10 ms·

Eternally five years away? No, batteries are improving under your nose

98 points by leephillips 5y ago

SigmundA 5y ago
Definitely something I missed when I was more skeptical about BEV's and Tesla a few years ago. It's not about some new breakthrough to make batteries as cheap or energy dense as gas, it's a steady YoY improvement and steady decline in prices. Lithium batteries where developed in the 70's didn't get released until the 90's and has steadily improved since then with a big cost decline in the last few years. They are currently up around 300 wh/kg with a theoretical peak of around 2600 wh/kg with sulfur cathodes there is still plenty of headroom for further improvement. At around 2000 wh/kg it roughly equivalent to a diesel drivetrain power density if my math is right.
- gwbas1c 5y ago
  Years ago I went to a presentation by Tesla in the Bay Area because they were going to let people sit in one of the early prototype Roadsters. They basically explained that they were betting the company on a "Moore's Law" of batteries. The presentation included a graph of battery capacity doubling every 7 years.
  - dochtman 5y ago
    If you look at the chart in this article, it looks like energy density has been on a linear rather than exponential path for the last three decades.
  - m463 5y ago
    I think that moore's law was a huge contributor to the success of silicon valley. It let people predict the future 2 or 4 or 10 years out, from the conservative people in charge of finances to the wildcats who are creating new technology that will need something cheap or fast or just viable to match up with when they ship.
- mavhc 5y ago
  Tesla's 50% reduction in cost of their new batteries is made up of 50 different things
- teddyh 5y ago
  > developed in the 70's didn't get released until the 90's Patents last for 20 years.
  - dv_dt 5y ago
    Oddly enough it doesn't prevent semiconductor technology from advancing - don't know if it's from cross-licensing or something else?
    - to11mtm 5y ago
      Cross licensing definitely had a part in it. Some of that was necessity, either practical or contractual. In the 70s, before Projection Masking as a fabrication technique came into play, more complex designs could have yields as bad as 10%. As a result, 'Second Sourcing' was more frequent, and while Intel and AMD had some Cross Licensing before x86, the main reason the agreement expanded to include x86 was because IBM was still requiring Second Sources in the 80s. I know at one point, Chevron had it's tentacles on some NIMH patents via their control of Ovonics. Not sure if there are/were any similar situations for Lithium Ion technology. Also the price fixing done by Lithium companies between 2000-2011. That likely hampered adoption and perhaps improvements.
- leephillips 5y ago
  2000 wh/kg (crazy units, but I guess this is conventional in some fields?) is 7.2MJ/kg. Diesel fuel and gasoline are something like 40MJ/kg. So same ballpark.
  - gizmo686 5y ago
    Also, electric motors can easily reach 80%-90% efficiency, while ICE engines in cars typically get 20%-35%. Even in principle ICE engines are thermodynamicly required to be inefficient as combustion itself produces heat, and there is a limit to how much useful work you can extract from a thermal gradient. You still need to account for the discharge efficiency of the battery (which I cannot find numbers for). For overall energy usage, electric still still has whatever inefficiencies exist in the generator (and charging inefficiency), but those don't effect power density
    - ianai 5y ago
      The inefficiency inclusion from the generator for electric is somewhat unrelated to an ICE. No ones including the inefficiency of extracting and refining the oil, the huge amounts of time/energy required within the earths crust to create the oil, nor the energy conversion from the sun into organic matter in the first place. It seems a lot of the details on the fossil fuel side get left out.
    - cogman10 5y ago
      Discharge efficiency varies from battery to battery. Generally speaking, it's a 90+% efficient process (as is charging). However, there are certainly exceptions which are more or less efficient. Transmission costs probably eat a bigger portion of EV total efficiency. Those depend on how far you are from your power source and what voltage your power is transmitted at. That said, a thing EVs do that ICEs can't is accept power from any source. That means that only a fraction of the fuel is actually generated from a fossil fuel. One other thing to consider is that as power density goes up for batteries, the amount of required batteries go down, ultimately reducing vehicle weight and improving range. Assuming batteries were ever 10x their current power density, you'd probably not see cars with 10x range, rather, you'd see something like 400mile range cars with the same total power capacity of yesteryear cars. Pretty much all because you've cut the pack weight down by 1/10th (probably less because you need a lot less infrastructure around maintaining temperature for 1/10th the number of batteries).
