NurdRage - 2011-01-08
We show how to make an Aluminum Air Battery "Air" batteries are batteries that use oxygen from the air as an oxidant for their chemistry. Most batteries on the other hand carry another chemical as their oxidant. Air batteries are currently being researched by scientists as a means of energy storage for everything from cars to laptops. The aluminum air battery is one of the simplest to make. To do just mix 60 grams of salt with 300mL of water. Then attach wires to a ball of aluminum foil and a piece of steel wool. Put the aluminum in the bottom of the salt water and place a paper towel over it. Then place the steel wool on top. You now have an aluminum air battery. The iron in the steel catalyzes the reaction of oxygen with water to make hydroxide and the aluminum reacts with the hydroxide to make aluminum oxide. The power isn't very good because aluminum metal tends to passivate under these conditions. Better chemicals and electrode materials usually fix these issues, but that's beyond the ability of the home lab.
Absolutely love your work. Watched all of your video's! Always excited to see new material!
@NurdRage I just wanted to say that your videos have been fueling my love for chemistry for quite some time, while also keeping me informed and educated of interesting things like this, thanks a ton!
wouldnt the aluminum form a coordination complex in the chemical reaction? and would that affect the reaction at all? Also, thanks for this very good video.
I'm actually amazed that you can get some current and voltage like that - damn, there's so much that can be done with regular household appliances - thank you for the informative videos :)
How long does a battery like this last before the reaction stops producing electricity? Nice video as always!
I've seen aluminum-air cells made using activated carbon as the "air" electrode and they produce a good amount of current.
Nice demo. You might have pointed out that metal oceangoing craft suffer from corrosion (oxidation) resulting from these same electrochemical effects by reason of their metals coming in contact with salt water.
@NurdRage Can You make a video demonstrating the differences between electrolytic and voltaic cells? Its an important topic on the DAT and MCAT. I always get confused on which is anode and cathode. I just know the rule is Reduction is always the cathode, even if its negative. Oh and if you decide to do it, do it before the 24th, as my test is on the 25th :) Also, this is a covered topic so your video would be different (from others) with a real setup as shown in this video vs. just a diagram.
pretty amazing! Please more vids with house hold chemicals!
Thats kind of neat. Your videos are always very interesting and I always look forward to them :P. OHH, just thought of something. I remember in high school (or middle school), we burned a pile of green powder which caused a really cool firework effect, but it built up a lot of ash at the source and eventually was shooting up through a mound of ash. It looked like a volcano almost. I can't quite recall what it was we used.... Hmmm I was going to recommend it, o well. I'll think on it lol.
You make excellent videos. Thanx and keep up the good work!!!
I made three of these cells, wired them in series, and was able to power a small sony fm radio walkman that takes one AA battery. In place of the steel wool, I used aquarium filter charcoal, as it has a better surface area for oxygen to get in, so the cells provide more current.
Since normal foil alredy haves aluminium oxide, i dont think the reaction works as described. Most likely it's forming aluminium hydroxide. Hydroxide is quite a stronger oxidizer than simple oxygen. Instead of: 2Al + 6OH2 --> 3H20 + Al2O3 would be: Al2O3 + 6OH --> 2Al(OH)3
Thanks for doing this. There's a lot of power in aluminium - spread the word. Jack
what can it power and for how long? (hope this wasn't asked already) like a small light or a small fan maybe? Volts: 0.23 Current: >20milliamps If you made a bigger one, would you get more power, like a 5 gallon bucket, a few containers of salt, some rolls of foil and a few bags of steel wool?
I love these vids, I am just a kid that understands absolutely NOTHING about science. I just mix things randomly. I am learning though. Happy experimenting!
You could use sodium carbonate (washing soda) to get much more voltage and current but the battery would only last a day or so since aluminum slowly dissolves in sodium carbonate. Sodium hydroxide will also work but with that you have to be very careful not to use too much of it or you get a violent (and dangerous) reaction.
