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Energy density and availability of materials. Li-S ballpark is 550 Wh/kg while conventional lithium-ion is around 200 Wh/kg. Using nickel, cobalt, and other exp

Energy density and availability of materials. Li-S ballpark is 550 Wh/kg while conventional lithium-ion is around 200 Wh/kg. Using nickel, cobalt, and other expensive metals is not scalable.

freemint 4y ago
Newer Battery Electric vehicle of similar size are not really much heavier then combustion cars of the same size. That boost in weight savings (and poorer duty cycles) would make such more sense for airplanes than cars. The Nickel and Cobalt parts have been declining for decades and are low percentages of *-ode material, especially in cars which are no volume constrained. Only smartphone batteries or similar appliances have high amounts of those. In fact there some EVs which have less cobalt then normal cars because cobalt steel is used in many parts of the motor and transmission.
- kdbeall_ 4y ago
  Yeah, LFP is arguably good enough for 80% of all EVs is my guess. Arguably it is also good enough for energy storage as well. However, for EVs, LFP doesn't have as high energy density. Something like 70% of all cobalt is mined in the DRC. I still think there will need to be more advanced and affordable battery chemistries before there is ubiquitous battery energy storage and EV adoption. This is why something like Li-S is the holy grail of batteries.
  - freemint 4y ago
    LFP doesn't have as high cells densities, however on a packaging level (due to their higher stability) next gen LFP seems to be on par with this gen Li-Ion. Also quick charging and cold resistance of LFP is a big improvement. I would rather see Li-S be used in planes where inspections are common unlike cars. For grid storage neither is ideal, as you really want to decouple (dis)charging from capacity. Subterranean normal pressure hydrogen storage (using geological structures like salt caves) or flow batteries seem more promising for that reason.
    - kdbeall_ 4y ago
      Vanadium redox flow batteries have energy densities of ~10–20 Wh/kg. But for grid storage I think even sodium-ion batteries would be a better candidate. Those have energy densities of ~150 Wh/kg. Vanadium is mostly produced as a byproduct of mining magnetite iron ore deposits. So, sodium-ion is less dependent on the output of handful of mines globally. Having a hydrogen economy is overall pretty inefficient. I think it's largely a dead end. We do not need multi-year energy storage. Seasonal storage is needed at most. Lithium-ion batteries have self-discharge rates of around 2% per month. Even if the batteries lose ~10% over a few months that's an acceptable loss and is superior to the inefficiencies inherent in hydrogen production via electrolysis and the subsequent use of stored hydrogen via fuel-cells — which require platinum-group metals.

Energy density and availability of materials. Li-S ballpark is 550 Wh/kg while conventional lithium-ion is around 200 Wh/kg. Using nickel, cobalt, and other expensive metals is not scalable.

freemint 4y ago

Newer Battery Electric vehicle of similar size are not really much heavier then combustion cars of the same size. That boost in weight savings (and poorer duty cycles) would make such more sense for airplanes than cars. The Nickel and Cobalt parts have been declining for decades and are low percentages of *-ode material, especially in cars which are no volume constrained. Only smartphone batteries or similar appliances have high amounts of those. In fact there some EVs which have less cobalt then normal cars because cobalt steel is used in many parts of the motor and transmission.

kdbeall_ 4y ago
Yeah, LFP is arguably good enough for 80% of all EVs is my guess. Arguably it is also good enough for energy storage as well. However, for EVs, LFP doesn't have as high energy density. Something like 70% of all cobalt is mined in the DRC. I still think there will need to be more advanced and affordable battery chemistries before there is ubiquitous battery energy storage and EV adoption. This is why something like Li-S is the holy grail of batteries.
- freemint 4y ago
  LFP doesn't have as high cells densities, however on a packaging level (due to their higher stability) next gen LFP seems to be on par with this gen Li-Ion. Also quick charging and cold resistance of LFP is a big improvement. I would rather see Li-S be used in planes where inspections are common unlike cars. For grid storage neither is ideal, as you really want to decouple (dis)charging from capacity. Subterranean normal pressure hydrogen storage (using geological structures like salt caves) or flow batteries seem more promising for that reason.
  - kdbeall_ 4y ago
    Vanadium redox flow batteries have energy densities of ~10–20 Wh/kg. But for grid storage I think even sodium-ion batteries would be a better candidate. Those have energy densities of ~150 Wh/kg. Vanadium is mostly produced as a byproduct of mining magnetite iron ore deposits. So, sodium-ion is less dependent on the output of handful of mines globally. Having a hydrogen economy is overall pretty inefficient. I think it's largely a dead end. We do not need multi-year energy storage. Seasonal storage is needed at most. Lithium-ion batteries have self-discharge rates of around 2% per month. Even if the batteries lose ~10% over a few months that's an acceptable loss and is superior to the inefficiencies inherent in hydrogen production via electrolysis and the subsequent use of stored hydrogen via fuel-cells — which require platinum-group metals.