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The article is short on information on the battery itself but thankfully there is a Wikipedia entry for it: https://en.m.wikipedia.org/wiki/Blade_Battery https

The article is short on information on the battery itself but thankfully there is a Wikipedia entry for it: https://en.m.wikipedia.org/wiki/Blade_Battery https://en.m.wikipedia.org/wiki/Blade_Battery

catchnear4321 3y ago
thanks for the link, the “article” can’t even keep it on the rails for the intro. > The heart of any electric car is the battery. one way to look at it, sure. > It makes up around 40% of the value… well, that seems a bit arbitrary, but as not an expert myself, seems… fine. > …and we rely on it to keep us moving. well, sure, it is a required part of the car. we also rely on the wheels to keep us moving. > And yet we know very little about them. what in the actual…
- tzs 3y ago
  I remember in a solid state chemistry MOOC I took, from a professor who was a lithium battery researcher, the professor did mention in passing that we actually don't have a really good understanding of lithium batteries. Of course he was talking about a much lower level than you need to understand when it comes to actually using them. There are actually a lot of things we know how to deal with when it comes to engineering but have a poor grasp of the low level details. There was a great example in the Feynman Lectures where he says this about friction (Volume 1, section 12-2): > It is quite difficult to do accurate quantitative experiments in friction, and the laws of friction are still not analyzed very well, in spite of the enormous engineering value of an accurate analysis. Although the law F=μN is fairly accurate once the surfaces are standardized, the reason for this form of the law is not really understood. To show that the coefficient μ is nearly independent of velocity requires some delicate experimentation, because the apparent friction is much reduced if the lower surface vibrates very fast. When the experiment is done at very high speed, care must be taken that the objects do not vibrate relative to one another, since apparent decreases of the friction at high speed are often due to vibrations. At any rate, this friction law is another of those semiempirical laws that are not thoroughly understood, and in view of all the work that has been done it is surprising that more understanding of this phenomenon has not come about. At the present time, in fact, it is impossible even to estimate the coefficient of friction between two substances. That was written around 60 years ago. Anyone here happen to know if it still holds?
  - user_7832 3y ago
    > That was written around 60 years ago. Anyone here happen to know if it still holds? Not really the same question but I attended a talk by some top tribologists at my uni and I asked them if friction really was independent of contact area (as F=μN would suggest), their reply was that it roughly was, but not really if you were very precise or varying parameters. It would appear that the equation is a good approximation, like classical Newtonian physics.
  - _a_a_a_ 3y ago
    Apparently even solubility of compounds in various solvents is empirically derived because there's no reliable theoretical model of this in chemistry/physics. (AIUI anyway)
    - catchnear4321 3y ago
      not to get too leaky, and this is a bit dated, but… the math produces results that are understood but not, because the math is calculating with some implicit inclusions, and things get weird when you start explicitly including. the answers make sense, but not quite for the questions being asked. (but the answers are valid for a question, and more importantly, immediately useful for making dollars.) unfortunately the vagueness of this will likely irritate a doctor. it certainly did years ago.
  - photochemsyn 3y ago
