Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: Working Air Battery  (Read 221307 times)

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: Working Air Battery
« Reply #90 on: June 24, 2010, 05:21:04 AM »
Hi everybody.
It seems a good day to make another air battery follow up video, so I did.

http://www.youtube.com/watch?v=n9FVnfPoXaY

I changed the jt circuit to one with 3 white leds on the secondary and I can still light up the one that was taped without any extra water.
I added water in the video anyway and it did get brighter.
The 1 inch which has very little tape over it got very dry in spite of the humidity and the epsom salts added to the cloth, so I had to spray it, but then it got very bright.

I like the flexibility of this battery.
In fact the one that is more open and can dry out can be allowed to stop which I assume will add to its over all life. The in-use life will be the same, of course.

I am not doing the constant run test that lasersaber is doing.
I am just letting it go on then off and again to see how it does.

The one I made on the carbon welding rod broke apart a long time before the mg ribbon dissolved, so I believe this is an important piece to follow too.

jeanna

conradelektro

  • Hero Member
  • *****
  • Posts: 1842
Re: Working Air Battery
« Reply #91 on: June 24, 2010, 01:12:14 PM »
I did some tests with a salt water cell (aluminum – salt water – copper). See the attached photos. The cell gives initially 2 mA but drops after an hour to 0.04 mA (40 micro amperes). The voltage is about 0.43 Volt. So, such a cell is not very good, something is missing.

The aluminum - salt water – copper cell:

- Glass test tube, diameter 30 mm, height 200 mm, contains about 100 mL saltwater

- Salt water: 500 mL tap water with 35 grams of table salt (double seawater salt content, more salt does not help)

- Aluminum sheet from soft drink can, about 120 cm2 (about 18 square inches)

- About 5 meter blank copper wire wound on 10mm plastic tube

- About 0.43 Volt, 40 micro amperes (0.04 mA), initially up to 2 mA

Remarks:

- 4 of the above salt water cells in series (about 1.72 Volt, but sink to about 1 Volt under the JT load) drive two red LEDs in series with special JT circuit (50 mm air core, 20 turns bifilar winding, swings at about 1.2 – 1.5 MHz)

- when the cell is filled with “fresh” salt water it will develop up to 2 mA at 0.43 Volt for up to an hour, then the output drops slowly over hours to 0.04 mA (this can be reproduce by refilling with “fresh” salt water)

- since refilling with “fresh” salt water increases the output, it seems that something is used up, which I think is oxygen; therefore the “wet paper wraps” are better, because oxygen from the air can enter

Update on the aluminum - tile cement – copper cell:

Air can enter the porous tile cement, and this may be the reason why my “aluminum – tile cement - copper cell” is giving 0.3 mA at about 0.8 Volts already for four weeks. Every few days the tile cement needs a little humidity either from damp air or from placing it in water for a few seconds, which will give the necessary electrolyte. The tile cement seems to be a good “wet paper or cloth” (it looks dry, but some humidity must be present to function).

Conclusion so far (including what I see from the many good posts in this thread):

The concept of “air battery” really needs “air” and some moisture as electrolyte. The air (oxygen) keeps it going, while a little moisture keeps the electrons flowing.

Greetings, Conrad

old man

  • Newbie
  • *
  • Posts: 20
Re: Working Air Battery
« Reply #92 on: June 24, 2010, 05:16:59 PM »
hay everyone new on here like your air batt looks good got to do that one



conradelektro
 just used aluminum can and copper wire and salt water and getting 1.5 volts dontno about ma it been going for 5 days now and that just two cans  i am going for a week and then i and going to and do  12 cans and see what i get will let you all i think i can get 12 volts out of it no later



old man

Hugo Chavez

  • Full Member
  • ***
  • Posts: 114
Re: Working Air Battery
« Reply #93 on: June 24, 2010, 05:36:12 PM »
hay everyone new on here like your air batt looks good got to do that one



conradelektro
 just used A can and copper wire and salt water and getting 1.5 volts dontno about ma it been going for 5 days now and that just two cans  i am going for a week and then i and going to and do  12 cans and see what i get will let you all i think i can get 12 volts out of it no later



old man
WOW....... LOL........ 

