A novel solid, rechargeable air battery

https://www.waseda.jp/top/en/news/78001

by rustoo • 3 years ago

59 53 3 years ago

skykooler• 3 years ago

While the discharge capacity of SSAB-PDBM reduced to 44% after 30 cycles, by increasing the proton-conductive polymer content of the negative electrode, the researchers could significantly improve it to 78%.

That's still a 22% drop in capacity after only 30 charge cycles; this system has a long way to go before becoming a practical battery.

fbdab103• 3 years ago

While probably not ideal for a phone or car, it could still have its uses. So long as it stabilizes at that 70%+ region, that is not potentially a deal-braker for grid installations. Which is an optimization of installation cost, maintenance, longevity, operating temperature/pressure requirements, charge/discharge rates, etc.

DennisP2• 3 years ago

They didn't say it stabilizes, though. You'd think they'd mention that if it did.

idontwantthis• 3 years ago

If it stabilized then it would just be 30% heavier. I doubt it stabilizes.

trompetenaccoun• 3 years ago

Depends one the cost and environmental impact. I don't know anything about the compounds they used and anyway they're still experimental and could be replaced by others. But in stationary settings where size isn't an issue they can lose substantial capacity upfront and still be viable if they can be cheaply produced and don't involve complicated steps like in lithium mining for example.

HPsquared5• 3 years ago

Flow batteries are better suited for stationary applications, I think. Liquids lend themselves to large-scale processing.

scandum• 3 years ago

the coulombic efficiency of SSAB-PDBM was 84% at 4 C rate, which gradually decreased to 66% at 101 C rate.

Lithium batteries are over 95% efficient, so a long way indeed. Since the battery contains water, I assume it doesn't work below 0 C.

elcritch• 3 years ago

It's a solid electrolyte battery, not water electrolyte based.

tzs• 3 years ago

I don't think 4 C and 101 C are referring to temperature. In battery charging/discharging 1 C is the current you would get if you could discharge a fully charged battery in 1 hour at a constant current.

If a battery's stated capacity is say 2000 mAh then 1 C for that battery is 2000 mA.

Recommended discharge and charge (if applicable) rates are usually specified in terms of C. For example the usual recommendations for charging Panasonic Eneloop batteries is 0.5 - 1 C. So if you are charging an AA which has about 2000 mAh capacity that would be 1000 - 2000 mA, but if you were charging an AAA which has something like 900 mAh capacity that would be 450 - 900 mA.

dtx1• 3 years ago

Just for Context thats roughly an order of magnitude worse than current lithium ion and almost 2 orders of magnitude worse than lithium iron phosphate.

simondotau2• 3 years ago

It seems there's news of a battery breakthrough every week. I've learned to temper expectations, because so many "breakthroughs" turn out to be dead ends. Because it's not enough for a battery to be incredibly light, or made of abundant materials, or last for ten thousand cycles. It needs to be good any many things and at least okay at most things.

E.g.—

• How much capacity per dollar?

• How much capacity per kilogram?

• How much capacity per litre?

• How quickly can it be charged?

• How quickly can it be discharged?

• How much energy is lost between charging and discharging?

• How predisposed is it to catching fire?

• How available are the materials needed to manufacture it?

• How available are the tools/skills required to manufacture it?

• How resilient is it to mechanical stress, e.g. vibration?

• How much does performance degrade per cycle?

• How much does performance degrade when stored at a high state of charge?

• How much does performance degrade when stored at a low state of charge?

• How much does performance drop at high temperatures?

• How much does performance drop at low temperatures?

• How well can it be recycled at end-of-life?

A sufficiently bad answer for any one of these could utterly exclude it from contention in many usages. A battery which scores well on everything except mechanical resilience is a non-starter for EVs, for example. On the other hand, a battery that's no good for EVs might be great for stationary storage.