- Gibbon1 5y ago
  When I've tried to work out estimates, currently EV's suffer a 20-25% weight penalty over gas/diesel. Part of the weight penalty is due to cascading effects. A battery plus and electric motor weighs more than a gas tank plus engine/transmission. Which means the structural elements have to be heavier. I think if batteries energy density increases by 50% the weight penalty goes away.
  - sunstone 5y ago
    All true but on the good side the weight distribution of the BEV batteries is much better than the weight distribution of the ICE power train. So it's not all just about the amount of weight.
    - olyjohn 5y ago
      Is weight distribution really helpful for anything other than handling?
- v77 5y ago
  This is also why I've become a bit more skeptical about Nuclear. Renewables + batteries are pretty mediocre right now but if I'm to bet on something for the next twenty years, it's that.
  - SigmundA 5y ago
    I think nuclear is still really important and has a lot of room for improvement. It's hard to beat its output stability and energy density while emitting no carbon. Just have to figure out how to keep it safe.
    - amanaplanacanal 5y ago
      Just have to figure out how to make it cost less than other energy sources.
      - TheAdamAndChe 5y ago
        Small modular reactors are probably our best bet here. Centrally manufactured, fail-safe designs, short on-site construction times and time-to-first-power-output. It all depends at this point on if the regulatory environment can be improved soon enough for it to matter.
    - ashtonkem 5y ago
      Nuclear is already incredibly safe. Installing solar has probably killed more people than nuclear ever has.
  - imtringued 5y ago
    Nuclear is ok for district heating because there aren't many alternatives. Burning gas 20% of the time as backup is not as big of a problem as many people make it out to be. The atmosphere doesn't care when you pollute, just how much, so intermittency is one of the biggest red herrings of all time. If we had grids with 80% renewables you can start thinking about grid storage but right now it doesn't matter that much.
helsinkiandrew 5y ago
This happens with just about all technologies: it takes 5 (or 10, or 20) years for the next jump technology to come to market in quantity, but meanwhile the existing technology gets iteratively improved and made cheaper to manufacture - Battery, Solar, Semiconductors. Often so much that it makes the jump to the new technology not worth it.
- hliyan 5y ago
  On a related note, the first Perovskite based solar cells are due to hit markets this year (after many years of being thought of as too impractical to leave the lab).
coldtea 5y ago
Well, not at the promised rate, because they're not 1000x as efficient (which they would be promised in article upon article over 4 decades and compounded).
- sthnblllII 5y ago
  And they never will be. We are at the limit of safe battery energy density. https://m.youtube.com/watch?v=8RbwOhM6PUk https://m.youtube.com/watch?v=8RbwOhM6PUk
  - Hypx_ 5y ago
    The other issue is recyclability. Modern li-ion batteries are basically superglued together in order to maximize energy density. A pack designed with recycling in mind will have to be more easily taken apart and likely significantly heavier.
    - sunstone 5y ago
      My understanding is currently they just grind up the old batteries into a kind of slurry that then goes through a uniform series of processes to recover the various components.
      - Hypx_ 5y ago
        A process that has both huge losses and requires enormous amounts of energy.
aeturnum 5y ago
Batteries are getting better, but we'll almost certainly never reach the fantasy of replacing petrochemicals with batteries 1:1. Instead, what we can do is change our patterns of energy consumption and then we'll start to feel the gains from battery improvement in a more visceral way. Different technologies are just different. Improvements to batteries will make them a little better at being dropped in as a gasoline replacement, but exponentially better at use cases designed with the lifecycles and energy densities that batteries can comfortably support.
- deleted 5y ago
  [deleted]
mikewarot 5y ago
While a lot of focus has been placed on vehicle batteries, I wonder how things are going with stationary batteries, where weight and space are far less important.
Hypx_ 5y ago
Of course, no such article ever points out that hydrogen-air batteries already exist and have a 40,000 Wh/kg energy density.
- swiley 5y ago
  Hydrogen and any gas with 30% oxygen doesn't sound like a good mixture to have in your pocket.
  - Hypx_ 5y ago
    You don't combined the hydrogen with anything until the moment of reaction.
- dokem 5y ago
  The pressure vessels are just not something you want in a consumer vehicle.
  - Hypx_ 5y ago
    The pressure vessels are arguably safer than either batteries or gas tanks.
    - dokem 5y ago
      Who's arguing? You or experts?