DrZoidberg

  • Newbie
  • *
  • Posts: 12
Re: Working Air Battery
« Reply #94 on: June 24, 2010, 08:05:27 PM »
I did some tests with a salt water cell (aluminum – salt water – copper). See the attached photos. The cell gives initially 2 mA but drops after an hour to 0.04 mA (40 micro amperes). The voltage is about 0.43 Volt. So, such a cell is not very good, something is missing.

Strange. Even a small copper coin and a small piece of aluminum foil give 2ma, so your initial current should be a lot higher then that.
Is your aluminum coated with plastic?
BTW. You can increase the voltage to 1.4V by adding a tiny amount of NaOH (drain cleaner). But it will dissolve the aluminum. The more you put in, the higher the load can be before the voltage drops but the aluminum will dissolve more quickly.
Don't put a large amount of NaOH in. It will bubble like crazy and can get quite hot.

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: Working Air Battery
« Reply #95 on: June 24, 2010, 09:13:42 PM »
...
Is your aluminum coated with plastic?
BTW. You can increase the voltage to 1.4V by adding a tiny amount of NaOH (drain cleaner). But it will dissolve the aluminum. The more you put in, the higher the load can be before the voltage drops but the aluminum will dissolve more quickly.
Don't put a large amount of NaOH in. It will bubble like crazy and can get quite hot.
And it will be producing H2 gas when it dissolves the Al. So, be careful with any flames if you get a lot of bubbles.


@conrad,
I like the cement idea. I found it worked for a while myself, and perhaps you have found the trick to keep it active.
the alkaline neture of the cement is what makes the H2 gas form and it does this with magnesium too. I am wondering if this "air battery" that Lasersaber has described might not work for a longer time if cement is placed between the mag ribbon and the copper pipe or carbon rod.
I may mix up some cement soon and try this.

Once the cement is mostly dry and not so actively alkaline, it might be a great interface material, but before it dries it will not, IMO.

I have been playing for a week with this stuff and what I see there is a oxidation going on by the water with some kitchen salt on the magnesium ribbon (see pictures down under)

BTW
Welcome and thanks for the pix
ugly!
You have inspired todays tests.  :D

I am testing a couple of electrolytes today.
I used epsom salt the other day and I am not seeing the kind of degradation that others who have used table salt have.
So, I will see what happens and let you all know.

jeanna


jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: Working Air Battery
« Reply #96 on: June 25, 2010, 01:25:29 AM »
I have some preliminary pix of the difference between NaCl and MgSO4 as electrolyte.

Just so you know what I did, I measured off equal amounts of mag ribbon and copper wire, made a spiral of each which I hung over the edge of the glass. I had to wrap the copper with something to prevent contact, so I used some gauze.
The solutions are approximate and they should both be saturated solutions which means there is a little undissolved salt in the bottom of the glass.
The refined sea salt = NaCl gave a voltage/amps reading of
1.49v
27mA

The epsom salts = MgSO4 gave a reading of
1.58v
20mA

They started at very close to the same time, but as you can see, there are way more bubbles on the Mg ribbon in the NaCl than in the MgSO4

They are big, but they pop the way H2 pops but there is no orange color at the point of the flame.??

Have a look.
First is the NaCl second is the MgSO4

jeanna

I just realized that it was dumb and risky to pop the bubbles with a flame so very close to the magnesium ribbon.
Please don't do this yourselves anybody...you may not be as lucky as I!!
« Last Edit: June 25, 2010, 03:15:58 AM by jeanna »

PeteIdl4

  • Newbie
  • *
  • Posts: 21
Re: Working Air Battery
« Reply #97 on: June 25, 2010, 07:51:11 AM »
Nice work everyone, I've been busy for a few days, it's nice to see everyone contributing and forging ahead.

