Aluminium-air batteries

From the change wiki
Non-rechargeable
Specific energy: 1300 Wh/kg
Specific power: 200 W/kg

Considerations

Rechargeability

None

Not suited for electric vehicles(...)( because, although it could have a very high range like 1000km or more, you wouldn't be able to charge it; it could only be swapped out; swapping out early (to running out of energy and getting stranded) would be extremely wasteful )nor grid energy storage, because the batteries are not rechargeable.

Maybe suited for electric planes, because...

  • batteries can be made in specific sizes suited for flight lengths
  • the high energy density may well be worth the disposability
  • battery voltage and output power remain stable throughout usage (important because full power is always needed for emergency landings).

EROI

Very low
al_air_battery.energy_by_mass
1300 watt hours per kilogram
Typical "specific energy" of an aluminum-air battery
aluminium_production.energy_by_mass
17000 kWh/tonne
Energy required to produce aluminium metal
"Aluminium production is energy intensive. About 17,000 kWh of electricity are required to produce 1 tonne of aluminium." [www.sciencedirect.com/topics/engineering/aluminum-production Aluminum Production - an overview - ScienceDirect Topics]

Energy return on inputs - quick estimate al_air_battery.energy_by_mass / aluminium_production.energy_by_mass%(calculation loading) This alone shows how inefficient it would be to manufacture a new battery every time we want to store some energy. It would actually be even more inefficient in real life: The above calculation didn't factor in the energy to construct the battery, just the material (aluminum). Such a low EROI might still be ok in the case of electric planes, as planes are only a very small fraction of the world's transport-related energy use. TODO: add pie chart

Energy density

Very high

Typical: 1300 watt hours per kilogram
Attempted: 2000 watt hours per kilogram

These are far higher than lithium-ion batteries which are only about 200 watt hours per kilogram.

Materials

Abundant

Unlike some other battery types, aluminium-air batteries use mostly just aluminium, which is one of the most abundant metals on Earth.

Misc technical challenges

  • High anode cost [ELABORATION needed]
  • Byproduct removal (when using traditional electrolytes) [ELABORATION needed]

External links

See also