5 ms·

> a lot of them did Really? I haven't noticed much progress over the last 5 to 10 years. What was the biggest breakthrough that has materialized in that time?

xoa 5y ago
>Really? I haven't noticed much progress over the last 5 to 10 years You don't call doubling to tripling of energy density progress? https://cleantechnica.com/2020/02/19/bloombergnef-lithium-ion-battery-cell-densities-have-almost-tripled-since-2010/ https://cleantechnica.com/2020/02/19/bloombergnef-lithium-io... And it's not about "big breakthroughs" any more than it is for microprocessors. A bunch of lab changes that in production add .5-5% each add up to 10-20% in a generation add up to 2-3x over a decade. That something works in a lab though is still interesting since it shows the possible ceiling we can work towards. Going from that to something that we can make billions of cheaply entails compromises, but the ultimate envelope still matters.
- multiplegeorges 5y ago
  Just like in finance, most (consumer/laymen) people are looking for a big win when it's been shown over and over that small gains compounded over time always come out ahead.
- magila 5y ago
  So this got me curious and I started to look at something a bit more concrete: the history of 18650 cell capacity. Currently the highest capacity 18650 that's widely available is 3500 mAh. The first such cell I found is the LG MJ1 which dates back to 2014: https://cdn.shopify.com/s/files/1/0481/9678/0183/files/lg_mj1_data_sheet.pdf https://cdn.shopify.com/s/files/1/0481/9678/0183/files/lg_mj... I also found a 3200 mAh model from 2012: https://cdn.shopify.com/s/files/1/0481/9678/0183/files/panasonic_18650b_data_sheet.pdf https://cdn.shopify.com/s/files/1/0481/9678/0183/files/panas... That's a fair bit less than a 3x improvement over 10 years. Now of course this is a rather crude and unscientific measurement. It's also effectively measuring energy density by volume rather than weight, but volume is more often the limiting factor for Li-ion batteries (e.g. smartphones and EVs are volume limited). Still, I think this shows why people are skeptical about claimed massive improvements in battery tech: it's hard to find clear evidence of it in actual products people can buy.
  - simonh 5y ago
    So far as I can tell Li Ion batteries have gained about a 1.5x charge per mass improvement in the last 10 years. They may have doubled or trebled over a longer time frame though. If there was a big jump due to a particular technology an extra year or two in the time frame, or shift in the time frame might make a big difference.
- gpapilion 5y ago
  I think while the energy density has doubled the amount observed work from a battery seems constant. Laptops last a few hours, phones last around a day, etc. We’ve used that density to get thinner and lighter devices with slightly more performance that’s hard to observe from everyday tasks. The outlier is cars, where they’ve crept up as the density has come up.
  - moonchrome 5y ago
    >I think while the energy density has doubled Has it really ? I remember the same mAh ratings or slight bumps in phones for many generations. 2016 Samsung galaxy s7 had 3000mah battery - latest ones have like 3700mah ? There have been larger batteries in bigger phones - but I'd like to have a 6000mah battery in a normal form factor. The only doubling I see is in 10 year period, but phone size grew considerably in that time as well. And smart watch batteries still suck no matter the price range.
    - simonh 5y ago
      You’re not taking into account the weight of those batteries or their cost as components. A bigger phone might not just have a bigger battery, it might have a bigger cheaper battery with the same capacity. Only looking at the capacity doesn’t tell you anything useful about charge to weight.
- RivieraKid 5y ago
  This chart is a little suspicious given that iPhone battery density has only increased by 20% in 9 years. https://twitter.com/Alxbk/status/1181307722991652864 https://twitter.com/Alxbk/status/1181307722991652864
  - zardo 5y ago
    Apple isn't going to be selecting for mass/energy density. That's a major concern for EVs, but for a phone, you would gladly take double the capacity for 3x the mass.
    - magila 5y ago
      EV battery capacity hasn't exactly been skyrocketing either. When the Tesla Model S was introduced in 2012 the largest battery option was 85 kWh. For the 2015 model year it got a 90 kWh option and 100 kWh for 2016. Today 100 kWh remains the most you can get.
      - zardo 5y ago
        How has the mass changed? If we're talking about a fraction (density) it's pointless to talk about the numerator on its own.
        magila 5y ago
        I can't find any indication that the weight of Tesla batteries has changed significantly since the introduction of the 100 kWh pack. In any case weight savings on Tesla batteries seems to have come primarily from improved packaging rather than better chemistries.
  - robocat 5y ago
    Mobile phones mostly optimise for Wh/m³ or for batteries more usually stated Wh/L (stored energy by volume), however that tweet is about Wh/kg (stored energy by weight) which is less relevant to mobile phones. “Density” means one thing that has little to do with energy, “energy density” https://en.wikipedia.org/wiki/Energy_density https://en.wikipedia.org/wiki/Energy_density is a slightly better term but it is also misused. “volumetric energy density” versus “gravimetric energy density” are clearer terms (edit:) for usage in conversations like this, although the more standard industry terms afaik are “energy density” for volumetric and “specific energy” for gravimetric.
gameswithgo 5y ago

