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.

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 ...   

Quote from: lasersaber on June 25, 2010, 11:08:43 AM
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.

Quote from: PeteIdl4 on June 25, 2010, 01:51:11 AM

@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. 

thank you,

jeanna

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.

Quote from: lasersaber on June 25, 2010, 11:08:43 AMI 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