I’ve been hearing about these for a few years now. Huge if they work out at a large scale.
Is this the next big thing? Na.
Na.
Sodium, not natrium.
I have a surprise for you…
Maybe they will make a potassium battery, K?
Maybe, but I want to see Uranium batteries go mainstream, how 'bout U?
I was hoping science would’ve gotten us to a tri lanthanside by now https://youtu.be/D8fHatctfRo
Sodium-Ion is already in production at CATL. Been for about half a year if I recall. It’s slightly less dense than LFP but it’s cheaper and promises to get cheaper yet.
And loads of charge cycles IIRC.
but it’s cheaper
and way less dangerous.
You’re right, they were making a pun about sodium’s chemical symbol.
Not who you replied to, but thanks for explaining! I saw the /j but still didn’t get it. I wasn’t a good chemistry student…
Commercialize it? Oh this one could be real
Its already way past its “real” point. Just hasnt really made it to Europe fully. China is already mass producing them for everything.
Any info about energy density?
I think they are testing Unigrid battery model 72173207 (terrible name). That is their 210Ah NCO prismatic cells.
I found this spec sheet. No definitive metrics, but someone else could do the napkin math.
CATL’s that went into mass prod sometime ago are 175Wh/kg.
According to Wikipedia:
Looks like power to weight it much higher, while energy per volume and energy per mass is comparable to existing lithium ion batteries.
idk about that, the regularly cited reason Na-ion batteries are mainly being looked at for grid storage rather than vehicle applications is their bad Wh/l and W/kg numbers compared to Li-ion. the table in the Na-ion article seems to use “1000W/kg” without a source, and it shows lithium as being about a third of that even though the Li-ion article quotes figures up to 10kW/kg.
seems the editors of the two articles aren’t cross-checking eachother.
W/kilo? Isn’t there a h missing or something?
one is energy density, the other is power density.
Aah, makes sense. I have seen soo many people confounding power and energy I thought it was the same here, my excuses.
ion. the table in the Na-ion article seems to use “1000W/kg” without a source, and it shows lithium as being about a third of that even though the Li-ion article quotes figures up to 10kW/kg.
seems the editors of the two articles aren’t cross-checking eachother.
No, it seems like you have zero idea what you are talking about and are confusing W/kg with Wh/kg, which are very different metrics
The “1000W/kg” figure appears to be from Wikipedia, which claims https://www.idtechex.com/en/research-article/sodium-ion-batteries-will-diversify-the-energy-storage-industry/30405 as a source. Wikipedia has the information in a table flagged as “Needs update”.
Anyway, most of the lithium-ion chemistry variations drop off relatively fast in capacity over repeated charge cycles (the exception being LiFePo4). If the sodium-ion chemistry is better that way, and drops off less in the cold, it’s still worth exploring for vehicle use even if the energy density is a little lower.
from other comments it seems the energy density of batteries currently on the market is about 2/3rds that of lithium cells.
there’s also the asymmetry to worry about: with a max discharge rate of 8C but a charge rate of 3C there could potentially be limits on regen braking. if i’m understanding it correctly, sodium cells degrade quickly at higher charge rates.
Just put condensers/a small lithium break battery in.
i think bmw was working on something like that.
Googling says 175 whr/kg for catls sodium car battery that’s already in production cars vs 270 whr/kg for Tesla’s lithium.
according to their product page, the charge rate for a single cell seems to max out at 3C, which could be a pretty big obstacle to grid-scale deployment. unless that’s a problem that can be fixed with a different arrangement; i’m not too up on how to build batteries.
which could be a pretty big obstacle to grid-scale deployment.
Well, on a grid scale if you’ve got a 100MWh battery and you want to charge it at 3C, then you’re looking to find a spare 300MW out on the grid somewhere for 20 minutes.
That’s not impossible, but you’ll buy that 100MWh a lot cheaper if you’re willing to get it over the course of a few hours. For example, buying power in the middle of the day when there’s excess solar, to then drop it back into the grid in a one hour burst during peak times in the evening for 10 times the price.
That kind of thing is where the battery will make the most profit, so slow charge rates don’t really matter.
i think the big issue is asymmetry. they charge at 3C, but they discharge at 8C. so you need the significantly overbuild.
I assume 3C is a 20 minute charge?
1 C is defined relative to 1 hour for full discharge and 3 C means a 3x faster discharge rate (full capacity can safely be discharged in 1/3 hour, or you can discharge 3 cells sequentially in an hour). Good lithium cells tend to be above 5C, can reach 10C for peak load or if cooled.
For a large enough battery it doesn’t really matter, but for dense portable ones a lower C rating means you have to discharge from more cells simultaneously to maintain a given output. That makes it more complicated, and you have less headroom to the battery’s maximum Watt output if you need to accelerate a car hard suddenly.
NMC cells typically operate around 1-2C and LFP cells 1-3C. If you want to achieve 10C then you’re probably gonna have to look at LTO cells. All of these are lithium-ion chemistries but they each have different characteristics.
(for context most my knowledge of these cells are from single cell +5000 lumen flashlights :)
The comment I am responding to is about charge rate, not discharge rate
For most batteries that’s the exact same rate
Sodium ion batteries are asymmetrical, pushing charge current hard can drive the anode negative enough to deposit metallic sodium causing formation of dendrites which destroys the battery
Kind of, yes. But more importantly, it also means it can only push enough power to run at 3c. And that’s probably not for the full charge of the battery.
So a 100 amp hour battery rated at 3c can push out 300 amps. Which also means that if the grid needs a short spike in power, it might be limited.
It shouldn’t be too hard to get a 15c LiPo battery, which could push 5x as much energy at peak demand.
You’d probably kill the battery if you charged it from 0-100 at 15c, but for short bursts of charging and discharging, it should handle it just fine.
The comment I am replying to is discussing charge rate of 3C, not discharge rate
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