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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

#4

Post by timerol »

fs_tab wrote: post #2

From the abstract: A lithium-air battery based on lithium oxide (Li2O) formation can theoretically deliver an energy density that is comparable to that of gasoline.

This particular Li2O battery is a little under 700 Wh/kg, with the theoretical maximum being 11k Wh/kg, compared to gasoline's 13k Wh/kg. It's an incredible accomplishment that they have managed to get such a reaction reasonably stable. Minor improvements to the battery cited in the paper would be beyond the theoretical limits of existing commercial lithium chemistries.

> The results shown in fig. S9 indicate that this solid-state Li-air battery cell can work up to a capacity of ~10.4 mAh/cm2, resulting in a specific energy of ~685 Wh/kgcell. In addition, the cell has a volumetric energy density of ~614 Wh/Lcell because it operates well in air with no deleterious effects (supplementary materials, section S6.3)

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

#5

Post by norrsson »

timerol wrote: post #4
fs_tab wrote: post #2

From the abstract: A lithium-air battery based on lithium oxide (Li2O) formation can theoretically deliver an energy density that is comparable to that of gasoline.

This particular Li2O battery is a little under 700 Wh/kg, with the theoretical maximum being 11k Wh/kg, compared to gasoline's 13k Wh/kg. It's an incredible accomplishment that they have managed to get such a reaction reasonably stable. Minor improvements to the battery cited in the paper would be beyond the theoretical limits of existing commercial lithium chemistries. > The results shown in fig. S9 indicate that th…

Usual disclaimer regarding the energy density of gasoline: current gasoline engines have an efficiency of 10-30% while EVs are around 90%.

So to reach similar kWh/g we're looking at ~3k Wh/kg

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

#6

Post by lukevp »

norrsson wrote: post #5
timerol wrote: post #4

Earlier quoted context omitted.

This particular Li2O battery is a little under 700 Wh/kg, with the theoretical maximum being 11k Wh/kg, compared to gasoline's 13k Wh/kg. It's an incredible accomplishment that they have managed to get such a reaction reasonably stable. Minor improvements to the battery cited in the paper would be beyond the theoretical limits of existing commercial lithium chemistries. > The results shown in fig. S9 indicate that th…

Usual disclaimer regarding the energy density of gasoline: current gasoline engines have an efficiency of 10-30% while EVs are around 90%. So to reach similar kWh/g we're looking at ~3k Wh/kg

Is there a similar volumetric equivalent measurement or is it all about energy density by weight? Like, if the batteries are lightweight but massive, that would also be a bit of a problem since the structure to safely transport a large volume could be expensive and heavy.

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

#7

Post by Xamayon »

If it can be made small enough for use in mobile devices, I wonder whether the need for air/oxygen might require compromising on water-tightness. Would an oxygen permeable waterproof membrane allow enough through for operation? It would be interesting if instead of just for cooling, future high powered devices might also need a fan to feed the battery!

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

#8

Post by sn0wf1re »

lukevp wrote: post #6
norrsson wrote: post #5

Earlier quoted context omitted.

Usual disclaimer regarding the energy density of gasoline: current gasoline engines have an efficiency of 10-30% while EVs are around 90%. So to reach similar kWh/g we're looking at ~3k Wh/kg

Is there a similar volumetric equivalent measurement or is it all about energy density by weight? Like, if the batteries are lightweight but massive, that would also be a bit of a problem since the structure to safely transport a large volume could be expensive and heavy.

Looks like the created cell is 614 Wh/L from the above comment. Gasoline is ~2.2kWh/L [0]. So my take is that even with the created cell the density is not going to be an issue with car or grid batteries -- only [0] This uses the 3kWh/kg that was provided above and a density of gasoline of .75g/mL

    units
    You have: 0.7429 g/mL * 3 kWh/kg
    You want: kWh/L
 * 2.2287

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

#9

Post by andy_ppp »

norrsson wrote: post #5
timerol wrote: post #4

Earlier quoted context omitted.

This particular Li2O battery is a little under 700 Wh/kg, with the theoretical maximum being 11k Wh/kg, compared to gasoline's 13k Wh/kg. It's an incredible accomplishment that they have managed to get such a reaction reasonably stable. Minor improvements to the battery cited in the paper would be beyond the theoretical limits of existing commercial lithium chemistries. > The results shown in fig. S9 indicate that th…

Usual disclaimer regarding the energy density of gasoline: current gasoline engines have an efficiency of 10-30% while EVs are around 90%. So to reach similar kWh/g we're looking at ~3k Wh/kg

Does the engine and drive train weight make these calculations even better for electric vehicles?
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