
Supercapacitors from Standard Bricks - tomcam
https://arstechnica.com/science/2020/08/how-to-turn-regular-bricks-into-electricity-storying-supercapacitors/
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Animats
_Energy density of 222 µWh cm−2_

As a battery, this is not useful.

A standard brick is 2Kg, volume 1300 cm^2, or 0.0015 Kg/cm^2. So that's
148,000 uWh/Kg, or 0.148 Wh/Kg.

That's not much. A lead-acid battery is 30 to 50 watt-hours / Kg. Existing
ultracapacitors have an energy density of 5 to 10 watt-hours / Kg. So this is
about 1/200th the energy density of a lead-acid battery, or 1/33 of an
ultracapacitor. Not bad for a first try. It may be possible to improve on the
material. Get the surface to volume ratio up.

But as a capacitor, it's quite good. Use this technology to replace ordinary
electrolytic capacitors in power supplies. Capacitors have been the weak point
in power supplies for a century. As an ordinary capacitor, it's 1.60F/cm^2 at
1.2V. Farad, not uF. That's very good compared to ordinary electrolytics. The
main problem is the low current - 0.5mA/cm^2. That has to be increased for
this to be useful as a filter cap. That's mostly a connection problem -
getting enough conductor near the capacitor component.

~~~
elil17
It’s also not a very good energy per unit cost, at about $600 per kWh
(assuming $0.50 per brick, which is fairly typical for bulk brick orders).
Meanwhile, Tesla is targeting a supercapacitor cost of $150/kWh.

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limomium
Yeah but if you're building a house, you need the bricks anyway. Why not make
your walls a battery while at it?

~~~
war1025
Are there still places where brick construction is common?

Any semi-modern building I've seen in my area is wood-frame with maybe a
decorative brick facade on part of a wall.

I can't imagine the cost of building a brick house makes any financial sense
when compared to more modern construction methods.

Am I wrong in this?

~~~
SEJeff
Many parts of the US prefer the aesthetics of brick. It isn't about the cost.

~~~
war1025
> Many parts of the US prefer the aesthetics of brick

At least around here, if you want the aesthetic, you go for wood frame with
brick facade.

How does brick work for modern wiring, plumbing, insulation needs? Most of
that stuff is traditionally routed at least partially through load bearing
walls.

~~~
serf
>How does brick work for modern wiring, plumbing, insulation needs? Most of
that stuff is traditionally routed at least partially through load bearing
walls.

it's not much different other than the addition of a masonry drill bit.

in the case of very large plumbing, sometimes whole bricks are left out and
the area filled/finished with a conrete mixture and left to set around the
pipe.

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moh_maya
A well explained article from Ars Technica discussing this. As ever, the
comments are at least as insightful and interesting as the article.

[https://arstechnica.com/science/2020/08/how-to-turn-
regular-...](https://arstechnica.com/science/2020/08/how-to-turn-regular-
bricks-into-electricity-storying-supercapacitors/)

~~~
dang
Ok, we'll change to that from
[https://www.nature.com/articles/s41467-020-17708-1](https://www.nature.com/articles/s41467-020-17708-1).
Thanks!

For specialized papers it's generally better to submit the highest-quality
third party description and link to the paper in the comments. Exceptions
would be fields like computing where the bulk of the audience is able to read
the specialized paper without much trouble.

------
SEJeff
I wonder if this could be used with the bricks used from expelled tunnel
material from the Boring Company. It would dovetail nicely into the rest of
Musk Enterprises.

[https://electrek.co/2018/07/13/elon-musk-boring-company-
bric...](https://electrek.co/2018/07/13/elon-musk-boring-company-bricks-dirt-
tunnels/)

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sp332
This is a great result from some off-the-shelf materials (uh, and a vacuum
deposition chamber I guess). With some engineering for cheap manufacturing and
improved capacity, the modifications might at least pay for themselves.

~~~
hinkley
Maxwell was essentially doing this with activated charcoal, weren't they?
While it might be surprising to many of us, I doubt it's that surprising to
anyone working, or even investing, in this problem domain.

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mrfusion
I’m confused what the dialectic medium separating the two charged elements is?

~~~
moftz
Figure 5b has a description that reads "Cyclic voltammograms for symmetric
supercapacitors using 1 M H2SO4 aqueous electrolyte and poly(vinyl
alcohol)/H2SO4 gel electrolyte". Looks like you can either submerge the bricks
in a solution or have a gel layer between them to produce the actual capacitor
structure.

~~~
ryanmarsh
They must be in sulfuric acid? So we’re not building houses out of this any
time soon.

~~~
moftz
I don't think this would be for building homes, it would just be a potentially
cheap way to build large capacitor banks for homes.

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woodandsteel
Question: why is this called a supercapacitor, rather than just a standard
one?

~~~
projektfu
They have about 4-8 orders of magnitude more capacitance per unit area than
film or typical electrolytic capacitors.

