
Making high-performance batteries from junkyard scraps - Jerry2
https://news.vanderbilt.edu/2016/11/02/making-high-performance-batteries-from-junkyard-scraps/
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abakker
So, this would involve anodizing the steel in Nitric Acid to make a suitable
anodized surface (that wasn't just rust). I'm not sure what the anodizing bath
needs to be for brass. I wonder what they use?

This sounds like a great thing to release an instructable for. I'd be happy to
give some home chemistry and construction a try to build a big battery.
However, I question whether all this can really be done _safely_ with "home
chemicals". Many home chemicals are hardly safe and have some serious
potential for harm if you find yourself breathing fumes, burning, heating,
boiling, or handling them. I wonder at potassium hydroxide in sufficient
concentration to be a useful electrolyte. Anything >2% is considered caustic.

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cr0sh
I think the biggest problem with this, based on the paper - is the fact that
to anodize the steel, you have to heat it to 600+ degrees F for an hour, in an
argon or hydrogen atmosphere.

How the heck you do that "at home" won't be easy. Maybe take an old oven
(outdoors), stick it on the cleaning cycle, then put the steel electrodes in a
sealed pyrex container (?) filled with argon/hydrogen?

Maybe fill a steel pipe capped off with hydrogen, then heat that in the oven
(where the inner surface becomes the electrode) - that might actually work ok
(if a bit dangerous). Though how to seal it properly to prevent the hydrogen
from leaking out might be a challenge.

If the pipe idea could be worked out - then a series of brass rods or plates
could be used suspended (and electrically insulated) from the steel pipe, to
form the battery electrodes (similar to how a regular alkaline or carbon-zinc
cell is constructed).

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jakeogh
Hydrogen is a pain to work with. Other than being explosive in air, it leaks
unless the seal is near perfect. On the flip side, it's easy to obtain via
electrolysis. If argon is acceptable it would be much easier to work with. The
pdf reads like a mixture was used. I have done some work @ 1300C where we
needed an inert atmosphere, so we plumbed an argon tank to the furnace and ran
it at a slight positive pressure.

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prefect42
This has the potential (pun intended) to be a big deal in wild world of
battery tech. BUT I'd like to see the next phase if, or more hopefully when,
they can demonstrate a battery with enough capacity for a home. And provide
DIY instructions on how to build. Still very exciting nonetheless.

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dyne
More information:

[http://pubs.acs.org/doi/suppl/10.1021/acsenergylett.6b00295/...](http://pubs.acs.org/doi/suppl/10.1021/acsenergylett.6b00295/suppl_file/nz6b00295_si_001.pdf)

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dgelks
Interesting discovery, however the energy density of such a battery would mean
it couldn't ever be used to replace current lithium cells due to weight/space
constraints. Might have a niche somewhere if gets to commercialisation stage?

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mikeash
Stationary storage doesn't care about weight and doesn't care a whole lot
about space, so it sounds like a decent fit. Grid storage is becoming very
important and useful as inconsistent renewable power (wind and solar) becomes
cheaper and more common.

