seilgu - 10-1-2020 at 03:26
I'm a newbie that has only done ferrofluid and chlorate cells.
I'm recently interested in making a Li-S battery at home. I don't know how to start, anybody else interested?
Seeing the sulfur ring S8 becoming Li2S4, Li2S2, LiS should be fascinating, and by watching how the battery runs in real time we can probably see the
dendrite growth and try adding stuff to suppress it. It could be fun.
So it seems that Li2S turns into HS when in contact with water, one can either increase the pH to reduce that, or eliminate the water in the
atmosphere. I plan to build a glove box with Argon gas protection. Or maybe if we seal the battery under a film of oil or some inert liquid, it could
work?
And I'm not sure what chemicals I should start with. Probably get some LiOH or LiCO3 solution, and use some binder to make a sulfur electrode.
I'm asking here because I'm concerned if there's any potential danger I didn't think of. Besides the toxic HS which should be easy to detect, and fire
hazards that could possibly fume a lot. Is there any other danger?
[Edited on 10-1-2020 by seilgu]
Ubya - 10-1-2020 at 05:12
have you read any papers on the subject?
seilgu - 10-1-2020 at 23:46
@Ubya I read a few but I don't think the papers cover the basics on how to get started with a DIY battery lab.
What I'm looking for is how to get started, or if possible, a way to make the electrolyte myself, which I think consists of lithium polysulfides. I've
read a bit on the synthesis, but not yet enough to determine whether it's safe to do it at home. Basically what I know is that if there's water
present, hydrogen sulfide will be produced, but under basic conditions it's reduced, yet I don't know if the amount presents a hazard.
If I can find a way to make the electrolyte safely, the rest will probably be my own experimentation and would require no further help.
Sulaiman - 11-1-2020 at 01:35
I'm not proficient in electrochemistry, but a quick read makes me think that you are aiming very high : https://en.wikipedia.org/wiki/Lithium%E2%80%93sulfur_battery
and
Attachment: eaay2757.full.pdf (4.7MB)
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Your progress will be limited
(due to your lack of access to an electron microscope, and similarly expensive analytical and diagnostic tools, and knowledge)
by cost, available space, time, effort and luck,
as this looks to me a little like Eddison developing the lightbulb
- try hundreds of approaches until one works.
If recent research in a University laboratory only achieved 200 charge-discharge cycles (.pdf above)
what is your aim ?
(e.g. if just a few charge-discharge cycles is enough, then ok, go for it)
I personally would not start in this direction because I'm neither dogged nor patient enough,
but I will be interested in your progress and I wish you well.
I hope that you will adopt suitable safety precautions.
welcome to SM
clearly_not_atara - 11-1-2020 at 21:09
Liquid-electrolyte/solid-electrode lithium-sulfur batteries are extremely complicated and would not be feasible to construct. Research on these
batteries is intense due to excellent theoretical properties; all of the best attempts use nanostructured electrodes that combine a high area:volume
ratio with some engineered surface reactivity. It's not something you can make with off-the-shelf equipment.
By contrast, the liquid-electrode/solid-electrolyte sodium-sulfur battery is conceptually very simple, although the high operating temperature
certainly poses some difficulty:
http://en.wikipedia.org/wiki/Sodium-sulfur_battery
It's simple: you have some liquid sodium, some liquid sulfur, and a solid in between that conducts Na+ ions. Sodium and sulfur are both liquid by 115
C, but you need to go all the way up to 300 C for a standard Na-S battery. This seems like something you could mess around with on a small-scale --
but it certainly wouldn't be easy!
[Edited on 12-1-2020 by clearly_not_atara]
BaFuxa - 22-1-2020 at 09:07
Maybe you should investigate on the Zebra battery. Lots of patents lying around.
I think it is an exciting type of battery, which could be used as a secondary battery on a hybrid vehicle. It is one of my long term projects, just
because it makes a good excuse to use sulfur and sodium 
ThoughtsIControl - 9-6-2020 at 10:59
https://www.mpoweruk.com/zebra.htm
I wasn't aware of what the Zebra battery was. So, I've been reading about it for a little while now. To break it down, it's essentially a sodium
nickel chloride battery that utilizes a molten electrolyte. It's got a high energy density and can work efficiently with high amounts of molten
NaNiCl.
The downfall is obviously the energy required to heat the NaNiCl which can be costly. I was thinking --> would this type of battery be efficient
for third world countries? Of course, the problem is still the heat required to keep the battery molten. However, what if you just never let it cool
down?
Very interesting concept!
https://www.sciencedirect.com/topics/engineering/sodium-nick...
Here's a good source with excellent figures if you want to scroll through.
"Fuel cell efficiency 48.4%
Battery efficiency 89%
Fuel cell price range £305 – 2287 kWh−1
Battery price range £53 – 233 kWh−1"
[Edited on 9-6-2020 by ThoughtsIControl]