98 points by leephillips 5y ago

Definitely something I missed when I was more skeptical about BEV's and Tesla a few years ago. It's not about some new breakthrough to make batteries as cheap or energy dense as gas, it's a steady YoY improvement and steady decline in prices. Lithium batteries where developed in the 70's didn't get released until the 90's and has steadily improved since then with a big cost decline in the last few years. They are currently up around 300 wh/kg with a theoretical peak of around 2600 wh/kg with sulfur cathodes there is still plenty of headroom for further improvement. At around 2000 wh/kg it roughly equivalent to a diesel drivetrain power density if my math is right.

gwbas1c 5y ago
Years ago I went to a presentation by Tesla in the Bay Area because they were going to let people sit in one of the early prototype Roadsters. They basically explained that they were betting the company on a "Moore's Law" of batteries. The presentation included a graph of battery capacity doubling every 7 years.
- dochtman 5y ago
  If you look at the chart in this article, it looks like energy density has been on a linear rather than exponential path for the last three decades.
- m463 5y ago
  I think that moore's law was a huge contributor to the success of silicon valley. It let people predict the future 2 or 4 or 10 years out, from the conservative people in charge of finances to the wildcats who are creating new technology that will need something cheap or fast or just viable to match up with when they ship.
mavhc 5y ago
Tesla's 50% reduction in cost of their new batteries is made up of 50 different things
teddyh 5y ago
> developed in the 70's didn't get released until the 90's Patents last for 20 years.
- dv_dt 5y ago
  Oddly enough it doesn't prevent semiconductor technology from advancing - don't know if it's from cross-licensing or something else?
  - to11mtm 5y ago
    Cross licensing definitely had a part in it. Some of that was necessity, either practical or contractual. In the 70s, before Projection Masking as a fabrication technique came into play, more complex designs could have yields as bad as 10%. As a result, 'Second Sourcing' was more frequent, and while Intel and AMD had some Cross Licensing before x86, the main reason the agreement expanded to include x86 was because IBM was still requiring Second Sources in the 80s. I know at one point, Chevron had it's tentacles on some NIMH patents via their control of Ovonics. Not sure if there are/were any similar situations for Lithium Ion technology. Also the price fixing done by Lithium companies between 2000-2011. That likely hampered adoption and perhaps improvements.
leephillips 5y ago
2000 wh/kg (crazy units, but I guess this is conventional in some fields?) is 7.2MJ/kg. Diesel fuel and gasoline are something like 40MJ/kg. So same ballpark.
- gizmo686 5y ago
  Also, electric motors can easily reach 80%-90% efficiency, while ICE engines in cars typically get 20%-35%. Even in principle ICE engines are thermodynamicly required to be inefficient as combustion itself produces heat, and there is a limit to how much useful work you can extract from a thermal gradient. You still need to account for the discharge efficiency of the battery (which I cannot find numbers for). For overall energy usage, electric still still has whatever inefficiencies exist in the generator (and charging inefficiency), but those don't effect power density
  - ianai 5y ago
    The inefficiency inclusion from the generator for electric is somewhat unrelated to an ICE. No ones including the inefficiency of extracting and refining the oil, the huge amounts of time/energy required within the earths crust to create the oil, nor the energy conversion from the sun into organic matter in the first place. It seems a lot of the details on the fossil fuel side get left out.
  - cogman10 5y ago
    Discharge efficiency varies from battery to battery. Generally speaking, it's a 90+% efficient process (as is charging). However, there are certainly exceptions which are more or less efficient. Transmission costs probably eat a bigger portion of EV total efficiency. Those depend on how far you are from your power source and what voltage your power is transmitted at. That said, a thing EVs do that ICEs can't is accept power from any source. That means that only a fraction of the fuel is actually generated from a fossil fuel. One other thing to consider is that as power density goes up for batteries, the amount of required batteries go down, ultimately reducing vehicle weight and improving range. Assuming batteries were ever 10x their current power density, you'd probably not see cars with 10x range, rather, you'd see something like 400mile range cars with the same total power capacity of yesteryear cars. Pretty much all because you've cut the pack weight down by 1/10th (probably less because you need a lot less infrastructure around maintaining temperature for 1/10th the number of batteries).
Gibbon1 5y ago
When I've tried to work out estimates, currently EV's suffer a 20-25% weight penalty over gas/diesel. Part of the weight penalty is due to cascading effects. A battery plus and electric motor weighs more than a gas tank plus engine/transmission. Which means the structural elements have to be heavier. I think if batteries energy density increases by 50% the weight penalty goes away.
- sunstone 5y ago
  All true but on the good side the weight distribution of the BEV batteries is much better than the weight distribution of the ICE power train. So it's not all just about the amount of weight.
  - olyjohn 5y ago
    Is weight distribution really helpful for anything other than handling?
v77 5y ago
This is also why I've become a bit more skeptical about Nuclear. Renewables + batteries are pretty mediocre right now but if I'm to bet on something for the next twenty years, it's that.
- SigmundA 5y ago
  I think nuclear is still really important and has a lot of room for improvement. It's hard to beat its output stability and energy density while emitting no carbon. Just have to figure out how to keep it safe.
  - amanaplanacanal 5y ago
    Just have to figure out how to make it cost less than other energy sources.
    - TheAdamAndChe 5y ago
      Small modular reactors are probably our best bet here. Centrally manufactured, fail-safe designs, short on-site construction times and time-to-first-power-output. It all depends at this point on if the regulatory environment can be improved soon enough for it to matter.
  - ashtonkem 5y ago
    Nuclear is already incredibly safe. Installing solar has probably killed more people than nuclear ever has.
- imtringued 5y ago
  Nuclear is ok for district heating because there aren't many alternatives. Burning gas 20% of the time as backup is not as big of a problem as many people make it out to be. The atmosphere doesn't care when you pollute, just how much, so intermittency is one of the biggest red herrings of all time. If we had grids with 80% renewables you can start thinking about grid storage but right now it doesn't matter that much.

