Aluminium-air batteries
Specific energy: 1300 Wh/kg
Specific power: 200 W/kg
Considerations
Rechargeability
Not suited for electric vehicles
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
Energy return on inputs - quick estimate This alone shows how (calculation loading)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
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
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]