    At some point, scale-wise, friction problems become electrochemical rate problems, I suppose. See this recently published research article on lithium iron phosphate batteries, opening: > "Reaction rates at spatially heterogeneous, unstable interfaces are notoriously difficult to quantify, yet are essential in engineering many chemical systems, such as batteries and electrocatalysts..." https://www.nature.com/articles/s41586-023-06393-x https://www.nature.com/articles/s41586-023-06393-x It's a much harder problem than working with pure crystals or gas-phase molecules or similar, which makes sense, as a half-discharged battery is a very messy system at the molecular-atomic level. See also news story on the above article: > “We discovered at the nano scale that variation of the carbon coating thickness directly controls the rate, which is something you could never figure out if you didn't have all of this modeling and image analysis,” Bazant says. https://news.mit.edu/2023/pixel-analysis-yields-insights-lithium-ion-batteries-0913 https://news.mit.edu/2023/pixel-analysis-yields-insights-lit... So, the field seems to be progressing steadily - and more funding for fundamental solid-state materials science research makes sense, too.
- joosters 3y ago
  And: > But BYD is also a car maker in its own right Yeah, it's actually the largest electric car manufacturer in the whole world.
  - eunos 3y ago
    BYD actually started as a battery maker.
  - DoesntMatter22 3y ago
    Only if you consider a hybrid to be an electric car. Tesla is still bigger on BEVs
    - xbmcuser 3y ago
      They are expected to get ahead of Tesla end of this year.
      - DoesntMatter22 3y ago
        Most things I've seen say next year. Regardless, it's not a fact that they are the biggest yet.
deleted 3y ago
[deleted]
throwawaymaths 3y ago
Lfp chemistry is not that innovative -- it's in use in homes for sure and I think also tesla uses them. Given the breathlessness of the article I expected sodium batteries or something
- Voultapher 3y ago
  Wasn't there news recently that a big supplier started selling commercial sodium batteries? Found it https://northvolt.com/articles/northvolt-sodium-ion/ https://northvolt.com/articles/northvolt-sodium-ion/
- conradev 3y ago
  Better cell design and better chemistry both contribute to safety, and I think the Blade’s primary innovation here is their cell design
  - hedora 3y ago
    From the wikipedia article, it's all about the form factor: > The space utilization of the battery pack is increased by over 50% compared to most conventional lithium iron phosphate block batteries. > BYD claims that, in the nail penetration test, the Blade Battery emitted no smoke or fire after being penetrated, and its surface temperature reached only 30 to 60 °C (86 to 140 °F). It is currently the only power battery in the world that can safely pass the test. Reducing volume by 33% and mostly eliminating fire risks are both huge wins, if true. Doing it in a standard form factor that can be reused across future vehicle platforms is an even bigger deal.
    - Animats 3y ago
      This is a lithium iron phosphate battery. Safer chemistry than lithium-ion, but heavier. There's a lot be said for lithium iron phosphate. Once we have millions of old, badly maintained electric cars on the road, it's better if they're not using a battery technology prone to fire. This is mostly a packaging and cooling innovation. Round cells are inefficient from a density standpoint, but the empty space between cylinders allows heat to escape. BYD's approach to electric cars in China is modest range and lots of charging stations. Average distance driven per day in the US is 60 km. Current BYD vehicles all have a range over 200km. Same niche as Chevrolet, or what Chevy used to be - a seller of basic transportation. It's a worry that, in the last few years, US manufacturers have gone way overboard on too much car per car, to the point that most American workers can't afford current vehicles.