@Conrad,
I really like the design of those aluminum and copper cells, really great job. I agree that something seems to be leaving the cell that diminishes the power, not sure if its the oxygen that's being depleted, it might also be the hydrogen also as it appears in Jeanna's test of different electrolytes. Keep up the good work Conrad we'll figure it out.

@Jeanna,
Nice job on the electrolyte tests. This is very useful information to know. Just one question, what's the time frame on those pictures?

@All,
I have also made a recent update on my air batteries to show they're all still alive and still performing well. Also it's my first video upload, so it's a test on that as well. It's broken into two parts, my camera was giving me some difficulties so it cut off towards the end of the first video.
Part 1 http://www.youtube.com/watch?v=1Hc-xyTFFGk
Part 2 http://www.youtube.com/watch?v=eLry46yKcmI

Hopefully I'll finish the new ones I'm working on this weekend, I'll be sure to keep you guys(and gal :)) posted. Once again keep up the good work to everyone and thanks for sharing the info.

-Pete

conradelektro

  • Hero Member
  • *****
  • Posts: 1842
Re: Working Air Battery
« Reply #98 on: June 25, 2010, 01:23:19 PM »
@DrZoidberg

Quote
Strange. Even a small copper coin and a small piece of aluminum foil give 2ma, so your initial current should be a lot higher then that.
Is your aluminum coated with plastic?

When I fill the tube with "fresh" saltwater (the concentration of salt does not matter, equal or more than seawater concentration which is 3.5%) I get a very high current (up to 20 mA) for a short time (some minutes), for up to one hours I get up to 2 mA and then it drops to 0.04 mA. (Aluminium - salt water - copper in the test tube, as in the photos I posted above).

The aluminum sheet from the soft drink cans has been scrapped on both sides with sand paper (with a hand held machine) till only raw aluminum is visible.

Greetings, Conrad


conradelektro

  • Hero Member
  • *****
  • Posts: 1842
Re: Working Air Battery
« Reply #99 on: June 25, 2010, 02:37:16 PM »
@ Pete (PeteIdl4), Jeanna and all

Great videos, Pete! Carbon and magnesium seem to be the best; also in combination with copper, and carbon - magnesium seems to be top. The little carbon - magnesium cell is surprising.

Because adding water (as Pete shows in his video) helps and as Jeanna shows in here water containers, magnesium and copper also work great in a "wet cell".

I wounder what keeps aluminum in my test tube cells from reacting long term (not only for a short time after filling the tubes with fresh salt water)? It can not be the copper, because Jeanna uses copper in her wet experiment with magnesium ribbon.

May be aluminum is just not as active as magnesium. Magnesium is almost as fast as sodium (Natrium), therefore it deteriorates rather fast (pieces breaking off).


Bagdad Battery

I also did some tests with a Baghdad Battery (see http://en.wikipedia.org/wiki/Baghdad_Battery ) which simply means I used citric acid instead of salt in my test tubes.

With aluminium and copper (in the test tubes) citric acid gives about the same results as salt (impressive for a few minutes, pretty good for an hour, but then amperage drops like in salt water to less than 0.1 mA). Different concentrations of citric acid did not help.

I plan to make a real Baghdad Battery with iron and copper (and citric acid). May be iron reacts better than aluminum (although it will give a lower voltage).

When I think about it, steel or iron rusts (corrodes) much faster in seawater than aluminum, or am I mistaken?


Tile cement cell

I did not give up the tile cement and will build more and bigger tile cement cells after my excursion into wet cells comes to an end. The aluminum - tile cement - copper cell serves as a reference (which I could not yet beat with a wet cell).

I know that magnesium and carbon beats everything, but I want to exploit readily available materials (like aluminum, steel and copper) first. And only when that becomes hopeless I switch to the super stuff (which will not be available in an crisis situation). Salt and citric acid are rather easy to get (seawater and many fruits).


Seawater

I really like seawater (saltwater), if one can use that, it would become simple. Even with a bulky set up, it would be great as an emergency battery.

O.k., I make a steel - saltwater - copper thing right now, stay tuned. I will wrap one metal in a cloth as Jeanna did, then the build stays simple.


