A sodium-ion portable power bank comes to market | Hacker News Reader

A sodium-ion portable power bank comes to market

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49 pointsnamanyayg25 comments

Seems like the painful point of sodium-ion is mainly the weight/size (per unit of power)...

Is that something that can catch up, or is it simply a density issue that can't be terribly optimized?

Right now it looks like it takes ~75% more space for the equivalent power... after two decades like Lithium-ion has had, can that reach current density/size for the same power, or will it hit a cap?

Still nice to see a battery tech hit the market.

The big deal is it's made out of sodium. Anyone with access to sea water (which is full of Na + Cl) can make these batteries, and it's unlikely we're going to run out of sea water in the near future, or even next 3 billion years.

Sodium batteries will probably be the go-to for grid scale battery in (wild guess) ten years and some of the ultra-cheap electronics. Sodium, Li-ion and lifepo4 all have significant overlap in the 2.5-3.7v range so there's a lot of potential for compatibility/interoperability

Compare with lithium batteries, which currently there's only a handful of high quality lithium deposits that are convenient to be mined

> it's unlikely we're going to run out of sea water in the near future, or even next 3 billion years.

I hate to break it to you like this, but the oceans will evaporate in about a billion years.

https://en.wikipedia.org/wiki/Future_of_Earth

We should still have the sodium, though.

Well, ozone hole was supposed to increase and engulf the whole planet, but... I'm sure this is a long enough time to avoid predictions.

Sometimes we even treat sodium chloride as leftover byproduct[1]. "[...]as of August 2016, it covered 98 hectares (240 acres) and contained approximately 201 million tonnes of salt, with another 900 tonnes being added every hour and 7.2 million tonnes a year." 7 Megatonnes of unused salt a year. The problem with using sodium from that mountain - what to do with leftover chlorine.

[1] https://en.wikipedia.org/wiki/Monte_Kali

Sodium is huge and heavy compared to Lithium, at almost quadruple everything, and then it has 3 valence rings instead of 2 compared to lithium. The density issue is very much limited by this, in a physical sense.

Lithium on paper has better energy density because of where the element sits on the periodic table. Sodium is pretty close though. So, it's unlikely to push lithium out of the market for a lot of use cases.

Both chemistries are likely to continue to improve. And sodium ion is still pretty new. There might be some solid state batteries based on sodium ion at some point. Lithium ion solid state batteries are much closer to market ready (multiple manufacturers have announced product roll outs over the next few years).

For a lot of use cases, cost and safety might be more important than energy density. There are a lot of different chemistries at this point.

This device is a bit on the heavy side but not overly so. 350 grams is not that heavy. Probably price and longevity are more decisive factors for people that would buy this. And the safety is a nice bonus.

>Lithium on paper has better energy density because of where the element sits on the periodic table. Sodium is pretty close though. So, it's unlikely to push lithium out of the market for a lot of use cases.

With less thermal management problems, maybe the packaging of sodium-based batteries may end up turning better (lighter, more compact) than lithium ones. That is a way how in theory it is worse, but in practice it isn't so.

I don't think sodium has a bright future - it's a 3x bigger ion for storing the same amount of charge, which makes it heavier, and the ion's bigger, leading to more deformation and damage to the separator, and lower cycle count, while the whole battery's also heavier.

Lithium's come down in price enough that its no longer the primary driver of battery cost, so I wouldn't bet on Sodium.

But I think they’re inherently safer? I wouldn’t be surprised if we see some sort of wide ban of lithium batteries on planes at some point. Maybe sodium ones would be allowed and they’d have that specific utility. “AirSafe Power Certified”

Lithium batteries are already mostly banned on planes. The TSA does not allow lithium batteries in checked luggage and limits the size of lithium batteries in carry on luggage to 100Wh or 2g of lithium. This is the reason that it's very difficult to find a laptop with a battery size larger than 99Wh.

> The TSA does not allow lithium batteries in checked luggage

It's not a complete ban. See https://www.tsa.gov/travel/security-screening/whatcanibring/... and https://www.faa.gov/hazmat/packsafe/portable-electronic-devi... and especially this bit:

> When portable electronic devices powered by lithium batteries are in checked baggage, they must be completely powered off and protected to prevent unintentional activation or damage.

Spare batteries and power banks are strictly required to be carry-on and not in checked baggage, but you can put a laptop in checked baggage as long as it's powered off.

They aren’t close to being banned. They’re explicitly allowed with a defined size/capacity.

Even after a recent fire, South Korea just tightened the rules (eg no charging on flights) But they’re still allowed.

https://amp.abc.net.au/article/105063388

I think we might just have “AirSafe” certified batteries allowed only at some point. Or TSA approved ones. The ban would make a hell of a lot more sense than liquids

> This is the reason that it's very difficult to find a laptop with a battery size larger than 99Wh.

I remember when laptops used to have pluggable batteries. You could even take one extra with you, or buy one extended battery with more capacity.

Surely there's applications where weight doesn't matter much, like home energy storage for solar setups?

For home storage, the reduced endurance will be probably what sinks Sodium, imo

> Elecom says the Na Plus can operate in temperatures ranging from around -30 to 122 degrees Fahrenheit

Nice perk. 122 F doesn't sound like a ton.

45W for a small-ish pack like this is pretty power dense. I wonder if it can charge at 45W too?

5000 cycles is comparable to LFP, quite decent.

Others have already discussed, yes, it's not nearly as energy dense as li-po. It feels.lile it performs closer to LFP, with high currents, better temp flexibility, good cycle.count, high safety. Would be neat to have the exact energy density figures for all three.

Expect sodium-ion to overwhelm the electric scooter and ebike markets. They're the trifecta of cheap, safe, and reliable. Size will come down as they mature mass production.

They're a step beyond LFP on those dimensions. Is LFP common in e-bikes yet?

I recently searched for LFP bikes and found basically none.

Would love to have one though as keeping one on a boat I would only feel safe with a high quality LFP at the capacity needed.

Their weight make them uncommon for bikes, and more common for boats and camper vans (places with high temperature fluctuations, intermittent power recharge through solar panels, need for reliability, and where you don't want the slightest chance to be burned to death in your sleep).

Boat stability and seaworthiness is often improved by well-placed ballast - those batteries' weight is not a drawback in that use case. With camper vans, they can be placed in a low central position too.

E-bike batteries are a major cause of domestic fires.

It's the largest lithium battery that gets charged inside the home, and also likely to be physically damaged (accidents, kerbs, even things like water ingress or corrosion) and likely to be poor quality or without proper type testing (lots of random manufacturers), and even likely be modified etc (people like to tinker with their bikes).

Weight is less of a problem on an e-bike than on a regular bike (even on regular bikes, weight is really overemphasised).

I'd be much happier if they were all LFP.

LiFePo are really heavy though, too heavy for practicality for bikes.

Let's hope that sodium-ion can fill that niche.

I still think home energy storage systems make the most sense to start.

Vehicles are hard because energy density matters a lot there.

Home storage also benefits a ton from cheap, safe and reliable storage (it's why LFP is so popular for a lot of systems at the moment) and they are incredibly flexible on energy density - the difference between a big box sitting outside against a wall and a slightly bigger/heavier big box sitting outside against a wall is mostly negligible.

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LFP is the first system I would actually install from a maintenance/safety/cost standpoint. But while they're good, they can still fail and catch fire. I'd happily have a bigger box against my wall if it means a cheaper & safer battery.

Will we get dashcams with batteries which dont die in the heat?

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