I'm only a layperson and this list is the result of just a few minutes thought. I'm sure someone with more familiarity with the subject could double this list. But the point is, when you daydream about some hypothetical future battery tech, you need to appreciate just how well today's lithium chemistries score in so many areas.

HPsquared5• 3 years ago

There's probably a Nobel prize in it for anyone who can significantly improve on lithium ion. It's a tall order. Many have tried, many have failed. Eventually someone might succeed.

Turskarama5• 3 years ago

If someone managed to improve on it in every metric then yes, absolutely.

The thing is though that you don't have to beat it on every metric to be useful, you have to be _good enough_ on every metric and then really good on one or two.

For example, it's absolutely fine for a battery to weight five times as much if it doesn't need to be portable. Five times as heavy but half the cost per MWh? That's great for grid storage!

Twice as expensive and non rechargeable but 4 times the capacity (per unit volume)? Great for pacemakers!

It's all about finding the right niche.

tyho• 3 years ago

I doubt it will happen this decade. lithium ion is Goodenough.

uoaei2• 3 years ago

A lot of the capacity we'll end up needing will be stationary in nature, where weight isn't nearly as important as energy density, stability, charge/discharge rates, etc. Such installations can be climate-controlled using energy stored in those batteries. Some of the more creative designs end up making about half of the questions you listed more or less irrelevant so that we can focus exclusively on electrical performance.

sparrowInHand• 3 years ago

But the mobile/car devices space is the gatekeeper. Nobody produces batteries without extensive testing and extensive testing happens in fast lifed industries. Same why powerwalls were not a thing, before laptops phones pushed liIon-Batterys through this barrier.

laserbeam2• 3 years ago

And the problem with the article is it doesn't discuss virtually any of those. How are we publishing papers on batteries in 2023 without making these things obvious in the abstract?

During the first 5 seconds of reading a publication on batteries I should be able to answer at least 1 or 2 of those questions.

DrScientist• 3 years ago

Eh? Did you read it?

Note the article is a summary of the research, not the research itself.

JumpCrisscross• 3 years ago

Is there a standard flowchart of tests for battery researchers, or those evaluating novel battery chemistries? For example, first test energy density, then BOM without economies of scale, et cetera.

bartislartfast• 3 years ago

I would love to see a grid of all these values for all the latest battery technologies, to see what's leading the field between solid, sodium, aluminium, Sulfur Selenium, iron, etc

sholladay• 3 years ago

Meanwhile, lithium-ion is improving remarkably each year.

https://insideevs.com/news/581729/volumetric-energy-density-...

doctor_eval• 3 years ago

That graph is a bit deceptive; the X axis is not linear, but instead shows years 2008, 2010, 2013, 2017 and 2020.

DannyBee2• 3 years ago

It's wrong anyway. Even back in 2008, it was more than 50 watt hours per liter.

The graph is taken straight from the DOE website, here:

https://www.energy.gov/eere/vehicles/articles/fotw-1234-apri....

Without attribution of course. They just re cited the paper the DOE cites.

The paper has no such graph:

https://www.osti.gov/pages/servlets/purl/1842609

The graph is clearly wrong.

_hypx2• 3 years ago

That graph is plainly wrong. The initial point is at the same level as a lead-acid battery. There is no chance it is legit.

DannyBee2• 3 years ago

They wouldn't know since they stole it from the DOE website here: https://www.energy.gov/eere/vehicles/articles/fotw-1234-apri....

(The cited paper does not contain this graph, see https://www.osti.gov/pages/servlets/purl/1842609)

Dead_Lemon• 3 years ago

I really enjoy watching Cayrex building interesting batteries on YouTube, like the Reusable Aluminum Air Battery, https://youtu.be/XxJ2FeUi6oI

apienx• 3 years ago

I personally made similar devices in the lab over a decade ago (and yes, with Nafion and benzoquinones). They're very unstable.

I'd file this under gimmick rather than novel tech.

A novel solid, rechargeable air battery

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