Greetings, Conrad

lasersaber

  • Full Member
  • ***
  • Posts: 179
Re: Working Air Battery
« Reply #100 on: June 25, 2010, 05:08:43 PM »
I always found that the way to get higher milliamps was to use long lengths of wire or magnesium ribbon.  It's of utmost importance that the wire or ribbon never touches its self.  Check out my thread over here for more info: http://www.overunity.com/index.php?topic=8640.0   Because of what I learned doing these experiments, if I wanted to make a battery with a coke can I would probably cut it into a ribbon and wind it around a carbon rod or copper pipe as in my current designs.  There may be other, better ways but so far this is what I have found to work best.

These new air batteries grew out of my findings doing earth batteries.  I then decided to figure out a way to utilize the long wire effect in a small portable configuration.  That is why I started building NS coils as his design seemed to integrate this.  I just got tired of having to wet them down every few days.

My batteries are still going strong.  They are much brighter then in my last video as the air humidity has gone up some.  I may be very wrong, but I think that the salt crystals are helping to keep the current flowing when they dry out on low humidity days.  The water I initially dipped them in was heated and oversaturated with salt.  I did this to try and get them to grow crystals.  So far it has been working well.  I have not had any problem with the salt crystals shorting out the ribbon.  We really need to do a lot more long term tests to know what really works best.

Everyone remember that my first air batteries had no salt added and they ran fine for weeks.  I just had to use twelve of them to light one LED.

My goal is to keep these running without adding any water.  That is probably the key to super long battery life.  I am looking forward to winter when I will have low humidity.  I think that if I can get one to run all winter under load with out adding water then I'll be all set for the next step.  All you folks who have lower humidity please keep in mind that you have a great opportunity to test these.  In my earlier tests I made air batteries that did not even show any milliamps but when I connected six of them together I had over six volts and I could light an LED.  You may have to make more air batteries or larger air batteries but at some point you should be able to get them to run an LED or pulse motor off air humidity alone.  At that point start your long term tests.  I hope that you are a very patient person because if you have any success you may have to wait a very long time for your tests to run their coarse.

stephenafreter

  • Jr. Member
  • **
  • Posts: 54
Re: Working Air Battery
« Reply #101 on: June 25, 2010, 08:26:20 PM »
After bathing in the sea/ocean, the clothe is very long to dry compare to wet with tap water.
Rain water is also harder to dry than tap water.

Thanks for sharing this info, I am trying this concept of self made batteries.
I was thinking of my friends in Cambodia, there many people don't have light at home.

I am thinking about the cheapest design possible, like using charcoal and aluminum foil.
Like putting a layer of alu foil in a tube form, then the cotton clothe, and then introducing the charcoal powder in the center, then compressing it.

Of course we need another design to use a long wire as electrode ...

What I am thinking about is a recyclable version.
For example using a copper pipe in the center and an aluminum wire on the outside. When corroded we could disassemble the all thing, and scratch the corrosion of the pipe and wire with sand paper.
Then it could run for another cycle ...   

jeanna

  • Hero Member
  • *****
  • Posts: 3546
Re: Working Air Battery
« Reply #102 on: June 25, 2010, 09:19:41 PM »
I always found that the way to get higher milliamps was to use long lengths of wire or magnesium ribbon.  It's of utmost importance that the wire or ribbon never touches its self.  ...
I agree with you.
When I tried to "use" the 2 batteries in the salt solutions, I found that even though the meter showed that they had over 20mA each, they could only pulse a jt circuit with a red led on the secondary.
When I put the 2 in series they readily lit the jt circuit with white leds and did so with good brightness.

Quote
..  I just got tired of having to wet them down every few days.
The humidity was 49% yesterday and 55% today, so I can say that this is still too low to sustain enough moisture in the ones with exposed cloth or paper. The one with tape is still working fine since being wetted 2 days ago on the video.
Quote
...  I may be very wrong, but I think that the salt crystals are helping to keep the current flowing when they dry out on low humidity days.  The water I initially dipped them in was heated and oversaturated with salt.  I did this to try and get them to grow crystals......  We really need to do a lot more long term tests to know what really works best.

this is a very interesting thought that the crystals could make it work better.
Yup, more time to know.