xoa 5y ago

>Really? I haven't noticed much progress over the last 5 to 10 years You don't call doubling to tripling of energy density progress? https://cleantechnica.com/2020/02/19/bloombergnef-lithium-ion-battery-cell-densities-have-almost-tripled-since-2010/ https://cleantechnica.com/2020/02/19/bloombergnef-lithium-io... And it's not about "big breakthroughs" any more than it is for microprocessors. A bunch of lab changes that in production add .5-5% each add up to 10-20% in a generation add up to 2-3x over a decade. That something works in a lab though is still interesting since it shows the possible ceiling we can work towards. Going from that to something that we can make billions of cheaply entails compromises, but the ultimate envelope still matters.

multiplegeorges 5y ago
Just like in finance, most (consumer/laymen) people are looking for a big win when it's been shown over and over that small gains compounded over time always come out ahead.
magila 5y ago
So this got me curious and I started to look at something a bit more concrete: the history of 18650 cell capacity. Currently the highest capacity 18650 that's widely available is 3500 mAh. The first such cell I found is the LG MJ1 which dates back to 2014: https://cdn.shopify.com/s/files/1/0481/9678/0183/files/lg_mj1_data_sheet.pdf https://cdn.shopify.com/s/files/1/0481/9678/0183/files/lg_mj... I also found a 3200 mAh model from 2012: https://cdn.shopify.com/s/files/1/0481/9678/0183/files/panasonic_18650b_data_sheet.pdf https://cdn.shopify.com/s/files/1/0481/9678/0183/files/panas... That's a fair bit less than a 3x improvement over 10 years. Now of course this is a rather crude and unscientific measurement. It's also effectively measuring energy density by volume rather than weight, but volume is more often the limiting factor for Li-ion batteries (e.g. smartphones and EVs are volume limited). Still, I think this shows why people are skeptical about claimed massive improvements in battery tech: it's hard to find clear evidence of it in actual products people can buy.
- simonh 5y ago
  So far as I can tell Li Ion batteries have gained about a 1.5x charge per mass improvement in the last 10 years. They may have doubled or trebled over a longer time frame though. If there was a big jump due to a particular technology an extra year or two in the time frame, or shift in the time frame might make a big difference.
gpapilion 5y ago
I think while the energy density has doubled the amount observed work from a battery seems constant. Laptops last a few hours, phones last around a day, etc. We’ve used that density to get thinner and lighter devices with slightly more performance that’s hard to observe from everyday tasks. The outlier is cars, where they’ve crept up as the density has come up.
- moonchrome 5y ago
  >I think while the energy density has doubled Has it really ? I remember the same mAh ratings or slight bumps in phones for many generations. 2016 Samsung galaxy s7 had 3000mah battery - latest ones have like 3700mah ? There have been larger batteries in bigger phones - but I'd like to have a 6000mah battery in a normal form factor. The only doubling I see is in 10 year period, but phone size grew considerably in that time as well. And smart watch batteries still suck no matter the price range.
  - simonh 5y ago
    You’re not taking into account the weight of those batteries or their cost as components. A bigger phone might not just have a bigger battery, it might have a bigger cheaper battery with the same capacity. Only looking at the capacity doesn’t tell you anything useful about charge to weight.
RivieraKid 5y ago
This chart is a little suspicious given that iPhone battery density has only increased by 20% in 9 years. https://twitter.com/Alxbk/status/1181307722991652864 https://twitter.com/Alxbk/status/1181307722991652864
- zardo 5y ago
  Apple isn't going to be selecting for mass/energy density. That's a major concern for EVs, but for a phone, you would gladly take double the capacity for 3x the mass.
  - magila 5y ago
    EV battery capacity hasn't exactly been skyrocketing either. When the Tesla Model S was introduced in 2012 the largest battery option was 85 kWh. For the 2015 model year it got a 90 kWh option and 100 kWh for 2016. Today 100 kWh remains the most you can get.
    - zardo 5y ago
      How has the mass changed? If we're talking about a fraction (density) it's pointless to talk about the numerator on its own.
      - magila 5y ago
        I can't find any indication that the weight of Tesla batteries has changed significantly since the introduction of the 100 kWh pack. In any case weight savings on Tesla batteries seems to have come primarily from improved packaging rather than better chemistries.
- robocat 5y ago
  Mobile phones mostly optimise for Wh/m³ or for batteries more usually stated Wh/L (stored energy by volume), however that tweet is about Wh/kg (stored energy by weight) which is less relevant to mobile phones. “Density” means one thing that has little to do with energy, “energy density” https://en.wikipedia.org/wiki/Energy_density https://en.wikipedia.org/wiki/Energy_density is a slightly better term but it is also misused. “volumetric energy density” versus “gravimetric energy density” are clearer terms (edit:) for usage in conversations like this, although the more standard industry terms afaik are “energy density” for volumetric and “specific energy” for gravimetric.

gameswithgo 5y ago