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My story has a few androids and some beings that can manipulate electricity with their bio battery electric organs and I want these characters to have the ability to shoot powerful lasers, plasma projectiles etc but I am unsure how they could store that much power to allow them to do repeated attacks.

I am trying to keep things within the realms of current or near future level technology (with a bit of hand wavery) as that is something I can easily research and what I feel I can paint a better picture of but I think I have put myself into a corner by giving myself that limitation.

So I was wondering if there is a way I can get around the amount of power capable of being stored in a portable sized battery that could be put in a human sized body?

If not, what theorised future possibilities what be a good direction to go in to store vast amounts of power in a small form?

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    $\begingroup$ Is fusion on the table? This would be actual power generation rather than energy storage though. $\endgroup$ – Michael Richardson Dec 4 '19 at 18:48
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    $\begingroup$ Small nit-pick - "plasma projectiles" are not a thing, except in a vacuum. If you're going science-based, that's not a weapon that your androids can have. $\endgroup$ – jdunlop Dec 4 '19 at 18:56
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    $\begingroup$ @jdunlop couldn't a charged particle be sent simultaneously with a high-density puff of argon or helium to produce a sort of short-range plasma projectile? I mean, like in gas tungsten arc welding, so the gas would be burning up as plasma while it moved through space at the same speed as the particle. $\endgroup$ – boxcartenant Dec 4 '19 at 19:01
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    $\begingroup$ @boxcartenant - At which point you're describing a more expensive, finicky, and unreliable RPG launcher. (Plus, if you can emit focused microwaves that can track a target, why not use those directly? I understand Rule of Cool, but weapons designers generally don't go for that.) $\endgroup$ – jdunlop Dec 4 '19 at 19:13
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    $\begingroup$ Fusion in a human sized body isn't within existing or near-term technology. Maybe if we had some kind of highly efficient force field technology. But without that, not going to happen. We can't yet get fusion producing power with any sized device, and are unlikely to get it going with less than 100 ton sized devices. $\endgroup$ – puppetsock Dec 4 '19 at 19:24
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There is no way you can get around this problem with current or near-future technology - energy density is the major problem with battery-electric vehicles, and they're not trying to spend enormous amounts of power with energy weapons.

(Side note: if you're worried about the science-based power constraints, there are major problems with energy weapons integrated into a human-ish body (heat dissipation, thermal bloom, etc.) that are as concerning as "how do I power these weapons".)

As for potential power sources - a miniaturized fusion generator or a matter/antimatter annihilation cell (you wouldn't need much antimatter!) would provide the ability to use integrated energy weapons at length, notwithstanding the side note above. You could also borrow from Heinlein and invent your own Shipstone, an inexplicable energy storage device which packs

more kilowatt-hours into a smaller space and a smaller mass than any other engineer had ever dreamed of. To call it an "improved storage battery" (as some early accounts did) is like calling an H-bomb an "improved firecracker."

Finally, you can use the science-fiction standby of "vacuum/zero-point energy". This obviates the need to carry power around with you, since you can extract it from properties of the universe, but is definitely not founded in reality.

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    $\begingroup$ Both mini fusion plants and animatter power sources have the same problem: they produce intense radiation that is effectively impossible to shield with the amount of matter you could fit into a human-sized chassis. Even "aneutronic" fusion won't help, because it still emits some neutrons and a lot of high energy x and gamma rays. $\endgroup$ – Starfish Prime Dec 4 '19 at 19:38
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    $\begingroup$ @StarfishPrime - I'm assuming these androids are radiation-resistant, because otherwise their integrated weapons are also going to be a problem. If they're not radiation resistant, it won't matter that you can't get the power, because if you use the weapons, you're still doing permanent damage. $\endgroup$ – jdunlop Dec 4 '19 at 19:41
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    $\begingroup$ +1 for antimatter cell. The physics for it are well understood, the problem is producing the antimatter. $\endgroup$ – SurpriseDog Dec 4 '19 at 20:00
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    $\begingroup$ @jdunlop it might matter if the things they have to be around are not also radiation resistant. Plants people and other animals, for example. It also make hiding rather problematic. If they're just terminator style scorched-earth type androids then it won't matter, of course. $\endgroup$ – Starfish Prime Dec 4 '19 at 20:23
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    $\begingroup$ While antimatter may have the power density, harnessing it in a device smaller than a human would require hand-waiving (which OP said is ok). We could create an antimatter battery with current technology if anyone wanted to front the money, but it would require a device on the scale of meters to trap the majority of the gamma and pion radiation, otherwise it just leaks out everywhere. It's been years since I studied it, but I seem to recall designs for antimatter rockets required at minimum a few meters. $\endgroup$ – Loduwijk Dec 5 '19 at 16:42
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There is already a technology which may be applicable for your purposes: radioisotope thermoelectric generators, or RTGs. These convert the heat released by the radioactive decay of unstable elements into electricity, have been around for over 60 years, and have no moving parts. A Plutonium-238 RTG generates 0.57 watts per gram (so a 20 kg RTG would continuously generate 11,400 watts of power, while a human only generates 2,000 while sprinting, so your androids would be quite strong) and only needs 2.5mm of shielding. According to Wikipedia, the power generated by an Pu-238 RTG degrades by about 0.787% each year, so you will need to replace this once in a while. If you really want exotic directed-energy weapons, you would probably have the android carry capacitors which it charged over time and which were then used to power the weapons, but mundane firearms would probably be more practical, and with their increased strength, your android could probably tote around several heavy weapons with ease, such as heavy machine guns, anti-material rifles, automatic grenade launchers, and rocket launchers, which would be sufficient for most destructive purposes.

http://large.stanford.edu/courses/2014/ph240/labonta1/ https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator

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  • $\begingroup$ good idea, thanks $\endgroup$ – RandySavage Dec 8 '19 at 13:56
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manipulate electricity with their bio battery electric organs and I want these characters to have the ability to shoot powerful lasers, plasma projectiles etc but I am unsure how they could store that much power to allow them to do repeated attacks.

jdunlop has the right answer to the specific question you asked, but there's another element to this you didn't ask about that I want to draw your attention to.

