31–40 of 88 posts
So I've posted this before, but aluminum smelting is just plain old too hard for this to be as cheap as batteries. I mean, it's great if you're Alcoa, an aluminium smelter, but let's take a look at bulk prices: Aluminium costs $1.80/kg: http://www.indexmundi.com/commodities/?commodity=aluminum Alumina, the product of the aluminium-air reaction, costs ~$0.45/kg: http://www.indexmundi.com/en/commodities/minerals/bauxit…
"Because the car would still rely on its regular rechargable lithium-ion battery most of the time and would switch to the aluminum-air battery as a backup only if the lithium-ion battery ran out, and because most car trips are 50 kilometres or less, Alcoa estimates the aluminum-air batteries would only need to be changed about once a year." This is a chemical battery with very limited lifespan. Additionally without a…
It's highly recyclable. Aluminium oxide (the result of the reaction in the battery) is one of the feedstocks for industrial aluminium smelting. Recyclable isn't necessarily the same as 'efficient' or 'a good idea' though. It's energy intensive (haven't checked the efficiency of 'recharging'), and additionally has, as a byproduct, massive amounts of CO2 even before considering CO2 emitted in generating the electricity…
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It's highly recyclable. Aluminium oxide (the result of the reaction in the battery) is one of the feedstocks for industrial aluminium smelting. Recyclable isn't necessarily the same as 'efficient' or 'a good idea' though. It's energy intensive (haven't checked the efficiency of 'recharging'), and additionally has, as a byproduct, massive amounts of CO2 even before considering CO2 emitted in generating the electricity…
It's energy intensive (haven't checked the efficiency of 'recharging'), and additionally has, as a byproduct, massive amounts of CO2 even before considering CO2 emitted in generating the electricity required for the smelting process. Aw come on! I'd rather see thinking two or more steps ahead from the HN crowd. If the CO2 emitted from the battery's materials came from the atmosphere in the first place, this will be a…
The carbon emissions of aluminum smelting come from the carbon electrodes in the electrolytic cell-- you're essentially burning them to pull the oxygen atoms off the aluminum oxide molecule.
http://en.wikipedia.org/wiki/Aluminium_smelting
Carbon electrodes used in industrial processes are generally formed from processed coal and mineral graphite: the fossiliest of the fossil fuels. You could theoretically produce synthetic bulk carbon from atmospheric CO2 using the Bosch process, (http://en.wikipedia.org/wiki/Bosch_reaction) at incredible cost per kilogram of carbon produced, which would then directly increase the cost per kilogram of aluminum smelted.
metal-air batteries (fuel cells), rechargeable and not, is the future. Having comparable to gasoline energy density, yet higher efficiency - 60-90% vs. 30% of gasoline, it will transform cars and especially planes (subsonic ones). You can imagine that it is absolutely not an issue to replace a 100Kg spent aluminum fuel cell block on a small plane at airport. It would also be better than gas turbine for bigger commerc…
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It's energy intensive (haven't checked the efficiency of 'recharging'), and additionally has, as a byproduct, massive amounts of CO2 even before considering CO2 emitted in generating the electricity required for the smelting process. Aw come on! I'd rather see thinking two or more steps ahead from the HN crowd. If the CO2 emitted from the battery's materials came from the atmosphere in the first place, this will be a…
>If the CO2 emitted from the battery's materials came from the atmosphere in the first place, this will be a closed cycle and won't increase global CO2 levels. The carbon emissions of aluminum smelting come from the carbon electrodes in the electrolytic cell-- you're essentially burning them to pull the oxygen atoms off the aluminum oxide molecule. http://en.wikipedia.org/wiki/Aluminium_smelting Carbon electrodes use…
Again, there's no fundamental reason why this must be the case.
You could theoretically produce synthetic bulk carbon from atmospheric CO2 using the Bosch process, (http://en.wikipedia.org/wiki/Bosch_reaction) at incredible cost per kilogram of carbon produced, which would then directly increase the cost per kilogram of aluminum smelted.
Yes, but this is like saying that because our present economic/industrial configuration is the way it is, there's no escape from emitting carbon, which is simply circular logic. Or, maybe you do understand the implication, which is that the only way out is for us to make energy much cheaper across the board.
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Maybe if the aluminum could be packaged as a liquid or a gel, it could be pumped in and out like gas.
Something that requires 1,221 F (660.3 C) doesn't seem like something you would want to sit on or pump without serious protection.
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It's not reversible in the car, but it is reversible in an aluminum smelter. The power cell is turning the metal into aluminum oxide, which is (mostly) how we find Al in its ore form. So once you burn it out, it gets shipped back to Alcoa and they treat it like some nice clean ore and shortly turn it back into metallic Al. Which is not entirely energy-cheap, but at current prices of less than $1/lb isn't too bad. You…
with that definition of recycling even gasoline is recyclable in plants :)
Is there anybody advocating for this besides aluminum smelters?
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Just use aluminum powder or prills. Bonus you get a huge surface area so the reactions happen fast.
and just dump the alumina result out the tailpipe - its just ceramic dust. And refill with new powder. So it becomes very much like the process of gasoline fueling.