Quote
..... All you folks who have lower humidity please keep in mind that you have a great opportunity to test these.  In my earlier tests I made air batteries that did not even show any milliamps but when I connected six of them together I had over six volts and I could light an LED.  You may have to make more air batteries or larger air batteries but at some point you should be able to get them to run an LED or pulse motor off air humidity alone. 
I am willing ( delighted) to try this.
Since I am having good results with the copper tubing, I will continue to use that, and I will make some to put in series. (somehow, I missed that they showed NO mA!)

I used mag sulphate as the salt because I thought it would help to have magnesium in the salt. I wonder if the mg crystal will help better than Na.
In the glass jar controls test, the mA is lower with the mgSO4and the bubbles are much slower even today.

Thanks for your good work.
I find it very inspiring.


@Jeanna,
Nice job on the electrolyte tests. This is very useful information to know. Just one question, what's the time frame on those pictures?


-Pete
those pix were within a couple of hours. I will check later this afternoon at around 24 hours.
I intend to let them run down to where they do not produce any more then weigh them and see what that shows if anything.
That will be next week or later, I am sure.  :D

thank you,

jeanna

DrZoidberg

  • Newbie
  • *
  • Posts: 12
Re: Working Air Battery
« Reply #103 on: June 25, 2010, 10:13:30 PM »
I think it would be great to have an emergency power supply e.g. in case of a long lasting black out or when you are camping somewhere.
I know there are gasoline powered generators but I was looking for something I could use inside.
So an aluminum air battery seems like a great choice. It's small, silent and relatively clean.
But that means the battery needs to be powerful enough to run the most essential appliances (fridge, laptop). A few ma is not gonna cut it.
This battery looks nice
http://www.youtube.com/watch?v=YwT-ONznU5I

They are using some special air cathode to get decent performance.
I found a company that makes air cathodes
http://www.electric-fuel.com/airelectrode/index.html
but I have difficulties finding places to buy the stuff
I only found this so far http://www.alibaba.com/product-free/103337003/air_diffusion_electrode.html
But it says there the service life is only 1000 hrs. That seems a little short.
However it should make a pretty powerful battery. The description says it supports 200mA/cm^2 and it'S 800 cm^2 in size so that should give me 160A.

PeteIdl4

  • Newbie
  • *
  • Posts: 21
Re: Working Air Battery
« Reply #104 on: June 25, 2010, 10:53:55 PM »
I always found that the way to get higher milliamps was to use long lengths of wire or magnesium ribbon.  It's of utmost importance that the wire or ribbon never touches its self.  Check out my thread over here for more info: http://www.overunity.com/index.php?topic=8640.0   Because of what I learned doing these experiments, if I wanted to make a battery with a coke can I would probably cut it into a ribbon and wind it around a carbon rod or copper pipe as in my current designs.  There may be other, better ways but so far this is what I have found to work best.

I agree a wound design always seems to outperform any other design I've tried in the past. I definitely think this is a step in the right direction.

Quote
..... All you folks who have lower humidity please keep in mind that you have a great opportunity to test these.  In my earlier tests I made air batteries that did not even show any milliamps but when I connected six of them together I had over six volts and I could light an LED.  You may have to make more air batteries or larger air batteries but at some point you should be able to get them to run an LED or pulse motor off air humidity alone. 

I will also try this. I've noticed that on my longer poles once they've dried for a few days they still give off a reading of about 1.4 volts at about 80-120 microamperes as I mentioned in my video. I just checked the aluminum and carbon one, which i haven't touched since i put it together(about a week ago). I was quite surprised, the readings show a little over half a volt at 22uA as you can see by the pictures. More long term tests need to be done, but this does seem to confirm Lasersaber's findings.

@Jeanna,
Thanks for the info on those pictures and tests. I'm really interested to find out your results. Please keep us posted. Thanks again and keep up the good work.

-Pete