Well done, but the best and cheapest solution is graphite with alufoil as the electrodes and water and K2CO3 as the electrolyte. This gives about 1.3 to 1.5 Volts and lasts long and graphite can be selfmade (lookup the overunity forum) or from pencils. And Alufoil you can get from every supermarket. Many thanks for your nice videos ! Regards, Stefan.
hey nice, something i can actually do with stuff i already have in my house you probably already know but you can also use fruit and or starches (potato) you could have multiple containers with the same thing and then hook them up in series to add the voltage and maybe run some little electronic device
I suspect that your current is being limited by the availability of oxygen to the iron. I would put in in a flat dish and spread it out. Also a touch of base in the aluminum portion will help take off the oxide better than the chloride alone. Otherwise good design.
@Kendrana I think it would still work, chromium also catalyzes the reaction, just not as well as iron. Go for it :)
Awesome I love these videos
So what if I use copper, aluminum, and salt water (plus maybe some vinegar)? What would my voltage and current be from that? BTW I have a fair bit of all three of these things and PVC pipe and gallon sized barrels so I can make fairly large ones.
hey , can this battery be recharge back or reverse the chemical reaction to turn oxidise aluminium back to just aluminium? Thanks
yay i've just made my own battery. keep up the good work! <3 NurdRage
Awesome as usual!!!
Can other household, or generally easily accessible materiels be used to replace the cathode, anode, and/or the middle substance?
Awesome videos but just curiously how do u know how to make all of these stuff or are they related to ur job?
Awesome. I need to make this. Like right now. I would if I had steel wool.
Good stuff man as always
What happens when you use Ozone instead of just plain air?
But doesn't aluminium foil have an oxide that makes it less conductive?
@Hellsslave666 wikipedia's anode page actually explains it well. Anode/Cathode labeling depends on whether the device in question is producing or consuming power.
@Nurdrage Alright. I'll try it later or tomorrow. The steel wool I have is kinda odd, it doesn't burn like usual iron/steel wool does (like, it gets ember red if you burn it, and all it does is make some smoke with 9V batteries), and even trying to get rid off the Cr with NaOH doesn't really seem to work. Ah well, I'll see how it goes and let you know!
The chemical equations I found in wiki aren't same as what you shown in the video, which one is more reliable?
I am almost positive that if instead of salt you used alum you would have a much more powerful battery.
try doing this with potassium hydroxide (not sodium hydroxide) instead of salt water.
Great video :)
@lexichronicle2 as i've said before in these comments countless times. The rules apply differently to galvanic cells. What you're describing is an electrolytic cell.
@Cooldude32281 The terms were used correctly. It may seem confusing, but think of it this way: when you're dealing with the electrochemical SOURCES of the battery's energy, as opposed to that which it powers, the terms are reversed.
@edv177 Probably there's enough moisture lingering in the glue to maintain some ion mobility. But water isn't an absolute requirement for an electrochemical reaction to occur. For the very coolest perpetual battery ever made, google the Oxford Electric Bell. Might help if you also read Wikipedia's 'History of the Battery'.
so if you were directly bubble oxygen into the solution would it increase the productivity?
The theoretical energy density of an Al O2 battery is the highest of any known technology.
For how long can this give a current?
this doesn't have to do with cemicals but can you show us how to make a cumputer controlled wind chamber/tube please?with smoke/fog to see the air patterns if you put an object inside of the tube that obscures the air path
@Cheejyg air batteries get some of their reactants from the air, as opposed to regular batteries that are completely self contained. An air battery wouldn't work in outer space for example.
@MKplayer7 That's redox. Getting along with the fact that the oxidant gets reduced and the reducer gets oxidized is harder than the actual equations however. :P
Hey, I can now make my Alumina Capacitor now! I've never been entirely sure how to get my hands on Alumina. Before I go spending big bucks on steel wool and aluminium foil. (Or burning my way though the house supply). Alumina forms a protective coating is that right? So I'll probably never get a glass of alumina?
I was waiting so long for you to start making videos again!
Afrotechmods - 2011-01-08
You can do a LOT with 17 milliamps! Can't wait for the next video!