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by DLwdTxdU6smHQA 1268 days ago
> Sodium ion batteries are less dense than lithium have a third of the range

Got a source for the "one third" part? According to [1] and [2] lithium ion is up to 265 Wh/kg and sodium ion has 160 Wh/kg.

[1] https://en.wikipedia.org/wiki/Lithium-ion_battery [2] https://cleantechnica.com/2021/07/30/catl-reveals-sodium-ion...

edited for clarity

3 comments

And keep in mind the Nickel-Cobalt Lithium ion chemistries are responsible for the "battery fire" Tesla stories.

So the Nickel-Cobalt batteries require a lot of cooling and safety systems. So this reduces the PACK level density to 60-70% from the lofty cell densities. So 240 wh/kg nickel cobalt chems drop to 160-180 at pack level.

LFP and Sodium Ion do not have such issues. They are inherently safer, so the Pack densities are potentially 90-95% of cell density with good design.

And to emphasize, CATL is putting into PRODUCTION in 2023 160 wh/kg sodium ion.

The other trick is to mix lithium and sodium ion cells in the same pack. So you do half at 160 wh/kg sodium, and half at 210 wh/kg LFP (LFP is hitting that in 2023 as well), then you get 185 wh/kg effectively.

IMO this Sodium Ion announcement marks when/where the barrier to electrifying 80-90% of consumer transportation AND allow India and China to get their own cars. It should just be a factory scaling issue now.

IMO this means the BEV drivetrain will be fundamentally cheaper than the ICE drivetrain by 30% in possibly 2-3 years. ICE cars will simply not be price competitive. The BEV will accelerate better, smoother, more reliable, be cheaper in maintenance, more torque/towing ability, AND it will be cheaper when you buy a new car.

That's for a 300 mile fast-charge electric car, with roadmaps to 400 mile with 200 wh/kg sodium ion.

Again, if sodium sulfur hits 2x to that (the research papers say 3-4x) in 5-10 years, that means the number of cells and cost to make the car and vehicle weight all drop that much more. You'll have 500-600 mile range cars that possibly cost half of what an ICE drivetrain would.

What is the energy density by volume?

Which is more important for cars? Weight or volume?

I would imagine that volume ultimately controls how much you can fit and that weight just negatively affects range of you have too much.

> lithium ion is up to 265 Wh/kg and sodium ion has 160 Wh/kg

This is what less dense means.

sure. but it seems one third of the range seems too pessimistic according to those numbers.
Sodium is about half the range with the older unimproved designs (new experimental ones are closer to parity with li-ion), it's better than the density number suggests because it's lower internal resistance - less steep discharge curve than li-ion.