helsinkiandrew 5y ago

This happens with just about all technologies: it takes 5 (or 10, or 20) years for the next jump technology to come to market in quantity, but meanwhile the existing technology gets iteratively improved and made cheaper to manufacture - Battery, Solar, Semiconductors. Often so much that it makes the jump to the new technology not worth it.

hliyan 5y ago
On a related note, the first Perovskite based solar cells are due to hit markets this year (after many years of being thought of as too impractical to leave the lab).

coldtea 5y ago

Well, not at the promised rate, because they're not 1000x as efficient (which they would be promised in article upon article over 4 decades and compounded).

sthnblllII 5y ago
And they never will be. We are at the limit of safe battery energy density. https://m.youtube.com/watch?v=8RbwOhM6PUk https://m.youtube.com/watch?v=8RbwOhM6PUk
- Hypx_ 5y ago
  The other issue is recyclability. Modern li-ion batteries are basically superglued together in order to maximize energy density. A pack designed with recycling in mind will have to be more easily taken apart and likely significantly heavier.
  - sunstone 5y ago
    My understanding is currently they just grind up the old batteries into a kind of slurry that then goes through a uniform series of processes to recover the various components.
    - Hypx_ 5y ago
      A process that has both huge losses and requires enormous amounts of energy.

aeturnum 5y ago

Batteries are getting better, but we'll almost certainly never reach the fantasy of replacing petrochemicals with batteries 1:1. Instead, what we can do is change our patterns of energy consumption and then we'll start to feel the gains from battery improvement in a more visceral way. Different technologies are just different. Improvements to batteries will make them a little better at being dropped in as a gasoline replacement, but exponentially better at use cases designed with the lifecycles and energy densities that batteries can comfortably support.

deleted 5y ago
[deleted]

mikewarot 5y ago

While a lot of focus has been placed on vehicle batteries, I wonder how things are going with stationary batteries, where weight and space are far less important.

Hypx_ 5y ago

Of course, no such article ever points out that hydrogen-air batteries already exist and have a 40,000 Wh/kg energy density.

swiley 5y ago
Hydrogen and any gas with 30% oxygen doesn't sound like a good mixture to have in your pocket.
- Hypx_ 5y ago
  You don't combined the hydrogen with anything until the moment of reaction.
dokem 5y ago
The pressure vessels are just not something you want in a consumer vehicle.
- Hypx_ 5y ago
  The pressure vessels are arguably safer than either batteries or gas tanks.
  - dokem 5y ago
    Who's arguing? You or experts?