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> Lithium iron phosphate batteries are very practical Unless you want to charge in negative temperatures > However, this battery faces range limitations Yes

> Lithium iron phosphate batteries are very practical Unless you want to charge in negative temperatures > However, this battery faces range limitations Yes they are less dense but plentiful for typical passenger car (and not so much for full sized trucks or even "mid-sized" US SUVs). > the issue of how to improve charging speed I think CATL demonstrated 1MW charging on these already. Definitely shipping 500kW charging (tho best measure is still average km/hr). > Solid-state batteries should be the next big thing Sodium will (great cold weather performance and even better charge rates), but it's less (vol) dense and prices won't reach LFPs for another 10-15 years (unless you believe hype, not actual analysts).

_aavaa_ 1y ago
> Unless you want to charge in negative temperatures Doesn’t the thermal management system of the battery packs handle this?
- butvacuum 1y ago
  Yes, the largest issue is that they heating isn't enabled unless it's charging or 'knows' it will be soon. Ps: the heating is increasingly heat pump based instead of resistive.
- dzhiurgis 1y ago
  It does, but it costs is complex, requires power and time. It's noticeable even in climates like NZ. There are coldgating stories about LFP. Some even reduce output and very low SOC and temperature, so you drive 60km/h in highway. Sodium is vastly superior here and CATL is not going to be giving it away for free.
sokka_h2otribe 1y ago
If it's suitable for sedans it's actually more suitable for SUVs. SUVs require less power per cubic feet of space. So there is more space available for them, even if they take more energy overall
- thebruce87m 1y ago
  There are variants of the Model Y with LFP batteries.
- pottertheotter 1y ago
  What? How does an SUV require less power per cf than a sedan? I would think that aero alone would always be worse for an SUV, making sedans more efficient.
  - AngryData 1y ago
    I think he means less power per total overall volume of the vehicle. SUVs are certainly less efficient per mile, but their power requirements don't scale linearly with volume so you have a lot more "extra" room to place batteries, even if it is still entirely within the frame. So you can get away with less space efficient batteries.
  - murderfs 1y ago
    Drag scales by frontal area (and the coefficient of drag tends to actually be lower on longer objects), so as long as the SUV is longer than a sedan, it'll tend to have less aerodynamic drag proportionally (rolling resistance scales with weight, though, so you still have to pay that cost).
  - Gibbon1 1y ago
    An observation is the amount of power needed is proportional to some log of size and weight.
- vincnetas 1y ago
  such strange unit of measurement. cubic feet of space. especially for civilian transport when most of the time no one uses that space. i mean most of the time its one person per car without any baggage. what's important is weight of the car. and i bet suv is heavier than sedans.
  - bluGill 1y ago
adgjlsfhk1 1y ago
I think it is fairly likely that sodium catches LFP in the ~5 year timeframe since sodium has a lot more promise for grid scale storage since it has no expensive materials.
- sroussey 1y ago
  When are the aluminum batteries coming?
- dzhiurgis 1y ago
  It still does have expensive materials (cheaper form of graphite), but a little bit less of it, namely lithium and there's something else I can't remember.
happosai 1y ago
> Unless you want to charge in negative temperatures LFP charging in cold has pretty much been solved by adding a heater to battery pack. > (Sodium-ion) prices won't reach LFPs for another 10-15 years (unless you believe hype, not actual analysts). Given CATL is scaling sodium-ion production to to GWh scale next year, it sounds like they are betting for a much shorter timeframe.
- dzhiurgis 1y ago
  > LFP charging in cold has pretty much been solved by adding a heater to battery pack. That's a hack, not a solution. > Given CATL is scaling sodium-ion production to to GWh scale next year, it sounds like they are betting for a much shorter timeframe. Wanna bet? LFP is ~1,000 GWh scale right now. GWh scale is 0.1%.
  - thecopy 1y ago
    >That's a hack, not a solution. Why do you say that? It sounds like a simple solution to me.
    - throwaway81523 1y ago
      It takes hours to heat a cold large pack til it's warm enough to charge. That's a drawback.
      - wood_spirit 1y ago
        All the EV owners in Scandinavia don’t have practical problems charging in winter at will.
        ponector 1y ago
        Also Scandinavia is not that cold. Their winters are quite warm, actually.
        dzhiurgis 1y ago
cameldrv 1y ago
I think CATL is promoting a hybrid pack of LFP and Sodium that would give you the cheapness and density of LFP, but with maybe 30% Sodium that you could use for a quick partial charge, and could also be used when the car is cold-soaked. Once you drive for a while, the whole pack gets warmed up and you can use the LFP.
- juliusceasar 1y ago
  Using lfp at low temp is not an issue. Charging is the problem.
  - vardump 1y ago
    > Charging is the problem. Which also occurs while driving, whenever you're decelerating.
  - dzhiurgis 1y ago
    > Using lfp at low temp is not an issue Bjorn managed to get couple cars in coldgate condition - so cold and such low SOC that it's just not enough power to heat up battery and now you going highway at 60 km/h. IDK, maybe just a software fix, maybe an edge case, but it can happen.
c2h5oh 1y ago
The small handful of sodium batteries that are currently available retail all seem to have rather bad roundtrip efficiency compared to LFP and voltage drop starting at a high state of charge. Also LFP prices dropped enough that shipping cost from China became a significant part of the price. This will be even more of a factor should the less energy dense sodium batteries ever reach the promised $30/kWh.
- PaulKeeble 1y ago
  One thing I hadn't groked about Sodium Ion was the enormous Voltage range leads to a bit of an issue when it comes to current. You have a 4x voltage from top to bottom of the battery and this also means your current is 4x as well for the same power output. This becomes a bit of an issue and it is part of the efficiency equation, not just externally to the battery where wires have to be much larger than LFP or LI but internally due to internal resistance.
  - namibj 1y ago
    Ehhh not really a problem unless you idolize 12/48 V style systems that aren't adequate for these modern chemistries (i.e., non-lead-acid based) that scale down effectively to single digit amp hours per cell. You can keep the current around a comfortable 20A at any pack size, just by increasing the voltage. Say 5Ah cells. At 1.5kV (the highest easily practical with mainstream transistors and sticking to the "simple" circuit designs), that's 7.5kWh per such battery string. That's a small home solar setup's entire battery.
- dzhiurgis 1y ago
  Sodium gravimetric density is same. Volumetric is worse. Shipping containers generally cost by volume, but given how dense batteries are I suspect this won't matter.
  - c2h5oh 1y ago
    I'd agree if you could stick them in the containers discharged, but you can't. This means that even safer chemistry like sodium battery is still hazardous cargo.
vardump 1y ago
> Unless you want to charge in negative temperatures I do all of my charging way above 0K. :-P
lazide 1y ago
The issue I’ve heard with sodium-ion is that the voltage curves make the power electronics much more expensive for a given efficiency/power level. [https://www.eevblog.com/forum/projects/sodium-ion-battery-evaluation/50/ https://www.eevblog.com/forum/projects/sodium-ion-battery-ev...] Lithium’s curve is nearly flat, which allows for a pretty easy consistent power production (albeit nearly impossible to tell state of charge!) since you only need to target a pretty narrow voltage band. Overall, that means sodium-ion has to be even cheaper to be competitive, and it makes even less sense in areas where power density matters like electric cars, as you’ll end up with far less power and/or needing much heavier motors and more expensive electronics to compensate when on the lower end of charge. I don’t want to think of what it would cost to do a 100kw buck-boost power supply that can handle +- 25% (or more!) voltage differences. In reality, I don’t think anyone would try.
infecto 1y ago
I am not sure honestly about the negative temperature. Sure it can be a problem in extreme colds but most of the world does not live in those climates.
UltraSane 1y ago
All modern EVs have tight thermal control of their battery packs to optimize lifespan and charging. They need to be cooled in the summer and heated in the winter.

