That is why i posted those links. 
The brass iron one looks like it is the best, and it isnât that hard. not super dense but if you are sitting on a bunch of brass and steel for scrap to sellâŚ
The first part is the clean up to get the grease and oxidation off, then you just use electrolysis on it.
Apparently the brass and iron batteries work best with iron oxide if you use a chlorine solution. Not sure if that means you can just rust up an iron plate or if youâd need to compress some oxide together.
What I mean is , spare me all the chemical mumbo jumbo ,and tell me how to build a real life usable storage battery from redally available stuff.
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Edison batteries are the only things that come to mind Al.
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I would kindly disagree, because construction of useful Edison battery is beyond DIY area. I think that the good old copper-zinc Daniell cell - Wikipedia is quite more practical for someone who want to make something ourself
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The Edison Cell is only beyond the DIY arena because of making the Nickle. Otherwise the cell is fairly simple, and you can construct it.
The Daniell Cell from my understanding isnât reversible, you canât charge it.
The Brass/iron battery is based on the so called baghdad battery. It has a really low density, but brass and iron both weigh a lot. I didnât look for âefficiencyâ or if it off gassed, or anything like that. It was on the show mythbusters, and they actually electroplated something with their replica.
There is no archeological evidence to support it being a battery or they did electroplating but could you imagine being in like 280 bc with a pile of lead, making like roman coins and then electroplating gold on it? You would be rich or dead pretty quick.
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Since the chemistry od Daniellâs cell is reversible, so the cell should be rechargeable. It is mentioned in Wikipedia. It might be that charging current must be kept low, which may discourage practical use. But the construction is simple and from common materials readily available on the market or scrapyard.
There is no off gas, no electrode or electrolyte degradation, easy repair, âŚ
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The Baghdad battery used copper, not brass. It also used an acidic electrolyte and not a basic one.
After some research, I have to recall some of my statements.
Daniellâs cell is not rechargeable in its basic costruction with ceramic permeable separator. It is also prone to spontaneous discharge by migrating Cu cations through separator. It might diminished by stable power drawing which coplicates overall design even more. But still, with some invention, viable design could be find and then the availability and price of material would win
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You are right. I will stand corrected.
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I would like to experiment with brass iron base electrolyte though.
Maybe compare it to copper iron acid. I wouldnât even know where to begin on telling how many volts per cell, but I do have a capacity discharge tester.
You just read volts with a multimeter. The youtube guy in the 3rd link is great because he isnât using âproper scientific methodâ and doing everything all perfect. And he goes through a BUNCH of different chemistries.
The Brass/iron battery actually reacts with the copper in the brass. I donât know why they didnât just use straight up copper. I donât know if the zinc helps or not, they donât appear to mention it. And I am looking for someone that replicated it. And -this- may be why we donât see much, but notice in the patent, zinc can be used as the electrolyte, so brass might work better.
The Iron battery has a really low voltage but they do have really good directions on how to build it in their supplemental material.
**on second look the patent appears to be withdrawn in 2012.
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Tom i have watched many of Robert Murray Smithâs videos on batteries. I was left with the impression that the cost wouldnât be any better than mass production batteries when all was said and done. The zink Bromine cells looked the most viable to me but i was looking at an EV tractor application and he hid the trick to make them a gel cell behind his paywall. I wasnât going to subscribe for one video.
Also the Bromine is pretty nasty stuff in high concentrations. In the end i decided the purchased batteries where the best bet. Not that i have made it that far with my small ev tractor project it gets put on the back burner for other projects all the time.
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I didnât even know he had a pay for more information option Dan. I thought he just skimmed the surface of different subjects and still had the time to put out endless videoâs. I have to be in the mood to watch them anyway. His voice and presentation is like nails on the blackboard for me at times.
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I think they are members only videos on his YouTube channel but i would try to contact him before i tried to get that information IIRC he has atleast 2 YouTube channels now.
It has probably been over a year since i watched much of his channel. When he got off batteries and i decided the cost saving where not there for me i stopped watching.
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This guy is showing his own testing if DIY batteries. Most promising is copper positive and steel negative. He wrapped the steel plates with steel wool in a potash electrolyte and it really helped. The first test is that cell, others are the second style he built.
His next test is going to be copper and steel BBs suspended in plastic baskets. That will be very interesting to see.
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That is a pretty good price for anyone in the USA.
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With such a price, who would invest effort into DIY battery of comparable service.
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Itâs like hiring someone to get your wife pregnant Kamil. Somethings you just want to DIY.
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OK, Tom, family affairs aside 
. If I would commit myself to DIY equipment like battery, I would choose the solution which is exhaustively documented, easily constructable with basic tools from cheap abundant materials, preferably obtainable also as DIY. For this sake I would abstain little bit from excellent performance and parameters. All these things direct me to the classical lead-acid battery in deep cycle construction.
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