Living microbial cement supercapacitors with reactivatable energy storage | Hacker News Reader

Living microbial cement supercapacitors with reactivatable energy storage

cell.com

88 pointsPaulHoule44 comments

Morpheus steps forward, coat brushing his legs like a pendulum.

He lifts a slab of rough, gray cement from a conjured table, its weight palpable in his hand.

Morpheus: “For millennia, cement has been regarded as inert structural material. Here, we challenge this long-standing perception by transforming cement into a ‘living’ energy device, ... through the development of a microbial cement supercapacitor.”

He sets it down with a resonant thud. Immediately, thin blue veins of light snake across its surface, the fluorescence of a living substrate.

Neo takes a half-step closer, eyes narrowing.

Neo: “You’re saying… walls could think?”

Morpheus circles him, slow, deliberate, his voice low and electric.

Morpheus: “Not think. Store. The very foundations of their prisons becoming batteries. Imagine—every tower in the Matrix, a living entity, feeding the machine’s hunger, while we believed them empty stone.”

The slab flares green, light coursing outward in a pulse. Neo instinctively shifts back, fists tightening.

Neo: “And you want me to believe we can turn their biopower into ours?”

Morpheus stops directly in front of him, their eyes locked. A faint smile.

Morpheus: “I don’t want you to believe it, Neo. I want you to feel it.”

Neo reaches, fingers splayed, toward the slab.

It dissolves into motes of red light, scattering into the infinite.

Neo: "Woah."

I was wondering if it makes the cement weaker, but it looks like the bacteria actually make it stronger.

> At 3 days, EAM-containing samples exhibit increased overall porosity compared to the control, indicating an initial disruption in matrix densification. However, by 28 days, this effect diminishes, suggesting that hydration and subsequent microstructural stabilization mitigate the early porosity increase. Further analysis of pore size distribution (Figure 2F) shows that EAM incorporation leads to an increase in middle and large capillary mesopores, whereas coarse mesopores decrease, indicating a shift in the microstructure toward a more refined network. Despite these microstructural modifications, compressive strength measurements (Figure 2G) show that EAM incorporation does not compromise the structural integrity of cement. At 3 days, samples with higher EAM content exhibit a reduction in strength. However, by 28 days, strength recovery is observed, and EAM-containing samples exhibit a slight improvement compared to the control. This enhancement may be attributed to the formation of additional calcium carbonate, which contributes to matrix densification and mechanical reinforcement.

> Our findings establish a new paradigm for bio-integrated, cement-based energy materials, paving the way for energy-autonomous infrastructure.

"You see what I did there? Paving. Get it?"

Right. Now unleash the academic peer review puns. They've given permission.

Modern concrete is ubiquitously reinforced with steel. I wonder what effect on oxidation (modern concrete's primary failure mode) this would have?

Steel would presumably cause dead shorts, which are a even more direct failure mode.

What’s the downside here? Lithium ion batteries have an energy density of 150-350 Wh/kg, so this is firmly at the bottom of that range.

Naive, back of the napkin is 446 kWh / m^3. There’s a lot of content out there!

I haven't read the paper in detail yet but the easiest way to cheat is to calculate the density of a single layer, "capacitor plate" or surface or whatever it is that the microbes are living on and consider the "structural" cement as not counting towards the density calculation because theoretically speaking, there could be a manufacturing method to make a cement that creates the promised surface area even though such a process would be completely impractical to commercialise.

"Sorry the power is out - the concrete got sick".

And ensuring electrode integrity is probably quite fiddly during construction and maintenance is presumably also fiddly.

Exciting for a proof of concept. Hope to see this further developed!

Always exciting to see people taking steps towards a wetware future, one of my favourite scifi horror tropes. Bring on the flesh!

>Achieves 178.7 Wh/kg energy density and 8.3 kW/kg power density

Can someone explain this to me please. What is “energy” measuring here? How is it different from power?

W = Watt. h = hour. One kg supply one watt of power for 178.7 hours (without considering other factors). Power is how much energy can it supply at a moment. Up to 8.3 kW instantaneous.

Does it follow that 8.3 kW instance lasts .1787th of an hour?

No, it would last .0215th of an hour or ~77.5 seconds.

Is it a base 60 thing, how did you do the math?

There's no base 60 involved, it's the energy available divided by the power delivered:

178.8 Watt hours / 8300 Watts ≈ 0.0215 hours

Thanks, Not sure where my math went wrong.

