Lithium Oxygen batteries

[Fecn]

If this ever comes to anything, then our bikes are going to get a lot lighter

'Air fuelled' battery tech invented in Scotland • The Register

 

[Mussels]

Interesting but it reads like an MIT press release, it must be finding sponsorship time in Scotland.

 

[flecc]

Thanks for the information Fecn. As you say, if it ever comes to anything it would be good.

In recent decades there seem to be an ever increasing rate of battery "breakthrough" announcements, but very little ever seems to come to fruition.

The few things that do fall well short of the original predictions and are often radically different. For example I remember that li-polymer was to be a low energy density ultra rapid charge system for e-cars, but has ended up as a high density slow charge system for anything but cars!
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[rog_london]

Thanks for the information Fecn. As you say, if it ever comes to anything it would be good.

In recent decades there seem to be an ever increasing rate of battery "breakthrough" announcements, but very little ever seems to come to fruition.

The few things that do fall well short of the original predictions and are often radically different. For example I remember that li-polymer was to be a low energy density ultra rapid charge system for e-cars, but has ended up as a high density slow charge system for anything but cars!
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Batteries using oxygen have been around for a while - they were used in deaf-aids at one time, though I don't know if they still are. However, they are non-rechargeable low-current jobs, and I suspect there may be an insurmountable problem when it comes to designing batteries for very high current purposes - the volume of oxygen the battery will need.

Obviously if oxygen is being gently absorbed by means of air flowing through the battery that's going to relate directly to the current available. You'd need a gale blowing through to generate serious current if the oxygen is to be a part of a chemical reaction, and I suspect also the surface absorbing oxygen would either have to be physically large or to have a very high surface area in a small space by reason of being porous.

This is all guesswork on my part, of course. If you're talking about powering phones, or perhaps small computers, then I'd say it's possible, but a traction battery would be a different proposition.

Rog.

 

[flecc]

Batteries using oxygen have been around for a while - they were used in deaf-aids at one time, though I don't know if they still are.

Rog.

Yes, I remember those zinc-air ones well, my father used to use the NHS ones in his hearing aid. I tried a couple in other applications but they were very short lived under load then, possibly oxygen starvation as you said, only three tiny pinholes in the base after the sticky label was removed. They probably still use them.
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[Fecn]

Yes, I remember those zinc-air ones well, my father used to use the NHS ones in his hearing aid. I tried a couple in other applications but they were very short lived under load then, possibly oxygen starvation as you said, only three tiny pinholes in the base after the sticky label was removed. They probably still use them.
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They most certainly do still use them. Zinc-Air are one of the highest power densities around.

Here's a nice gotcha for this technology... (aside from the obvious one about getting enough oxygen through it for any decent kind of current delivery)

Lithium has an atomic weight of 3
Oxygen has an atomic weight of 8
Oxygen is absorbed by the battery during discharge... specifically two lithium atoms bond with one oxygen molecule to make 2Li2O2 (Lithium Oxygen)

Adding the oxygen molecules onto the lithium will make it heavier. This means that if the lithium in your battery weighed 3KG when your battery was fresh, it would have gained a whopping 8KG of weight by the time you'd discharged it.

Just what you need... a really really heavy flat battery to struggle home with

 

[flecc]

Oh well, another good idea bites the dust then!
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