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Stabilization of gamma sulfur at room temperature to use in Li-S batteries

nature.com

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Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#11

Post by Schroedingersat »

mjevans wrote: post #9
jojobas wrote: post #6

So they are claiming 800 mA-h per gram, which at 2.5V Li-S voltage gives about 7.2 megajoules per kilo, 1.5 the energy density of TNT. Somehow I don't want to be anywhere near a battery with that kind of energy density.

A quick search on Google: petrol megajoules Petrol/gasoline 44-46 MJ/kg Diesel fuel 42-46 MJ/kg Crude oil 42-47 MJ/kg You're already near far denser volatile chemicals, even if it isn't you driving someone else is somewhere.

The key difference is the hydrocarbon "battery" has a volumetric energy density of around 12kJ/L if you include both halves where the sulfur one is still around 7MJ/L

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#12

Post by jillesvangurp »

mjevans wrote: post #9
jojobas wrote: post #6

So they are claiming 800 mA-h per gram, which at 2.5V Li-S voltage gives about 7.2 megajoules per kilo, 1.5 the energy density of TNT. Somehow I don't want to be anywhere near a battery with that kind of energy density.

A quick search on Google: petrol megajoules Petrol/gasoline 44-46 MJ/kg Diesel fuel 42-46 MJ/kg Crude oil 42-47 MJ/kg You're already near far denser volatile chemicals, even if it isn't you driving someone else is somewhere.

And it's far more common for ICE cars to actually explode/burn out. And particularly petrol fires can be very dangerous and lethal. Cars can combust while parked, while driving, or when you get in an accident. It's one of the most common causes for fire brigades to have to take some action. Diesel is a bit safer than petrol but it will burn if things get hot enough. And cars and trucks overheat and catch fire for all sorts of reasons.

EVs are much safer both in absolute numbers and relative numbers (if you consider there are far less EVs than ice vehicles). They do occasionally burn of course. And usually those fires aren't very explosive and give you plenty of time to get out of the vehicle and to safety. Fatalities/injuries are rare with this.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#14

Post by jillesvangurp »

AtlasBarfed wrote: post #3

Other sources say 4000 cycles in one year of testing and the battery is still going strong. Apparently they used some chemical vapor deposition to dope sulfur in a carbon mesh, and apparently gamma sulfur was created in the process, which was accidental, they're trying to determine why their process created it. Claim 3x the capacity of current lithium ion. That would be, what 600 wh/kg? 750? That seems unbelievable.

4000 cycles is pretty impressive. Worth pointing out just how good that is: if you fully charge the battery every day of the year, that would mean close to 11 years of very intensive use. 4000 times a typical maximum range of 250 miles would mean driving a million miles. Some taxis get that kind of mileage of course. But most drivers would take quite a bit of time to get there.

In short, if you are lucky enough to own a vehicle with such a battery, it needing replacement is not going to be an event that you should have to worry about for decades if you drive it normally. Which would mean doing about 14K miles per year; or about 71 years.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#15

Post by roflc0ptic »

epgui wrote: post #5
Animats wrote: post #4

It's nice to see a battery chemistry article that admits they're in the early stages of getting some new chemistry to work. The usual battery article is "we got this to happen in a test tube, huge world-changing breakthough Real Soon Now". Those have become tiresome. This article seems to have much less bullshit than most. Hope this one works.

It's an academic paper in Nature, it's not CNBC.

more like university press

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#16

Post by lazide »

jillesvangurp wrote: post #12
mjevans wrote: post #9

Earlier quoted context omitted.

A quick search on Google: petrol megajoules Petrol/gasoline 44-46 MJ/kg Diesel fuel 42-46 MJ/kg Crude oil 42-47 MJ/kg You're already near far denser volatile chemicals, even if it isn't you driving someone else is somewhere.

And it's far more common for ICE cars to actually explode/burn out. And particularly petrol fires can be very dangerous and lethal. Cars can combust while parked, while driving, or when you get in an accident. It's one of the most common causes for fire brigades to have to take some action. Diesel is a bit safer than petrol but it will burn if things get hot enough. And cars and trucks overheat and catch fire for all…

Petrol cars do not explode with any frequency.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#17

Post by thehappypm »

jojobas wrote: post #6

So they are claiming 800 mA-h per gram, which at 2.5V Li-S voltage gives about 7.2 megajoules per kilo, 1.5 the energy density of TNT. Somehow I don't want to be anywhere near a battery with that kind of energy density.

TNT is much more about power than energy. Releasing a megajoule in a tiny fraction of a second is far more destructive than burning a quart of gasoline in a bucket.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#18

Post by Animats »

epgui wrote: post #5
Animats wrote: post #4

It's nice to see a battery chemistry article that admits they're in the early stages of getting some new chemistry to work. The usual battery article is "we got this to happen in a test tube, huge world-changing breakthough Real Soon Now". Those have become tiresome. This article seems to have much less bullshit than most. Hope this one works.

It's an academic paper in Nature, it's not CNBC.

That means much less than it used to.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#19

Post by Klinky »

Schroedingersat wrote: post #11
mjevans wrote: post #9

Earlier quoted context omitted.

A quick search on Google: petrol megajoules Petrol/gasoline 44-46 MJ/kg Diesel fuel 42-46 MJ/kg Crude oil 42-47 MJ/kg You're already near far denser volatile chemicals, even if it isn't you driving someone else is somewhere.

The key difference is the hydrocarbon "battery" has a volumetric energy density of around 12kJ/L if you include both halves where the sulfur one is still around 7MJ/L

How are you calculating the volumetric energy density and the energy content of a liter of gasoline? 12kJ/L seems low.

Re: Stabilization of gamma sulfur at room temperature to use in Li-S batteries

#20

Post by Schroedingersat »

Klinky wrote: post #19
Schroedingersat wrote: post #11

Earlier quoted context omitted.

The key difference is the hydrocarbon "battery" has a volumetric energy density of around 12kJ/L if you include both halves where the sulfur one is still around 7MJ/L

How are you calculating the volumetric energy density and the energy content of a liter of gasoline? 12kJ/L seems low.

In the context of comparing it to TnT or a Sulfur battery you need the oxygen too.
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