In my ongoing quest to build the perfect home made battery, today I am testing to find the best electrolyte. To-date I have tried water, salt water, bleach and combinations of the three. So far, with only testing bleach, water and salt, pure bleach has proven to be the best electolyte, but I have a feeling that’s going to change as soon as I do this test with Sulfuric acid. Sulfuric acid is what car batteries, lead-acid batteries, are made with. In fact the sulfuric acid I am using to test with was purchased for about $30USD from Napa Auto Parts as “Battery Fluid, Acid”. That’s what it says on the 5 gallon box I purchased today.
Here are the standards used during this test:
- Electrodes – one copper and one aluminum. I used 1/2 copper pipe about 2 inches long and an aluminum strip that was about 2 inches long by 1 inch wide.
- container – 1.5 ounce plastic reservoirs. I used 8 compartment plastic Popsicle trays bought from Dollar General for a buck.
Using bleach as an electrolyte:
- Voltage – 1.14 volts after about ten minutes.
- Amperage – 12.00 ma roughly using the ma setting and 20m(not the 10amp setting) after about ten minutes. Note that I’m not sure that when not on the 10amp setting that a reading of 12.00 is actually 12 ma.
Using Sulfuric Acid as an electrolyte:
- Voltage – 0.45 volts right away and ten minutes later I got 0.65 volts.
- Amperage – 14.01 right away and ten minutes later amps were reading over what could be read using the red lead on the ma setting, so moved it over to the 10am setting and set the meter dial to 10 amp also getting a reading of 0.02amps which is approximately 3 times more than the bleach produced.
Using Hydrogen Peroxide as an electrolyte:
- Voltage – 0.45 right away and ten minutes later I got 0.62 volts.
- Amperage – right away I had to go to the normal 10amp setting on the dial and the red lead and got a reading of 0.02amps which was the same as using acid after ten minutes. After ten minutes time I got a reading of 18.02 ma using the ma setting for the read lead and the dial turned to 20m.
The Test of Time
The next thing that is important to me is that the electrolyte lasts a good amount of time. So far, I’ve tested a pure bleach battery and it ran for 3-5 days before crapping out because of too much corrosion on the terminals and there was from 1/4 inch to 1/2 inch of sediment in the bottom of the 1.5 ounce containers used for ea. cell.
I will have to report back regarding the Sulfuric Acid and Peroxide results. Coming soon!
The bad news is that I spent $30 on Sulfuric Acid when bleach seems to work better so far. With eight cells in a series, I was only getting up to 4 volts about an hour after wiring the battery. Using the same battery with bleach, I was getting 10-12 volts DC, so bleach is the clear winner here thus far. I’m still waiting for the results of time on the Acid battery and peroxide battery cells.