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A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

science.org

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Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#51

Post by jillesvangurp »

AtlasBarfed wrote: post #42
jillesvangurp wrote: post #40

Earlier quoted context omitted.

Is that fresh out of the factory or after a few years of service? I think a lot of the metrics around hybrids are a bit optimistic. In the same way that official metrics for EV ranges are usually a bit more than is realistic. Hybrids running on battery are about as efficient as an EV. When you enter the highway, they turn into ordinary ICE engines. If you use your prius exclusively for traffic in your neighborhood, y…

Ice hybrids can run on the Atkinson cycle, which fas been explained to me as diesel range from gasoline. I believe this is because the electric motor can handle the torque variation so the engine runs in a more consistent optimized torque band

The most optimal thing is to just use ICE engines as a generator/range extender that tops up the battery. Most hydrogen vehicles actually work like that as well: the fuel cell is basically used as a generator to top up the battery.

Some of the Chinese plugin hybrids are starting to do this. Those basically are EVs with a generator bolted on to extend the range to something crazy like well over 1000 miles. These vehicles are far simpler to build and mechanically a lot simpler. And the generator is of course an optional extra if your battery is big enough. More like a safety blanket for the range anxious.

Edison trucks (a Canadian startup) is doing putting generators on their trucks. They've built and designed their own electrical logging truck designed for the extremes of that business. Pretty awesome vehicle. Effortless pulls huge loads over unpaved roads. Basically, it has no gears so it is super simple to operate and it drives like a car. A pretty sporty one even. The generator is just there for when they go out into the middle of nowhere where they can't charge the truck. It's purely a range extender.

If you think about it, you could just buy an off the shelf generator, shove it on a trailer and hook it up to your EV. If you have a EV pickup, you can just sacrifice some space in the back. This isn't that hard. You only need a few kw of output from the generator. A simple, small, and cheap one would be good enough.

The reason companies like Toyota are trying to sell you a much harder to maintain and much more complicated solution instead is not because they haven't thought about it but because they have a large sunken investment in ICE engine manufacturing that they want to milk for a bit longer.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#52

Post by audunw »

giantg2 wrote: post #26

I'm a bit excited but also a bit tired of hearing about all these batteries. I just want someone to wake me up when we have a commercially available 1kwh+/kg with decent durability, decent price, and good safety. Maybe this is a good idea for an ammoseek website but for batteries that can send alerts. I'm honestly surprised a quick search didn't turn one up.

That feels like a very high bar. A really good 500Wh/kg battery would already be completely revolutionary. That’s when you start to unlock practical short range electric flights for instance. It’d probably be enough for all forms of land transportation as well (except very small niches, like if you need to cross a huge desert off-road)

If you get to 1kwh/kg I don’t think you even need good durability and low price to have a revolutionary battery. At that energy density it could make economic sense to do medium range battery electric planes, even if you need to replace the battery every year. The operational costs related to using jet fuel (both fuel costs and engine maintenance) are huge. So the airplane industry can work with batteries that are more expensive and that requires more maintenance than what the EV market would accept.

I’m sure there’s a bunch of other niches for such a battery.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#53

Post by lmz »

jillesvangurp wrote: post #51
AtlasBarfed wrote: post #42

Earlier quoted context omitted.

Ice hybrids can run on the Atkinson cycle, which fas been explained to me as diesel range from gasoline. I believe this is because the electric motor can handle the torque variation so the engine runs in a more consistent optimized torque band

The most optimal thing is to just use ICE engines as a generator/range extender that tops up the battery. Most hydrogen vehicles actually work like that as well: the fuel cell is basically used as a generator to top up the battery. Some of the Chinese plugin hybrids are starting to do this. Those basically are EVs with a generator bolted on to extend the range to something crazy like well over 1000 miles. These vehic…

But running such a series hybrid with minimal charge of the batteries means almost all power is from the engine. And if that is undersized that won't end well.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#54

Post by lupusreal »

thomasmg wrote: post #38
BWStearns wrote: post #33

Earlier quoted context omitted.