If you're using bio-batteries of whatever kind to shoot lasers and so forth, that energy has to come FROM somewhere. Humans technically use several kinds of 'bio-battery' to power our own biological functions, and that energy comes, essentially, from extracting energy stored in the food we eat.

If your bio-cyborgs are going to be carrying kilowatts of stored energy inside them, they're going to either have to eat some truly stupendous quantities of food, or find some other way of recharging those batteries on a regular basis.

Solar isn't really an option because something the size of a human just doesn't have enough surface area to absorb sufficient energy that way. The simplest way would be if they can directly harness electrical current, and charge themselves up just like a Tesla. I feel like there should be some other options but my imagination is failing me just now. I'll come back if I think up something else.

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    $\begingroup$ Also worth noting that converting the chemical energy that we employ to power our bodies ("bio-batteries") to electrical energy to power an energy weapon is going to be hugely inefficient. $\endgroup$ – jdunlop Dec 4 '19 at 19:11
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    $\begingroup$ @jdunlop well, exactly, so ideally the solution is just absorbing electrical energy directly from the environment. I mean, theoretically you could put your feet in a freezer and your head in the oven and turn yourself into a thermoelectric generator, but licking a 220amp outlet would be quicker. $\endgroup$ – Morris The Cat Dec 4 '19 at 19:16
  • $\begingroup$ I was originally thinking of using an electroplaque method to generate the electricity or using electric bacteria which would then be stored in a battery like organ but I believe creating a charge out of water may not work as well and the bacteria couldn't create a lot of power either? $\endgroup$ – RandySavage Dec 4 '19 at 19:20
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    $\begingroup$ @JRams the energy required for what you want the characters to be able to do is SIGNIFICANT. This isn't "absorb heat from the air around you" levels of energy, this is "hold onto the battery cables from a running automobile for a few hours" sort of thing at the very least. Some VERY rough math suggests to me that a weapons-grade laser would drain the battery of a Tesla model S in about sixty seconds of use, so use that as a basis for comparison. $\endgroup$ – Morris The Cat Dec 4 '19 at 20:27
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    $\begingroup$ @JRams - and it's worth noting that a Tesla Model S battery weighs 1200 lbs. $\endgroup$ – jdunlop Dec 4 '19 at 21:10
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Broadcast power!

https://en.wikipedia.org/wiki/Wireless_power_transfer

Can I invoke wireless power transfer without showing Tesla's tower? Nope.

teslas tower

The idea: power things remotely using radiation that can travel thru the air. Your robots have power transmitters back at the base (hopefully a mushroom shaped copper-clad tower) or maybe in orbit, or mounted to the space antenna. They can rapidly charge up. They might unfold a dish to capture the rays; not sure where they would keep that dish between chargings. Cartman from South Park might have ideas.

This idea schemes up some things you might find useful.

Is broadcast power suitable for recharging robots?

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  • $\begingroup$ Interesting, I like this idea thanks. $\endgroup$ – RandySavage Dec 4 '19 at 20:05
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See "Shipstone" in R.A. Heinlein's novel Friday.

See "Molecular Distortion Battery" in Niven's Known Space novels.

Both give it a name, and ignore the details.

H. Beam Piper refers to isotope powered nuclear batteries. The batteries are armoured in collapsium. In effect a single layer of nuclei. About the same weight penalty as a foot of lead. The best reference is in the novel, "The Cosmic Computer"

More near future examples:

A large amount of fuss and feathers some years back about eestor was making a capacitor capable of storing about 50 kWh in little more than a cubic foot. Turned out to be either vapour ware, or quality control issues, but nothing so far has come of it. It used barium titanate, with small impurities for a purported dialectric constant in the range of about 20,000 charged to 3500v. (Capacity is proportional to dialectic and plate area; energy proportional to capacity and the square of voltage.)

Superconductor loops approach energy densities comparable to gasoline. All you would need is some high temp superconductor material. There is no theoretical base I know of that it's impossible, and graphene makes it look possible. Superconductors also superconduct heat. So superconducting armour will be resistant to focused laser/plasma fire.

VERY strong materials (graphene, carbon nano tubes) potentially allow the storage of energy in flywheels. These have angular momentum issues for a combat application. Switzerland has used flywheel powered busses.

Solid carbon fuel cells look interesting. These in theory can convert 80% of the energy in carbon into energy. Currently both fussy and bulky, but the power density may be able to be increased using nano-particle carbon. The battery would have to be kept hot (800C) to work. Has potential at ship sized installations.

That said: Lasers have more waste heat at the source than they deliver to the target. As a weapon they work only by virtue of concentrating that energy is a very small spot. Lasers in air are inefficient. At high power, they ionize the air, then that blocks the beam. Maintaining a good focus at long distances is difficult even with a stationary target, and a rock stable platform.

There's a lot to be said for using a bullet. Chemical energy storage is dense. Most of the energy is delivered to the bullet. Much of the waste energy is in the propellent gasses. (There is still enough energy that barrels and breach get HOT. The Maxim machine gun is water cooled -- and boils the water.) The downside is that it's not as fast.

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  • $\begingroup$ Some great examples and suggestions, thank you $\endgroup$ – RandySavage Dec 5 '19 at 16:20

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