energy input. This allows hydrogen to be pumped in, reacting to form the hydride and, then, on the journey, the hydrogen is given off to be used in the fuel cell to drive the vehicle. For example, ammonia borane, a solid at room temperature with the same structure of ethane, gives up its hydrogen on heating.

However, it will probably be more energy efficient to run the cars on batteries which are charged from green electricity.

Fuel cells generate electricity from the reaction between a fuel and oxygen. Using them on vehicles means that we need to develop a way of storing hydrogen, which is difficult. It is more likely that vehicles of the future will be powered by batteries.

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[zoomerenhd]

2:47
please keep in mind that methane is also a greenhouse gas, so it is switching one greenhouse gas for another.

[hazerthegamer]

whenever their is a chemistry problem i search my question your video is on top and the first thing i do is a 👍 cuz i have subscribed already

[tonniej]

'Storing hydrogen = difficult, thus cars will run on batteries'. Great analytic conclusion. Going to the moon was an easy job, if it had it been difficult it would have never happened. Off course profit driven society goes for the easy option to excavate entire islands, no even countries (Republic of Madagascar), in search of precious resources such as Nickel / Cobalt / Lithium to store energy in an efficient way. Because yes, things need to be easy to do so.

[chaerunraudhatulislam]

when a conductivity of material is high, we use a electrolysis method to break a bond of oxygen and hydrogen. however, then a conductivity of material is low, we use a photocatalyst .

[chandrashekharkotekar]

What if we use Hydrogen fuel cells to power our homes instead of cars? We usually get water through pipe, we can generate electricity using few solar panels. Using this electricity we can create Hydrogen for fuel cells and generate much more electricity needed for entire house. (we can perhaps use solar power itself to generate electricity for entire home)

[jefftormey]

It’s crazy how he casually writes off the ability to store hydrogen safely.

[vishank]

This is beautiful on multiple levels! Really appreciate your work sir.

[abstractexchange]

hydrogen is the only right variant for future. No other variant ! But we are developing approach, which is not exact now. There must be 2 waves for hydrogen : 1/BUILD HYDROGEN PRODUCTION FACTORIES ON SITES OF RENEWABLE ENERGY STATIONS. 2/ SMALL CARS NEED TO LOAD HYDROGEN BY EXCHANGING WHOLE COMPRESSED HYDROGEN BALLOONS.
We are wrong because we do not firstly build enough hydrogen production factories on sites of renewable energy stations. We are wrong because we are trying to build network of hydrogen loading stations, which are COMPLEX AND EXPENSIVE.
We must change our approach. We should use hydrogen as energy storage method for renewable energy stations first. Then we should load hydrogen for usual cars by exchanging whole standard sized compressed hydrogen gas balloons. So It is very simple and not expensive to make the global net of hydrogen supplying stations. Any normal mini shops can be a hydrogen supplying point by storing standard sized compressed hydrogen gas balloons. We do not have to use liquid hydrogen, which is difficult to collect. But we can use compressed hydrogen gas, which is not so much different in weight by comparison with liquid hydrogen. Hydrogen is the best solution of energy storage for all energy stations now, for example, for nuclear energy stations, for renewable energy stations. Just install ready hydrogen production modules, and install independent hydrogen fuel cell modules in adjacent areas. Use compressed hydrogen gas at first time instead of liquid hydrogen.
And the last thing to notice is that, hydrogen is not more dangerous than other gases and petrol. Hydrogen has big energy storage capacity, but when burning hydrogen in accidents, IT DOES NOT CREATE ACOUSTIC DESTRUCTING WAVE TO ENVIRONMENTS. It means that hydrogen burning is less destructive than gasoline burning.

[parthikshaji]

amazing video ....i am sure that this channel will become one of the most popular youtube learning channels...thank you so much

[apexpowerconceptsdusolindu]

It'll be really funny to watch this video 10 years from now. Energy density and potential gains in round trip efficiencies will become hallmark of the mobility industry within the world that values sustainability - which is only possible using fuel cells/Hydrogen energy.