The article is short on information on the battery itself but thankfully there is a Wikipedia entry for it: https://en.m.wikipedia.org/wiki/Blade_Battery https://en.m.wikipedia.org/wiki/Blade_Battery

catchnear4321 3y ago

thanks for the link, the “article” can’t even keep it on the rails for the intro. > The heart of any electric car is the battery. one way to look at it, sure. > It makes up around 40% of the value… well, that seems a bit arbitrary, but as not an expert myself, seems… fine. > …and we rely on it to keep us moving. well, sure, it is a required part of the car. we also rely on the wheels to keep us moving. > And yet we know very little about them. what in the actual…

tzs 3y ago
I remember in a solid state chemistry MOOC I took, from a professor who was a lithium battery researcher, the professor did mention in passing that we actually don't have a really good understanding of lithium batteries. Of course he was talking about a much lower level than you need to understand when it comes to actually using them. There are actually a lot of things we know how to deal with when it comes to engineering but have a poor grasp of the low level details. There was a great example in the Feynman Lectures where he says this about friction (Volume 1, section 12-2): > It is quite difficult to do accurate quantitative experiments in friction, and the laws of friction are still not analyzed very well, in spite of the enormous engineering value of an accurate analysis. Although the law F=μN is fairly accurate once the surfaces are standardized, the reason for this form of the law is not really understood. To show that the coefficient μ is nearly independent of velocity requires some delicate experimentation, because the apparent friction is much reduced if the lower surface vibrates very fast. When the experiment is done at very high speed, care must be taken that the objects do not vibrate relative to one another, since apparent decreases of the friction at high speed are often due to vibrations. At any rate, this friction law is another of those semiempirical laws that are not thoroughly understood, and in view of all the work that has been done it is surprising that more understanding of this phenomenon has not come about. At the present time, in fact, it is impossible even to estimate the coefficient of friction between two substances. That was written around 60 years ago. Anyone here happen to know if it still holds?
- user_7832 3y ago
  > That was written around 60 years ago. Anyone here happen to know if it still holds? Not really the same question but I attended a talk by some top tribologists at my uni and I asked them if friction really was independent of contact area (as F=μN would suggest), their reply was that it roughly was, but not really if you were very precise or varying parameters. It would appear that the equation is a good approximation, like classical Newtonian physics.
- _a_a_a_ 3y ago
  Apparently even solubility of compounds in various solvents is empirically derived because there's no reliable theoretical model of this in chemistry/physics. (AIUI anyway)
  - catchnear4321 3y ago
    not to get too leaky, and this is a bit dated, but… the math produces results that are understood but not, because the math is calculating with some implicit inclusions, and things get weird when you start explicitly including. the answers make sense, but not quite for the questions being asked. (but the answers are valid for a question, and more importantly, immediately useful for making dollars.) unfortunately the vagueness of this will likely irritate a doctor. it certainly did years ago.
- photochemsyn 3y ago
  At some point, scale-wise, friction problems become electrochemical rate problems, I suppose. See this recently published research article on lithium iron phosphate batteries, opening: > "Reaction rates at spatially heterogeneous, unstable interfaces are notoriously difficult to quantify, yet are essential in engineering many chemical systems, such as batteries and electrocatalysts..." https://www.nature.com/articles/s41586-023-06393-x https://www.nature.com/articles/s41586-023-06393-x It's a much harder problem than working with pure crystals or gas-phase molecules or similar, which makes sense, as a half-discharged battery is a very messy system at the molecular-atomic level. See also news story on the above article: > “We discovered at the nano scale that variation of the carbon coating thickness directly controls the rate, which is something you could never figure out if you didn't have all of this modeling and image analysis,” Bazant says. https://news.mit.edu/2023/pixel-analysis-yields-insights-lithium-ion-batteries-0913 https://news.mit.edu/2023/pixel-analysis-yields-insights-lit... So, the field seems to be progressing steadily - and more funding for fundamental solid-state materials science research makes sense, too.
joosters 3y ago
And: > But BYD is also a car maker in its own right Yeah, it's actually the largest electric car manufacturer in the whole world.
- eunos 3y ago
  BYD actually started as a battery maker.
- DoesntMatter22 3y ago
  Only if you consider a hybrid to be an electric car. Tesla is still bigger on BEVs
  - xbmcuser 3y ago
    They are expected to get ahead of Tesla end of this year.
    - DoesntMatter22 3y ago
      Most things I've seen say next year. Regardless, it's not a fact that they are the biggest yet.

deleted 3y ago

[deleted]

throwawaymaths 3y ago

Lfp chemistry is not that innovative -- it's in use in homes for sure and I think also tesla uses them. Given the breathlessness of the article I expected sodium batteries or something

Voultapher 3y ago
Wasn't there news recently that a big supplier started selling commercial sodium batteries? Found it https://northvolt.com/articles/northvolt-sodium-ion/ https://northvolt.com/articles/northvolt-sodium-ion/
conradev 3y ago
Better cell design and better chemistry both contribute to safety, and I think the Blade’s primary innovation here is their cell design
- hedora 3y ago
  From the wikipedia article, it's all about the form factor: > The space utilization of the battery pack is increased by over 50% compared to most conventional lithium iron phosphate block batteries. > BYD claims that, in the nail penetration test, the Blade Battery emitted no smoke or fire after being penetrated, and its surface temperature reached only 30 to 60 °C (86 to 140 °F). It is currently the only power battery in the world that can safely pass the test. Reducing volume by 33% and mostly eliminating fire risks are both huge wins, if true. Doing it in a standard form factor that can be reused across future vehicle platforms is an even bigger deal.
  - Animats 3y ago
    This is a lithium iron phosphate battery. Safer chemistry than lithium-ion, but heavier. There's a lot be said for lithium iron phosphate. Once we have millions of old, badly maintained electric cars on the road, it's better if they're not using a battery technology prone to fire. This is mostly a packaging and cooling innovation. Round cells are inefficient from a density standpoint, but the empty space between cylinders allows heat to escape. BYD's approach to electric cars in China is modest range and lots of charging stations. Average distance driven per day in the US is 60 km. Current BYD vehicles all have a range over 200km. Same niche as Chevrolet, or what Chevy used to be - a seller of basic transportation. It's a worry that, in the last few years, US manufacturers have gone way overboard on too much car per car, to the point that most American workers can't afford current vehicles.