cross-posted from: https://lemmy.zip/post/48958993
energy density of 175 Wh/kg
CATL explained that sodium-ion batteries have slightly lower energy density than lithium-ion batteries but provide distinct advantages in low-temperature performance, carbon footprint, and safety.
These things are a game changer. For a car, you don’t need the energy density of li-ion. They don’t fly, they don’t get carried around by people.
They are significantly safer than lithium-ion. They don’t burst into flames if the container is breached. They don’t build up hydrogen bubbles. I believe they have a higher cycle lifespan. And they don’t degrade when fully charged or discharged like lithium do.
They are also much more environmentally friendly to develop and cheaper to produce (which mean they will never be allowed into the US because of Elon Musk).
One downside is that compared to other solutions this is a really heavy battery afaik, but honestly having no fire hazards and way better lifespan totally worths this tradeoff
I really hate how all these headlines give battery capacity as a distance, as though that was a meaningful measure or allowed comparing different technologies.
kWh/kg female dogs !
It’s a ballpark number. It says to me “competitive with LiIon on capacity though not beating it yet.”
It’s not though. Range is determined by how much battery is in a car, I could build a car with 500km worth of Ni-MH but it would be mostly battery.
Does the same car with 500km worth of lithium batteries have more or less trunk space than 500km of these batteries? I have no idea. I do know the sodium batteries will weigh a bit more, because the article actually gives Wh/kg - and that makes sense since sodium the metal is denser than lithium, but the headline is meaningless.
But it’s all stupid people and marketing people understand more=better cheaper=better. I think it’s why ev adoption has been so poor, questions I get asked are what’s the range like? Doesn’t it take forever to charge? And aren’t they really expensive?
They do the same thing with grid storage batteries and I hate it. “Our battery lasts 20 hours!” Think it was a better unit like watts per 4 hours but media and marketing mess with it.
People understand time.
People have no fucking idea how much their crap uses. So giving the watthour is literally pointless.
It’s a nice statistic to have.
But for cars, giving a cars range in watthours is like saying the road trip is 8.3 gallons of gas.
JUST TELL ME HOW LONG IT WILL TAKE TO GET THERE OR HOW FAR IT IS.
I think the issue in this case is that the range of this specific car and battery doesn’t convey the impact of the battery innovation. If they gave an example of the range with that car and battery size using current battery tech to demonstrate the improvement, I think that would be more helpful.
They are cheaper and the low temperature performance is better than LFP, but the round trip efficiency is less than LFP.
Question is… How much cheaper…
LFP is almost at the price point we could all have a freezer sized battery pack in our house, drastically changing the grid, and allowing a place for all that wind/solar to store energy.
If Sodium is a fair chunk cheaper, then it will totally be worth buying a house battery pack. Buying energy on the cheap at certain times of day, and using the battery when energy prices are high.
Why wouldn’t the grid do this on an industrial scale and remove any off peak discounts?
Potentially 1/10th the price according to this video I stumbled on about it a couple of days ago!
That video makes it sound exciting but I’ve heard Matt hypes things up more than they should be
Plus market dynamics means that even if it’s 90% cheaper to make, they will only reduce the price compared to LFP by 10% to maximize profits.
They also have better thermal stability, so less risk of uncontrolled fires.
AFAIK, LFP thermal runaway can’t start fires. NMC or other lithium chemistries can and they scare me, but LFPs are pretty damn safe. That being said, I’m still stoked for sodium chemistries to be developed. If the round trip efficiency issues can be solved, then I think it’ll be a great solution for residential power storage.
What does round trip efficiency mean here?
How much energy you get out of a full charge, divided by how much energy you need to fully charge it. It’s around the 90% mark for lithium based tech, no idea what it is for these sodium ones
As long as the efficiency is outweighed by price, it could move us in the right direction. Hopefully we can pick up the efficiency in time. These would also be good for my future load-shifting (charge during off peak, low carbon electricity) and maybe solar system at home.
“slightly lower” == 2/3rds, apparently. the model 3’s pack is 250Wh/kg. also, 500km range in what? the only way you could fit an equal-range battery in a contemporary compact vehicle like the model 3 would be if it had almost double the density of Li-ion.
Sodium itself Is nearly double the density of Lithium. I don’t know how much that affects the whole pack, but it’s gotta be something.
The model 3 is not a compact vehicle…it’s a regular size sedan.
it is apparently D-segment, yeah. i have a C-seg car and have found the model 3 to be very similar in size, but maybe that’s just a matter of the height making it look smaller.
