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The good thing is we don’t really need anything better than lithium ion for most applications (aerospace excluded). Solid state electrolyte lithium ion will get

The good thing is we don’t really need anything better than lithium ion for most applications (aerospace excluded). Solid state electrolyte lithium ion will get us to 400Wh/kg, which is more than enough for cheap cars with 400+ mile range.

deleted 8y ago
[deleted]
pmlnr 8y ago
Suuure. And lithium is infinite.
- pfdietz 8y ago
  150 ppb in seawater.
  - hopler 8y ago
    Is it efficient to harvest?
    - pfdietz 8y ago
      Not currently competitive, but the thermodynamic minimum energy goes as the log of dilution.
      - 420codebro 8y ago
        Translate that for me please.
  - pfdietz 8y ago
    As an aside: googling gave various numbers for Li in manganese nodules, but maybe around 100 ppm. There's about a trillion tons (!) of nodules on the ocean floors, so that would be 100 million tons of Li (and billions of tons of cobalt, used in Li-ion electrodes.) This is probably not worth mining just for the Li, but if nodules are mined for other metals (like cobalt) it might also be economical to extract the lithium.
    - pbhjpbhj 8y ago
      We just need cheap batteries first so we can harvest the nodules with robots ...
- imtringued 8y ago
  It is about as infinite as steel.
shrimp_emoji 8y ago
I think the average BEEFY desktop PC uses 300 to 600 W in practice (idle or full load). Let's call it 400 W. 1 kg is 2 lbs. Also, an iPhone 5 is 0.112 kg. If 400 Wh/kg is the best lithium will take us, then we'll never have iPhone 5-sized or weighted devices capable of the same power as a desktop PC, and if we did they'd need to have a battery weighing 1 kg to be capable of it for even one hour. So the mobile and desktop ecosystems will be forever apart. That's sad. Also, what kind of mileage does 400 Wh/kg get you for artificial hearts? (It may be good; I don't know; but, whatever it is, you'd probably like it to be better if you had one.)
- dredmorbius 8y ago
  "Average" varies greatly, but 20-100W is far more typical at idle. https://sustainability.stackexchange.com/questions/5600/how-much-power-does-an-idle-pc-use https://sustainability.stackexchange.com/questions/5600/how-...
- iamgopal 8y ago
  I could argue that more efficient energy storage and processor will make it reality, but then, same logic can also be applied to desktop computing. So ultimate argument becomes, bigger machine will have more power than smaller machine. Ok. Right.
- Terretta 8y ago
  > the average BEEFY desktop PC uses 300 to 600 W in practice ... an iPhone 5 is 0.112 kg ... if 400 Wh/kg is the best lithium will take us, then we'll never have iPhone 5-sized or weighted devices capable of the same power as a desktop PC ... Except that Apple’s A12 is already matching up against Skylake, meaning the iPhone/iPad is currently beating Intel desktops still widely in use. The gap is not so large. https://www.anandtech.com/show/12694/assessing-cavium-thunderx2-arm-server-reality/7 https://www.anandtech.com/show/12694/assessing-cavium-thunde...
  - bscphil 8y ago
    This seems hasty to me... my eight year old laptop processor gets a 7500 on the Geekbench 4 benchmark. According to the first source I found [1], the A12 only gets an 11000. Surely modern components beat my old laptop processor by a huge margin... Even the popular old i7-6700 which came out in 2015 gets a 15000 on the same test. Obviously you have to factor in power use and other requirements, but I would be shocked if anyone with the data to back it up is seriously considering replacing desktop components with something like the A12. (I admit I want this to happen as much as anyone - I would love to see a workstation class PC with 4x ARM processors, for example. I just don't see it being quite economical yet.) [1] https://www.igen.fr/iphone/2018/07/premier-benchmark-dun-mysterieux-iphone-2018-dote-de-4-go-de-ram-104545 https://www.igen.fr/iphone/2018/07/premier-benchmark-dun-mys...
danaos 8y ago
> The good thing is we don’t really need anything better than lithium ion for most applications (aerospace excluded). I highly doubt that you can achieve decent flight times on battery powered plane. The extra battery weight is managed by increasing wing size which in turn translates to higher drag. Higher drag is compensated by more power meaning bigger batteries. It's an engineering nightmare.
- philwelch 8y ago
  Yeah, I looked into this a bit. Planes and rockets absolutely require expendable fuel to achieve efficiency; the ratio of wet to dry mass provides an exponential factor to either flight range or delta-V by virtue of lowering weight as it provides thrust. A lighter flying thing can use less thrust to counteract its own weight (indirectly by generating lift in some cases) thus making its remaining fuel more efficient. This is why the Saturn V had an absolutely gargantuan booster stage, followed by a large booster, then a small booster, and finally a tiny Apollo CSM to actually get to the moon and back. Lifting a rocket itself requires an exponentially bigger market just to get you a few km further off the ground. For planes it’s arguably worse because a plane in level flight thrusts forward and relies on that to indirectly provide lift, whereas weight is always pulling straight down. Also, thrusting forward creates drag backwards.
  - pauljurczak 8y ago
    > Planes and rockets absolutely require expendable fuel to achieve efficiency This may change for planes soon: https://www.eviation.co/ https://www.eviation.co/
- audunw 8y ago
  It should be mentioned that electric motors allow for designs which can drastically lower drag. See NASA X-57 Maxwell for instance. But it will take quite some time for that to translate to commercially made planes. I think the key to electric flight is just a rough doubling of battery capacity, along with finishing the R&D around new designs like the X-57. Nothing that's out of the reach in the near future. A doubling of capacity can be achieved with lithium using either solid state electrolytes or silicon anodes. There's a decent chance that something like that will reach mass production in the next 10 years.
toss1 8y ago
Sure the current ~250Wh/Kg LiIon battery tech gets many jobs done that could not be done with earlier battery technologies. That is not the same thing as saying that further improving the technology would accomplish nothing (as seems to be implied). Gasoline is about 10X that at 2500Wh/Kg (albeit also requires carrying around fuel storage tank(s) & a combustion engine, which is only ~40% efficient on a good day). Getting battery technology up to nearly those energy densities would completely revolutionize everything. Current phones would have 1-2 weeks of battery life, or you could power a pocket workstation (if you could cool it). Ordinary multirotor drones would fly for hours instead of 15-30min. Electric airplanes would be quieter and more efficient.... the possibilities are nearly endless.
systemBuilder 8y ago
That doesn't include the weight of the liquid cooling system which is substantial and which might even INCREASE in weight as the cell energy density increases.
VygmraMGVl 8y ago
Solid state has serious issues with power density and IR heating, the next battery chemistry for cars isn't going to be solid state Li-ion. Magnesium-Air or Zinc-Air are interesting for automotive applications, since they have high specific capacity without sacrificing too much on power. Li-Sulfur also has potential, but it currently suffers from the same problems as Solid State Li.