Interesting. So if it was used for aviation then your takeoff weight would be lower than your landing weight. That'll be counterintuitive.

Unless if the spent battery calls are released during the flight, via parachute, to be recharched later. We currently call spent batteries "empty" but in this case spent = "full" (of oxygen).

Totally impractical for virtually any application.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#55

Post by BWStearns »

thomasmg wrote: post #38
BWStearns wrote: post #33

Earlier quoted context omitted.

Interesting. So if it was used for aviation then your takeoff weight would be lower than your landing weight. That'll be counterintuitive.

Unless if the spent battery calls are released during the flight, via parachute, to be recharched later. We currently call spent batteries "empty" but in this case spent = "full" (of oxygen).

I imagine the extra complexity, parachute and release system weight, and risk would nix that.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#57

Post by bryanlarsen »

audunw wrote: post #50
beAbU wrote: post #17

Earlier quoted context omitted.

To add on to that, battery "lifetime" is typically defined as 80% of original capacity. So after 1000 full cycles, you still have 80% capacity left!

It should be said that at that point you don’t have very many charge cycles left after the capacity drops below 80%, and the capacity will drop a lot faster for every charge cycle after that point. I don’t have exact numbers.. based on graphs I’ve seen I would guess that if the original cycle life was 1000 cycles you may have another 500 cycles until the battery is actually unusable. But it probably depends a lot on…

If 1000 cycles is 250,000 miles, then an additional 500 cycles also seems like a large number.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#58

Post by 0cf8612b2e1e »

jillesvangurp wrote: post #51
AtlasBarfed wrote: post #42

Earlier quoted context omitted.

Ice hybrids can run on the Atkinson cycle, which fas been explained to me as diesel range from gasoline. I believe this is because the electric motor can handle the torque variation so the engine runs in a more consistent optimized torque band

The most optimal thing is to just use ICE engines as a generator/range extender that tops up the battery. Most hydrogen vehicles actually work like that as well: the fuel cell is basically used as a generator to top up the battery. Some of the Chinese plugin hybrids are starting to do this. Those basically are EVs with a generator bolted on to extend the range to something crazy like well over 1000 miles. These vehic…

I previously wondered about the generator trailer. Hook it up for long trips and travel without fear.

Can a typical EV battery charge while driving or would they need to be redesigned for this purpose?

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#59

Post by Tagbert »

jillesvangurp wrote: post #51
AtlasBarfed wrote: post #42

Earlier quoted context omitted.

Ice hybrids can run on the Atkinson cycle, which fas been explained to me as diesel range from gasoline. I believe this is because the electric motor can handle the torque variation so the engine runs in a more consistent optimized torque band

The most optimal thing is to just use ICE engines as a generator/range extender that tops up the battery. Most hydrogen vehicles actually work like that as well: the fuel cell is basically used as a generator to top up the battery. Some of the Chinese plugin hybrids are starting to do this. Those basically are EVs with a generator bolted on to extend the range to something crazy like well over 1000 miles. These vehic…

What you are describing are series hybrids where the power source generate electricity and the wheels are driven from the electric motor.

Nissan sells this as their E-Power system Hybrid. The Chevy Volt plug-in hybrids were primarily series hybrids when in hybrid mode.

Running the gas engine to charge the battery and drive the wheels is not as efficient as just using a large EV battery but the trade offs in cost, weight, and range may make it worthwhile for now.

Re: A room temperature Li2O-based lithium-air battery enabled by a solid electrolyte

#60

Post by gnarcoregrizz »

I thought the problem with all of these metal air batteries is the sluggish oxygen reduction reaction at the air cathode. It just seems too slow for a high power density - need high surface area. The air cathode in this experiment is a gas diffusion layer embedded with trimolybdenum phosphide nanoparticle (seems common with these, others use platinum and iridium), with a current density of 0.1 mA/cm2. Need 1m2 of air cathode for 10 amps. I wonder how that ORR can be sped up or use smaller surface area. Could some kind of forced induction supercharger type thing work for these? I'm not a chemist.
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