_aavaa_ 1y ago

> Unless you want to charge in negative temperatures Doesn’t the thermal management system of the battery packs handle this?

butvacuum 1y ago
Yes, the largest issue is that they heating isn't enabled unless it's charging or 'knows' it will be soon. Ps: the heating is increasingly heat pump based instead of resistive.
dzhiurgis 1y ago
It does, but it costs is complex, requires power and time. It's noticeable even in climates like NZ. There are coldgating stories about LFP. Some even reduce output and very low SOC and temperature, so you drive 60km/h in highway. Sodium is vastly superior here and CATL is not going to be giving it away for free.

sokka_h2otribe 1y ago

If it's suitable for sedans it's actually more suitable for SUVs. SUVs require less power per cubic feet of space. So there is more space available for them, even if they take more energy overall

thebruce87m 1y ago
There are variants of the Model Y with LFP batteries.
pottertheotter 1y ago
What? How does an SUV require less power per cf than a sedan? I would think that aero alone would always be worse for an SUV, making sedans more efficient.
- AngryData 1y ago
  I think he means less power per total overall volume of the vehicle. SUVs are certainly less efficient per mile, but their power requirements don't scale linearly with volume so you have a lot more "extra" room to place batteries, even if it is still entirely within the frame. So you can get away with less space efficient batteries.
- murderfs 1y ago
  Drag scales by frontal area (and the coefficient of drag tends to actually be lower on longer objects), so as long as the SUV is longer than a sedan, it'll tend to have less aerodynamic drag proportionally (rolling resistance scales with weight, though, so you still have to pay that cost).
- Gibbon1 1y ago
  An observation is the amount of power needed is proportional to some log of size and weight.
vincnetas 1y ago
such strange unit of measurement. cubic feet of space. especially for civilian transport when most of the time no one uses that space. i mean most of the time its one person per car without any baggage. what's important is weight of the car. and i bet suv is heavier than sedans.
- bluGill 1y ago

adgjlsfhk1 1y ago

I think it is fairly likely that sodium catches LFP in the ~5 year timeframe since sodium has a lot more promise for grid scale storage since it has no expensive materials.

