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Researchers have developed a water-based battery to store solar and wind energy

news.stanford.edu

31–40 of 87 posts

Re: Researchers have developed a water-based battery to store solar and wind energy

#31
post #16

Earlier quoted context omitted.

The wrong circumstances required to catastrophically release all of that energy in an ICE car is pretty extreme, requiring the fuel to atomize and thoroughly mix with air. Otherwise you have a fire, not a bomb. Hydrogen by contrast just needs a spark and then it comes to strongly resemble a bomb. If your hydrogen is under pressure, then simple containment failure can be the “spark” required. Plus, gasoline is easy to…

Gasoline evaporates under most normal conditions when exposed to air. Fiel soaked rags have been known to spontaneously ignite in garages. I think what you're describing is the decades of safety advances we've had in ICE engine design that allow for safe fuel storage. I'm not trying to say that storing hydrogen is easy, I'm just saying that there's probably a significant amount of things we can do to bring the hazard…

I was only aware of oil (not gas) soaked rags spontaneously combusting

Re: Researchers have developed a water-based battery to store solar and wind energy

#32
post #27

>Cui estimated that, given the water-based battery’s expected lifespan, it would cost a penny to store enough electricity to power a 100-watt lightbulb for twelve hours. Oh dear, I hate university news "journalism" with a passion. For the life of me I cannot understand why they feel the need to dumb down parts of the content while other parts remain decidedly technical. Is it to have something that laymen can quote?…

"Excess electrons bubbled off as hydrogen gas, thus storing that energy for future use." Just wow.

"To mimic how a wind or solar source might feed power into the battery, the researchers attached a power source to the prototype."

Re: Researchers have developed a water-based battery to store solar and wind energy

#33
post #17

Earlier quoted context omitted.

Yes. Surface chemistry ("nanotechnology") seems to attract this sort of hype. "The prototype manganese-hydrogen battery, reported April 30 in Nature Energy, stands just three inches tall and generates a mere 20 milliwatt hours of electricity ... The researchers are confident they can scale up this table-top technology... " That is a really puny battery. It's 1/10th the energy capacity of a typical watch/hearing aid b…

Utility scale batteries optimize for energy/$, not energy density or weight etc. Your comparisons are totally irrelevant.

On that note, does anyone have any idea how it might compare to Peter Allen's open source Iron Battery project? I know the latter is in a very early stage, but maybe there is already a theoretical limit that can be predicted given the properties of manganese and iron.

http://peterallenlab.com/

https://www.youtube.com/channel/UC-t9a7XVoH9lDJzhUF2nyHQ

Re: Researchers have developed a water-based battery to store solar and wind energy

#34
post #29

Could someone ELI5 how the recharge cycle works? On charging it evolves H2 gas; how does that get put back on recharge? This is very much NOT explained by the paragraph, > The researchers did this by re-attaching their power source to the depleted prototype, this time with the goal of inducing the manganese dioxide particles clinging to the electrode to combine with water, replenishing the manganese sulfate salt. Onc…

This puzzled me also. Perhaps it's been kicked down the road as an engineering problem and we'd end up with a hydrogen extraction system which is responsible for that part. We'd probably need to feed protons back in though...

Re: Researchers have developed a water-based battery to store solar and wind energy

#35
post #6

Earlier quoted context omitted.

Well, any vehicles you park in your garage or in your driveway probably have a lot of stored potential energy that can be released catastrophically under the wrong circumstances too. (this goes for whether it's ICE or electric). The fact that we generally consider those safe to sleep next to is a testament to safety engineering (and possibly a bit of self delusion).

The wrong circumstances required to catastrophically release all of that energy in an ICE car is pretty extreme, requiring the fuel to atomize and thoroughly mix with air. Otherwise you have a fire, not a bomb. Hydrogen by contrast just needs a spark and then it comes to strongly resemble a bomb. If your hydrogen is under pressure, then simple containment failure can be the “spark” required. Plus, gasoline is easy to…

[deleted]

Re: Researchers have developed a water-based battery to store solar and wind energy

#36
post #16

Earlier quoted context omitted.

The wrong circumstances required to catastrophically release all of that energy in an ICE car is pretty extreme, requiring the fuel to atomize and thoroughly mix with air. Otherwise you have a fire, not a bomb. Hydrogen by contrast just needs a spark and then it comes to strongly resemble a bomb. If your hydrogen is under pressure, then simple containment failure can be the “spark” required. Plus, gasoline is easy to…

Gasoline evaporates under most normal conditions when exposed to air. Fiel soaked rags have been known to spontaneously ignite in garages. I think what you're describing is the decades of safety advances we've had in ICE engine design that allow for safe fuel storage. I'm not trying to say that storing hydrogen is easy, I'm just saying that there's probably a significant amount of things we can do to bring the hazard…

> spontaneously ignite

Yes, gasoline will burn easily can auto-ignite in common household conditions. I've had the "fun" of running for the garden hose after a roommate made a similar mistake with paper towels soaked with some type of cleaning solution and wiped up engine oil. Fortunately we were able to put out the fire with only minor damage (mostly smoke) to the garage.

However, that's only a fire that will burn[1] at a rate roughly proportional to hows quickly it can mix with oxygen (that can be very fast* in some situations). Getting gasoline to act like a bomb and release it's energy at once[2] requires fairly specific conditions.

[1] https://en.wikipedia.org/wiki/Deflagration

[2] https://en.wikipedia.org/wiki/Detonation

Re: Researchers have developed a water-based battery to store solar and wind energy

#39

> To mimic how a wind or solar source might feed power into the battery, the researchers attached a power source to the prototype. So, they charged the battery? Why doesn't the article just say that? Does the intended audience of the article not know what "charging a battery" is?

My guess is that the researchers designed their power source to mimic the behavior of solar and wind farms. The researchers were probably rather specific about these behaviors, but it was too verbose or technical for a news article. Some editor tried to summarize that part of the paper, and that editor failed which is how we got this ridiculous sentence.

Re: Researchers have developed a water-based battery to store solar and wind energy

#40
post #16

Earlier quoted context omitted.

Gasoline evaporates under most normal conditions when exposed to air. Fiel soaked rags have been known to spontaneously ignite in garages. I think what you're describing is the decades of safety advances we've had in ICE engine design that allow for safe fuel storage. I'm not trying to say that storing hydrogen is easy, I'm just saying that there's probably a significant amount of things we can do to bring the hazard…

I was only aware of oil (not gas) soaked rags spontaneously combusting

Yeah, I think that gasoline will just evaporate on a rag. the spontaneous combustion requires something like linseed oil that generates a lot of heat when drying(exothermic) and left alone on a rag.
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