Alufoil-MnO2 Battery cell with 2.67 Volts ! WOW !

[cayrex]

https://www.youtube.com/watch?v=8YG0nh_aYBA

My 15 min aluminium battery project from oluchem! Spec: 2.65V and 100 mA! This construction of this cell is like Daniell cell. Two metals in two different types of electrolyte (Cu in CuSO4 and Zn in ZnSO4 connected with a salt bridge).

[hartiberlin]

Very well done Cayrex !
The music is a bit too loud. But Did you say at 2:40 that you have just table salt NaCl under the aluminium ?

So what is the best configuration yet ?

Can you try to light a few yellow and green LEDs with it ?

At around 250 MilliWatts output of such a cell these LEDs should be really bright !

How strong was your H2SO4 acid ? Did you just use car battery acid or stronger ?

Did you try to recharge the cell ? Does this work ? For recharging it is probably the best to have
AlCl3 electrolyte at the aluminiumfoil to put the Aluminium ions back onto the foil...

Did you have a graphite plate ontop of the MnO2 ? Or did you just use the MnO2 powder only ?
Many thanks.

Regards, Stefan.

[profitis]

Boss'Did you try to recharge the cell ? Does this work ? For
recharging it is probably the best to have
AlCl3 electrolyte at the aluminiumfoil to put the
Aluminium ions back onto the foil...'

Unfortunately aluminum anodes in aquaeous chemistry is total irreversible.no aluminum plates out frm Al sols.you want to try zinc anode in NaOH for moderate reversability.you want to try KNO3/H2SO4 or K2Cr2O7/H2SO4 aq. with carbon rod for potent cathode.

[cayrex]

Very well done Cayrex !
The music is a bit too loud. But Did you say at 2:40 that you have just table salt NaCl under the aluminium ?

So what is the best configuration yet ?

Can you try to light a few yellow and green LEDs with it ?

At around 250 MilliWatts output of such a cell these LEDs should be really bright !

How strong was your H2SO4 acid ? Did you just use car battery acid or stronger ?

Did you try to recharge the cell ? Does this work ? For recharging it is probably the best to have
AlCl3 electrolyte at the aluminiumfoil to put the Aluminium ions back onto the foil...

Did you have a graphite plate ontop of the MnO2 ? Or did you just use the MnO2 powder only ?
Many thanks.

Regards, Stefan.

Uf,... so many questions 

Orginal setup: Chatode: MnO2 and graphite in H2SO4, Anode: Al in NaOH and  in the middle Na2SO4 because of the reaction NaOH + H2SO4 = Na2SO4 + H2O

the salt which I use is the side product from my reaction  CoCl2 + NaOH -> Co(OH)2 + NaCl. Co(OH)2 was at the bottom and NaCl on the top,.... I use the liquid on the top (possible may contain some cobalt atoms). try with concentrated NaCl. best configuration,.... hmm,... I think, two difrent salts or AlCl3 on - and H2SO4 on +. I try a green LED and 3V electric motor,.... work realy good. I use 15 - 20% of H2SO4.

Did you try to recharge the cell ? no,... the Al is in 60 min realy bad damaged in alone in siting in NaOH. With this setup is no option to recharge the cell. I think will possible work,... with Al-GIC/AlCl4-ion l. (aluminium ion electrode in aluminium salt/ionic, DES,...) but this is more complex concept

Also in this project I use a zinc and magnesium. MnO2 - Mg: 2.42V and MnO2 - Zn: 2.40V

[profitis]

Crayex' MnO2 and graphite in H2SO4,'

Alternative is to plate MnO2 direc onto carbon rod from MnSO4/H2SO4 aq. Then use this partially immerse in NaOH sol as exellent oxygen/air catalyst electrode.couple with Zn anode in NaOH and no need for current-limiting saltbridge.makes quite reversible cell aprox 2v.