[nekogh]

amazing !! pls continue making videos like this

[linuxd]

Cars will be electric.

Large shipping trucks and heavy machinery will be a hydrogen/electric hybrid

(Mostly electric clean energy with the occasional or reduced exhaust of H2O through the means of hydrogen fuel)

[nilsmanuelgut]

Very good educational video.

I'm only unsatisfied about the example chosen for the greenhouse effect: methane is about 20 times more efficient of a greenhouse gas than carbon dioxide, therefore it is one of the rare cases where an exothermic reduction-oxidation reaction (i.e. Burning) actually reduces the greenhouse effect.

[jens]

Is the labelling correct at 2:06? Here's why I'm asking: (I am genuinely confused here, so please help someone...)
Firstly, the material that an electrode can be made of is stated to be carbon, which is labelled as the central part of the HFC. But that to me, doesn't seem to make sense, as an electrode, is a conductor where electrons enter to, or exit from, as part of travelling the alternate route to power an object. In the diagram, what is stated to be 'platinum/nickel', should be the electrode right? Furthermore, the central part is only shown to be a single object, and not two, which is the number of electrodes required for a current (along with an electrolyte) in such a setup. So that makes me think what is labelled as 'platinum/nickel' should be the electrodes. Also, (maybe this is too specific of a detail, idk) the wiring is shown to be surrounding the central part of the hsc, which would make me think more that the diagram might be wrong. (As i think it would make sense for the wiring to be after the anode, to allow for electrons to enter, and then conduct through the wire and vice versa for the cathode.) Plus, I'm a bit stuck on another thing, where I'm not sure what the layer that the protons move through (being the central object) would be called. Would it be an electrolyte? Or is it a proton exchange membrane, which is something I've seen in other stuff, or is it both? I'm not really sure on this and I don't even know if one involving the exchange membrane would even be another kind of hsc or something. Help, please...

[SteveWrightNZ]

The only reason to start turning water into hydrogen, is that your solar array has fully charged your batteries and is sitting there idle. In large systems, this is a lot of the time. That extra energy is genuinely free - you have it, you waste it, and you don't care that you had it - that's "free". Make hydrogen with it.

[beansbaby]

AP Environmental grind 😔 thanks for this

[sorendk]

What if you wanted to use hydrogen to power a ship? IE we take a 40 meter long catamaran with plenty of space on the deck for solar-panels + I believe you can buy sails who also have solar-cells in them. Would that be enough electricity to create Hydrogen to power 2 engines, pushing a pair of waterjet propulsion systems? Since you dont have to sail every day (unles crossing big oceans ofc) you could bask in the sun for a week, then travel until you run out of fuel and then repeat? What would be the biggest problem(s) with this idea you think? And aprox.. how much would you guess such a system (not including the ship, waterjets and engines, just the hydrogen system)) would cost?

[coolnessmortezchannel]

Lots of processing goes into hydrogen about the only thing I didn’t like about hydrogen was the explosive effects and batteries are near solid state level with out blowing up / you can use algae to produce hydrogen and make more efficient hydrogen stations/ with discharge water disposal and electrolysis in case you need more hydrogen or algae hydrogen overflow and balance it out with ultra capacitors

[vivian]

1:20 I am not exactly sure, but is Zinc suppose to be the cathode while Copper the anode? Thank you!

[mundymorningreport]

Nice video, are you aware that water can form highly diamagnetic molecules of multiple H2O sets? This can happen with just cavitation, but ionizing it first stimulates the formation. This type of water molecules becomes a gas above minus 158 deg C. at 5 atmospheres and standard (normal room temps) temps the diamagnetic forces making it a gas can be overcome and it will condense, releasing up to 6 times the amount of electricity as H2 fusing with O2. forming liquid water.... pretty cool huh? could save the future of fuel cells, don't you think? Party on Dudes, be good to each other.