2 hours ago by Ice_cream_suit

Controlling Surface Phase Transition and Chemical Reactivity of O3-Layered Metal Oxide Cathodes for High-Performance Na-Ion Batteries

Junhua Song, Kuan Wang, Jianming Zheng, Mark H. Engelhard, Biwei Xiao, Enyuan Hu, Zihua Zhu, Chongmin Wang, Manling Sui, Yuehe Lin, David Reed, Vincent L. Sprenkle, Pengfei Yan, and Xiaolin Li

ACS Energy Lett. 2020, 5, XXX, 1718–1725 Publication Date:April 28, 2020

https://doi.org/10.1021/acsenergylett.0c00700

"Abstract:

O3-layered metal oxides are promising cathode materials for high-energy Na-ion batteries (SIBs); however, they suffer from fast capacity fade.

Here, we develop a high-performance O3-NaNi0.68Mn0.22Co0.10O2 cathode for SIBs toward practical applications by suppressing the formation of a rock salt layer at the cathode surface with an advanced electrolyte.

The cathode can deliver a high specific capacity of ∼196 mAh g–1 and demonstrates >80% capacity retention over 1000 cycles. NaNi0.68Mn0.22Co0.10O2–hard carbon full-cells with practical loading (>2.5 mAh cm–2) and lean electrolyte (∼40 μL) demonstrate ∼82% capacity retention after 450 cycles.

A 60 mAh single-layer pouch cell has also been fabricated and demonstrated stable performance. This work represents a significant leap in SIB development and brings new insights to the development of advanced layered metal oxide cathodes for alkaline-ion batteries."

3 hours ago by wccrawford

It keeps saying "some lithium-ion batteries".

>a comparable energy capacity and cycling ability to some lithium-ion batteries

Is that just covering their asses, or does this only perform as well as the worst-performing lithium-ion batteries?

an hour ago by Reason077

Performing on par with the "worst" lithium-ion batteries would still be a great success if sodium-ion is cheaper to manufacture. They would still perform much better than lead-acid, Ni-MH, etc. There's a huge demand for cheaper batteries.

an hour ago by skohan

Especially in cases where size/weight is not critically important. This could be a huge deal for something like a home solar setup where batteries can make up a significant portion of the cost.

17 minutes ago by slfnflctd

I've been waiting for competition in this space to heat up for about full decade now. Around the start of the 2010s I was doing a ton of research, and it seemed like a big win was just around the corner... somehow it seems farther away now.

I really hope something - anything - makes it out of the lab at a market-busting price point soon, it might actually give me a chance to restart some projects that have been collecting dust on the shelf for way too long.

an hour ago by hmwhy

To be fair, that doesn't appear to be a quote and the last few words of the sentence you quoted is important:

> ... offering a comparable energy capacity and cycling ability to some lithium-ion batteries already on the market.

Having said that, it seems they do claim in the paper that the performance of their "battery" (really, they only tested a single cathode composition) is "competitive to the commercial LiFePO4-graphite" base on extrapolation of their lab results "to practical large format cells".

I feel funny about that sort of extrapolation in an engineering context, but I'm not an electrochemist and also not a chemical engineer, and I have only skimmed through the abstract, introductions, and conclusions of the paper; so take this comment with a grain of salt.

Edit: typo. Also, I'm not out to trash the work in case my comment comes across as being harsh—marketing aside (which is, sadly, pretty common in high-impact journals), it does seem like a step forward.

2 hours ago by JoeAltmaier

Gotta be dead-heavy? Sodium is atomic weight 22, while Lithum is 7. Three times as heavy? Or is the electrolyte too small a fraction to matter much.

an hour ago by ysleepy

There is very little actual lithium in li-ion batteries. This will not be a problem.

13 minutes ago by mehrdadn

For those wondering: 0.6 grams of lithium out of 45 grams for an 18650 battery, or about 1.3% by weight.

8 minutes ago by JoeAltmaier

Thanks! I just looked that up and was going to post. Beat me to it!

So it is very different - a li-ion battery anode is a tiny part of the battery. A lead-acid battery, its a much larger component.

an hour ago by JoeAltmaier

Hm. There's a lot of lead, in a lead-acid battery. Must be very different.

6 minutes ago by OnlyOneCannolo

Even if it wasn't ... If the energy density and mass density of a sodium battery are between lead-acid and lithium-ion, then an equally capable battery would weigh somewhere in-between.

an hour ago by jasoneckert

It's nice to see this progress - it's definitely been a focus for people for a long time.

I remember one of my chemistry profs in the 1990s telling us how Sodium ion batteries could eclipse Lithium ion batteries once we figure out the practicality to make it work.

an hour ago by baybal2

TIP: The shortage of lithium is nowhere near as "catastrophic" as stockmarket people believe.

The shortage of cobalt is a by far bigger problem. It's basically 80% about Congo, and what happens there.

50% to 80% of global supply can evaporate overnight if something is happening there.

38 minutes ago by Sevaris

Wouldn't a sodium-ion battery be much more environmentally friendly to produce? It seems like there's value in sustainability that makes this attractive over lithium-based batteries.

19 minutes ago by mehrdadn

Sort of off-topic, but why is sodium more abundant than lithium?

4 minutes ago by smolder

The stellar processes that result in stable lithium are rare, like supernovas.[1] Another factor in its rarity as a material is that while it's present in a lot of things, it's not present in quantities for economical recovery.

1. https://www.forbes.com/sites/startswithabang/2019/11/14/this...

5 minutes ago by Tade0

Not a chemist, but apparently even in its stable isotopes the nucleus is barely holding together.

3 hours ago by markdown

Someone tell me how this amazing discovery won't work in practice.

3 hours ago by rzzzt

...in mice!

Sorry, wrong thread.

2 hours ago by dsign

It just never does. Just as in the parallel universe with personal airplanes powered by sodium batteries, Lithium-ion and four-wheeled cars never made it to the mainstream. Incumbent power.

3 hours ago by ShorsHammer

There's a universe of uses for batteries. Really depends on what you want it for.

For the average person using consumer products they are usually concerned with energy density and cost. Apart from electric cars most companies don't really care about no. of cycles, especially for phones.

2 hours ago by dgoldstein0

... but don't we charge our phones every day? 1000 cycles feels like a minimum for that - would be required for a phone to last 3 years.

an hour ago by viktorko

In my experience phone batteries start to deteriorate after about two year.

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