sroussey 1y ago
When are the aluminum batteries coming?
dzhiurgis 1y ago
It still does have expensive materials (cheaper form of graphite), but a little bit less of it, namely lithium and there's something else I can't remember.

happosai 1y ago

> Unless you want to charge in negative temperatures LFP charging in cold has pretty much been solved by adding a heater to battery pack. > (Sodium-ion) prices won't reach LFPs for another 10-15 years (unless you believe hype, not actual analysts). Given CATL is scaling sodium-ion production to to GWh scale next year, it sounds like they are betting for a much shorter timeframe.

dzhiurgis 1y ago
> LFP charging in cold has pretty much been solved by adding a heater to battery pack. That's a hack, not a solution. > Given CATL is scaling sodium-ion production to to GWh scale next year, it sounds like they are betting for a much shorter timeframe. Wanna bet? LFP is ~1,000 GWh scale right now. GWh scale is 0.1%.
- thecopy 1y ago
  >That's a hack, not a solution. Why do you say that? It sounds like a simple solution to me.
  - throwaway81523 1y ago
    It takes hours to heat a cold large pack til it's warm enough to charge. That's a drawback.
    - wood_spirit 1y ago
      All the EV owners in Scandinavia don’t have practical problems charging in winter at will.
      - ponector 1y ago
        Also Scandinavia is not that cold. Their winters are quite warm, actually.
      - dzhiurgis 1y ago

cameldrv 1y ago

I think CATL is promoting a hybrid pack of LFP and Sodium that would give you the cheapness and density of LFP, but with maybe 30% Sodium that you could use for a quick partial charge, and could also be used when the car is cold-soaked. Once you drive for a while, the whole pack gets warmed up and you can use the LFP.

juliusceasar 1y ago
Using lfp at low temp is not an issue. Charging is the problem.
- vardump 1y ago
  > Charging is the problem. Which also occurs while driving, whenever you're decelerating.
- dzhiurgis 1y ago
  > Using lfp at low temp is not an issue Bjorn managed to get couple cars in coldgate condition - so cold and such low SOC that it's just not enough power to heat up battery and now you going highway at 60 km/h. IDK, maybe just a software fix, maybe an edge case, but it can happen.

c2h5oh 1y ago

The small handful of sodium batteries that are currently available retail all seem to have rather bad roundtrip efficiency compared to LFP and voltage drop starting at a high state of charge. Also LFP prices dropped enough that shipping cost from China became a significant part of the price. This will be even more of a factor should the less energy dense sodium batteries ever reach the promised $30/kWh.

PaulKeeble 1y ago
One thing I hadn't groked about Sodium Ion was the enormous Voltage range leads to a bit of an issue when it comes to current. You have a 4x voltage from top to bottom of the battery and this also means your current is 4x as well for the same power output. This becomes a bit of an issue and it is part of the efficiency equation, not just externally to the battery where wires have to be much larger than LFP or LI but internally due to internal resistance.
- namibj 1y ago
  Ehhh not really a problem unless you idolize 12/48 V style systems that aren't adequate for these modern chemistries (i.e., non-lead-acid based) that scale down effectively to single digit amp hours per cell. You can keep the current around a comfortable 20A at any pack size, just by increasing the voltage. Say 5Ah cells. At 1.5kV (the highest easily practical with mainstream transistors and sticking to the "simple" circuit designs), that's 7.5kWh per such battery string. That's a small home solar setup's entire battery.
dzhiurgis 1y ago
Sodium gravimetric density is same. Volumetric is worse. Shipping containers generally cost by volume, but given how dense batteries are I suspect this won't matter.
- c2h5oh 1y ago
  I'd agree if you could stick them in the containers discharged, but you can't. This means that even safer chemistry like sodium battery is still hazardous cargo.

vardump 1y ago

> Unless you want to charge in negative temperatures I do all of my charging way above 0K. :-P

lazide 1y ago

The issue I’ve heard with sodium-ion is that the voltage curves make the power electronics much more expensive for a given efficiency/power level. [https://www.eevblog.com/forum/projects/sodium-ion-battery-evaluation/50/ https://www.eevblog.com/forum/projects/sodium-ion-battery-ev...] Lithium’s curve is nearly flat, which allows for a pretty easy consistent power production (albeit nearly impossible to tell state of charge!) since you only need to target a pretty narrow voltage band. Overall, that means sodium-ion has to be even cheaper to be competitive, and it makes even less sense in areas where power density matters like electric cars, as you’ll end up with far less power and/or needing much heavier motors and more expensive electronics to compensate when on the lower end of charge. I don’t want to think of what it would cost to do a 100kw buck-boost power supply that can handle +- 25% (or more!) voltage differences. In reality, I don’t think anyone would try.

infecto 1y ago

I am not sure honestly about the negative temperature. Sure it can be a problem in extreme colds but most of the world does not live in those climates.

UltraSane 1y ago

All modern EVs have tight thermal control of their battery packs to optimize lifespan and charging. They need to be cooled in the summer and heated in the winter.