deleted 8y ago

[deleted]

pmlnr 8y ago

Suuure. And lithium is infinite.

pfdietz 8y ago
150 ppb in seawater.
- hopler 8y ago
  Is it efficient to harvest?
  - pfdietz 8y ago
    Not currently competitive, but the thermodynamic minimum energy goes as the log of dilution.
    - 420codebro 8y ago
      Translate that for me please.
- pfdietz 8y ago
  As an aside: googling gave various numbers for Li in manganese nodules, but maybe around 100 ppm. There's about a trillion tons (!) of nodules on the ocean floors, so that would be 100 million tons of Li (and billions of tons of cobalt, used in Li-ion electrodes.) This is probably not worth mining just for the Li, but if nodules are mined for other metals (like cobalt) it might also be economical to extract the lithium.
  - pbhjpbhj 8y ago
    We just need cheap batteries first so we can harvest the nodules with robots ...
imtringued 8y ago
It is about as infinite as steel.

shrimp_emoji 8y ago

I think the average BEEFY desktop PC uses 300 to 600 W in practice (idle or full load). Let's call it 400 W. 1 kg is 2 lbs. Also, an iPhone 5 is 0.112 kg. If 400 Wh/kg is the best lithium will take us, then we'll never have iPhone 5-sized or weighted devices capable of the same power as a desktop PC, and if we did they'd need to have a battery weighing 1 kg to be capable of it for even one hour. So the mobile and desktop ecosystems will be forever apart. That's sad. Also, what kind of mileage does 400 Wh/kg get you for artificial hearts? (It may be good; I don't know; but, whatever it is, you'd probably like it to be better if you had one.)