Hours to seconds conversion probably, the number 60 plays a role there. (Albeit not base 60 but mod 60, but I'm not firm enough in the math to rule out that there is some correspondence between the concepts)

Energy is how much work you can do. Power is how fast you can do it. When you express these in terms of densities, it’s how much energy a certain quantity of material can store, and how quickly that energy can be released from a certain quantity of material.

If you short out a AA battery, it will get warm for a little while. If you short out a 14500 Li-ion battery (which is the same size and comparable energy density), you might get a small explosion as it dumps its energy very quickly.

Power is the time derivative of energy.

yeah I'm sure that someone who doesn't understand the difference between power and energy definitely understands derivatives...

you somehow managed to be perfectly unhelpful, condescending and insecure at the same time?

presumably energy is how much it can store and power is how fast you can get it out?

"Well that Sounds Like Slavery With Extra Steps"

You've got plenty of bacteria working for you (and sometimes against you) in your gut. Microbe-enhanced cement is a significant research topic. And the most plausible route to a chemical "factory factory" that space colonists would need to make middle and top-of-pyramid chemicals is a synthetic biology platform where you could make bespoke bacteria and yeasts that could make just about anything for you.

I’m not sure if I’m joking or not, but the difference between your two examples is one of them is a choice and the other is not. Maybe we’re going to enter a new era of microorganism ethics (or morality?).

Microorganisms get interesting because they’re simple enough that we can see all the parts involved, but complex enough that we can see what looks like intentionality in their actions. We consider them Alive, but we also know all the mechanisms making them seem that way - there’s nowhere for the ghost to hide. They’re a fascinating case for ethics, especially since there’s effectively no way we could operate in this world without both relying on them and killing them in droves, because they’re also parts of the mechanism almost anywhere we look at biology. Hell, human cells are outnumbered 10:1 - by number, we’re outvoted.

Yeah I think if ethics are involved it has to be based on intentions and hence choice. Accidentally stepping on a few million microorganisms is probably ethically ok. Building your civilization in the “enslavement” of gazzilions of microorganisms might be more ethically discussion worthy. I do wonder how plants are different than microorganisms if at all since obviously we farm and eat them.

With microorganisms it’s particularly interesting because the time and space scales are so different there’s no coherent narrative between humans and bacteria - it’d be like a species of sentient space nebulas seeding a promising planet with proto-humans so we’d eventually plant fruit trees there or something. In one sense, yes, if you were one of the eventual resulting humans, you’re the result of an alien species enslaving humans to do their bidding, but you’re living your entire life just generally doing what you’d do as a human totally unaware of your apparent enslavement and with no apparent restrictions on your movement or decision-space. I’m not an ethicist - anything that doesn’t involve the full consent of all parties gives me pause, but I’m not quite sure what the conversation there looks like.

Well these humans would be totally ignorant of what’s going on but that I think would be besides the point because the space nebula would know what they’re doing!

And then one of the space nebula decided to take the form of their creation. Thus it came down to earth to walk amongst them humans as one of them and this is how linus became benevolent dictator for life.

Plants are orders of magnitude more complex than microorganisms and we "intentionally kill/enslave" them in huge amounts. If you think it's ethically questionable to "enslave" microorganisms, what do you think of eating plant based food, and how do you propose we live?

It’s the fact that there’s no good answer that makes it a dilemma

The fact that you don't have an alternative other than suicide removes much of the dilemma..

No, that’s precisely what creates the dilemma - do you have a moral or ethical right to take the life of a sentient being to save your own? Do you have a right to do so repeatedly over time? What makes your life worth more than those you’re taking?

How do the microbes in someone’s gut have a choice in the matter?

I should have been more clear, I meant our choice as in we did not choose or coerce them to be in our gut but we would have chosen to use them in our civilization’s infrastructure.

No more so than brewing beer with yeast or fermenting wine or growing crops.

Yeah that may be true, but how do we feel about using actual brain tissues to train AI like:

https://corticallabs.com

The fact that brain organelles start spontaneously firing in synchronized patterns when they reach a certain size is enough to give me serious pause about anything trying to use brain tissue. We don’t quite know what consciousness is, but we know what it looks like from the outside.

Oh my. Shot from the hip: Not good.

Don't anthropomorphize microbes. They hate it when you do that.

Eek barba dirkle, someone got laid in college

Wait til you learn where honey comes from

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