How to make an Aluminum-hydrogen peroxide battery.

This is a video on how to make an aluminum hydrogen peroxide battery.
It differs from my previous designs because it uses Fenton's reagent as an oxidizer instead of air. The energy contained in this battery is identical to the energy stored in an aluminum air battery of the same size, but the energy can be delivered much faster. Thus, it can be used to power a wider range of electronic devices.

Fenton's reagent is just a mixture of hydrogen peroxide, water, and an iron salt. It's used to dispose of hazardous laboratory waste and needless to say that it also destroys human flesh, so be careful while handling it.

So what goes on in Fenton's reagent? Iron ions from an iron salt catalyse the dissociation of hydrogen peroxide into OH· and OOH· radicals:
Fe2+ + H2O2 → Fe3+ + OH· + OH−
Fe3+ + H2O2 → Fe2+ + OOH· + H+

The OH· radicals pick up extra electrons at the carbon cathode. The resulting OH- ions migrate towards the anode and react with the aluminium:
Al + 3OH- → Al(OH)3 + 3e-

The radical chemistry that takes place in this battery is not cut and dry, but hydrogen peroxide definitely improves performance, whether it be through radical intermediates, dissociation or decomposition into water and oxygen gas.

The resulting electrons travel out of the anode, through the load and into the cathode, and the cycle repeats.


My camera ran out of batteries while I was shooting the video, so I didn't have the chance to show the short circuit current and open circuit voltage of this particular battery.

Short circuit current: 55mA (that's not a typo)
Open circuit voltage: 1.4V

The power output from this battery is about 7 times higher than that of a regular aluminium air battery of the same size, a definite improvement over the previous design. Unfortunately, there are drawbacks associated with higher power. Since energy is delivered at a higher rate, it is not suited for applications that require a steady current supply over many days.

Nonetheless, making this battery was fun and I hope to find applications for it soon. Thanks for reading :)

Category:

Science & Technology

Tags:

• how
• to
• make
• an
• aluminum
• air
• battery
• fenton's
• reagent
• chemistry
• reduction
• oxidation
• redox
• hydrogen
• peroxide
• iron(II)
• Iron(III)
• H2O2
• Al
• carbon

[uniqueflavour92]

hi, i m a student, well my noob lab does not have iron 3 acetate, can i substitute wirh iron 3 chloride? Can can you provide the half equation of both elctrode? I feel quite blur about the reaction took place. Thanks. Nice video.

[yellowmetalcyborg]

@uniqueflavour92 I've played around with this design and the iron salt is not necessary. In fact, this battery worked better and longer when only an electrolyte and hydrogen peroxide was used. If you really want to use iron salts, iron chloride will also work.

half reactions.

anode:

Al +3OH- ----> Al(OH)3 + 3e

cathode:

H2O2(aq) + 2 H+ + 2 e ----> 2 H2O

The cathode reaction proceeds better in an acidic environment and the anode reaction proceeds better at high pH.

[yellowmetalcyborg]

@uniqueflavour92 I'm sorry about the information blur, I tried to simplify the mechanism, I probably went too far. If you want to know everything about this battery, just ask and I will send a PM.

Cheers

[Eskymak1391]

You cannot buy only carbon rods in USA? You must burn down pencils?

[yellowmetalcyborg]

@Eskymak1391 I definitely can. But my goal is not to make a battery from pre-made parts. Having to make things from everyday objects makes you very resourceful.

[143Alizon]

@yellowmetalcyborg I'm just confirming it from you, it's my first time to make this battery and I am not into a science major to know all of these things. That will be my last question so please don't lose your patience on me :) Thanks a lot.

[yellowmetalcyborg]

@143Alizon I don't like to be harsh. You'll have to excuse me, it was supposed to be a warning. What I say about this battery concerning V and current also applies to other batteries. Here is a video I should have directed you towards before getting angry:

/watch?v=Id3tL2iI0Vw

The Raging Nurd hits several key aspects of batteries and explains them very well. Batteries are obviously much more complicated, but his video should be good for beginners. Tell me if you found it helpful.

Apologies :)

[yellowmetalcyborg]

@143Alizon I have told you before, and I'm starting to lose my patience. Adding more reagents will increase the amount of ENERGY stored. Voltage is determined by what reactions take place in the cell. Voltage is specific to what KIND of battery you made, not to the SA of your electrodes. Battery voltage will increase if you add more cells. You can use copper for your cathodes, but be careful. If any vinegar still remains in your FeIII, you will make Cu(II), which decomposes H2O2 into H2O & O2.

[143Alizon]

@yellowmetalcyborg We've got 2.4 V out of this battery when we made it, but it is not enough to make the dynamo work. Can we raise the voltage of this battery by putting more solutions? and we are thinking if we can use bundle of copper wires instead of the graphite rods, what do you think?

[yellowmetalcyborg]

@143Alizon You will know if something isn't galvanised if it will rust in contact with salt water and air for about a day. If it doesn't look like it rusted, did it tarnish? If it tarnished, it's ungalvanized. You know when something is galvanised when it doesn't rust on contact with salt water for a day. If it bubbles a lot in contact with vinegar, it's probably galvanised. After the zinc layer is removed, you should transfer your ungalvanized iron into another jar with vinegar.