dredmorbius 8y ago
"Average" varies greatly, but 20-100W is far more typical at idle. https://sustainability.stackexchange.com/questions/5600/how-much-power-does-an-idle-pc-use https://sustainability.stackexchange.com/questions/5600/how-...
iamgopal 8y ago
I could argue that more efficient energy storage and processor will make it reality, but then, same logic can also be applied to desktop computing. So ultimate argument becomes, bigger machine will have more power than smaller machine. Ok. Right.
Terretta 8y ago
> the average BEEFY desktop PC uses 300 to 600 W in practice ... an iPhone 5 is 0.112 kg ... if 400 Wh/kg is the best lithium will take us, then we'll never have iPhone 5-sized or weighted devices capable of the same power as a desktop PC ... Except that Apple’s A12 is already matching up against Skylake, meaning the iPhone/iPad is currently beating Intel desktops still widely in use. The gap is not so large. https://www.anandtech.com/show/12694/assessing-cavium-thunderx2-arm-server-reality/7 https://www.anandtech.com/show/12694/assessing-cavium-thunde...
- bscphil 8y ago
  This seems hasty to me... my eight year old laptop processor gets a 7500 on the Geekbench 4 benchmark. According to the first source I found [1], the A12 only gets an 11000. Surely modern components beat my old laptop processor by a huge margin... Even the popular old i7-6700 which came out in 2015 gets a 15000 on the same test. Obviously you have to factor in power use and other requirements, but I would be shocked if anyone with the data to back it up is seriously considering replacing desktop components with something like the A12. (I admit I want this to happen as much as anyone - I would love to see a workstation class PC with 4x ARM processors, for example. I just don't see it being quite economical yet.) [1] https://www.igen.fr/iphone/2018/07/premier-benchmark-dun-mysterieux-iphone-2018-dote-de-4-go-de-ram-104545 https://www.igen.fr/iphone/2018/07/premier-benchmark-dun-mys...

danaos 8y ago

> The good thing is we don’t really need anything better than lithium ion for most applications (aerospace excluded). I highly doubt that you can achieve decent flight times on battery powered plane. The extra battery weight is managed by increasing wing size which in turn translates to higher drag. Higher drag is compensated by more power meaning bigger batteries. It's an engineering nightmare.

philwelch 8y ago
Yeah, I looked into this a bit. Planes and rockets absolutely require expendable fuel to achieve efficiency; the ratio of wet to dry mass provides an exponential factor to either flight range or delta-V by virtue of lowering weight as it provides thrust. A lighter flying thing can use less thrust to counteract its own weight (indirectly by generating lift in some cases) thus making its remaining fuel more efficient. This is why the Saturn V had an absolutely gargantuan booster stage, followed by a large booster, then a small booster, and finally a tiny Apollo CSM to actually get to the moon and back. Lifting a rocket itself requires an exponentially bigger market just to get you a few km further off the ground. For planes it’s arguably worse because a plane in level flight thrusts forward and relies on that to indirectly provide lift, whereas weight is always pulling straight down. Also, thrusting forward creates drag backwards.
- pauljurczak 8y ago
  > Planes and rockets absolutely require expendable fuel to achieve efficiency This may change for planes soon: https://www.eviation.co/ https://www.eviation.co/
audunw 8y ago
It should be mentioned that electric motors allow for designs which can drastically lower drag. See NASA X-57 Maxwell for instance. But it will take quite some time for that to translate to commercially made planes. I think the key to electric flight is just a rough doubling of battery capacity, along with finishing the R&D around new designs like the X-57. Nothing that's out of the reach in the near future. A doubling of capacity can be achieved with lithium using either solid state electrolytes or silicon anodes. There's a decent chance that something like that will reach mass production in the next 10 years.

toss1 8y ago

Sure the current ~250Wh/Kg LiIon battery tech gets many jobs done that could not be done with earlier battery technologies. That is not the same thing as saying that further improving the technology would accomplish nothing (as seems to be implied). Gasoline is about 10X that at 2500Wh/Kg (albeit also requires carrying around fuel storage tank(s) & a combustion engine, which is only ~40% efficient on a good day). Getting battery technology up to nearly those energy densities would completely revolutionize everything. Current phones would have 1-2 weeks of battery life, or you could power a pocket workstation (if you could cool it). Ordinary multirotor drones would fly for hours instead of 15-30min. Electric airplanes would be quieter and more efficient.... the possibilities are nearly endless.

systemBuilder 8y ago

That doesn't include the weight of the liquid cooling system which is substantial and which might even INCREASE in weight as the cell energy density increases.

VygmraMGVl 8y ago

Solid state has serious issues with power density and IR heating, the next battery chemistry for cars isn't going to be solid state Li-ion. Magnesium-Air or Zinc-Air are interesting for automotive applications, since they have high specific capacity without sacrificing too much on power. Li-Sulfur also has potential, but it currently suffers from the same problems as Solid State Li.