5 ms·

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.
  - ramesh31 3y ago
    >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. Things like the Nissan Leaf have been widely available in the US for nearly a decade now, with battery sizes from 20-40kWh. There's a market for it, but it's niche. The reality is just that EVs will never truly become mainstream in the US until there's a >60kWh budget vehicle that sells out the door under $25k. The distances are simply too much for anything less to be viable for people outside of a major metro area.
    - lnsru 3y ago
      I share your opinion. Everything <60 kWh has no real winter range. 60 kWh battery brings me 150 miles in winter (Autobahn in Germany, not saving energy) since the regular battery shouldn’t be charged to 100% and discharged bellow 10%. That’s 2 days of commuting without charging for me.
      - Tagbert 3y ago
        I believe that is one of the benefit of the LFP chemistry that it is not harmed by sustained charges to 100%. That should help offset the range downside sometimes listed for LFP batteries.
        uxp100 3y ago
        However, IIRC it has other problems in cold weather. With charging, I think? I know I’ve seen reports that regenerative braking is essentially completely disabled while the LFP batteries are cold.
      - Turskarama 3y ago
        But if you charge every day (at home) you still wouldn't ever need to supercharge, so it's still enough range for 95% of driving.
      - idontwantthis 3y ago
        I think if it cost less than $20k new it would be the perfect second car.
throwawaymaths 3y ago
Article still called out chemistry.

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.
- ramesh31 3y ago
  >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. Things like the Nissan Leaf have been widely available in the US for nearly a decade now, with battery sizes from 20-40kWh. There's a market for it, but it's niche. The reality is just that EVs will never truly become mainstream in the US until there's a >60kWh budget vehicle that sells out the door under $25k. The distances are simply too much for anything less to be viable for people outside of a major metro area.
  - lnsru 3y ago
    I share your opinion. Everything <60 kWh has no real winter range. 60 kWh battery brings me 150 miles in winter (Autobahn in Germany, not saving energy) since the regular battery shouldn’t be charged to 100% and discharged bellow 10%. That’s 2 days of commuting without charging for me.
    - Tagbert 3y ago
      I believe that is one of the benefit of the LFP chemistry that it is not harmed by sustained charges to 100%. That should help offset the range downside sometimes listed for LFP batteries.
      - uxp100 3y ago
        However, IIRC it has other problems in cold weather. With charging, I think? I know I’ve seen reports that regenerative braking is essentially completely disabled while the LFP batteries are cold.
    - Turskarama 3y ago
      But if you charge every day (at home) you still wouldn't ever need to supercharge, so it's still enough range for 95% of driving.
    - idontwantthis 3y ago
      I think if it cost less than $20k new it would be the perfect second car.

throwawaymaths 3y ago

Article still called out chemistry.