Re: 2006 PbH2SO4 Battery Project

Wiring, circuits, batteries etc.

Re: 2006 PbH2SO4 Battery Project

Postby cj6s on Fri Jun 27, 2008 1:24 am

Hey there, Windgat. Thanks 4 the invite 2 the forums...This is my first post but it'll probably be quite long. For the benefit of people not interested in lead-acid batts, homemade or otherwise--you should scroll away now...lol
Anyhow, I came across your progress pages and I do have some suggestions. First of all: NEVER short your battery as a means of discharge again. It may explode with lethal force--no kidding--especially in glass jars. And if you are using 33% H2SO4 at the very least you could get seriously burned, if not blinded. And since you use 1mm plates they Will warp and self-short when you get your current output high enough and short them. Also, severe bubbling is very dangerous. It means your charge voltage is way too high. You're right about the bubbles they are hydrogen and the bubbles from the other plate are oxygen gas and mixtures of the two have been known to ignite and explode spontaneously on contact with each other--no spark needed. You are not working in separate half cells right? So they mix in the single glass jar as soon as they are evolved. And even so, when working with these type of things there is always a spark hazard to begin with. You were lucky, man...enough said. Um...reverse charging isn't too good either. The point is to make one plate into lead oxide; by switching polarity while charging, your poor electrodes will be confused as to who is supposed to be positive and who is negative. And, changing polarity under very high voltage charging will not only generate H2 and O2 but mix them for you; add this to hot baths and you have a gas mixture that will supernova if you even give it a bad look...Sorry, I just had to tell you. I was wondering why your experiments ended in 2006 and I was very concerned because I thought the updates ended because your battery did blow up. And you know, there are so few of us concerned with leaving a clean home to our children that we can't even afford to lose one of us. But, that said, there are some useful things that can be done by overvoltage charging. If you do it in an extremely well ventilated outdoor area (and I seriously mean still having a fan blowing away all gas even if outdoors) and stay well away, it is an easy way to concentrate your acid if its specific gravity gets too low. Its very hard to come by acid at over 30-38% concentration and if you want to experiment with ultra high molarity acid electrolytes this may be the only way to get stronger than strong acid. But, caveat, I would not use glass jars to do this. I know you must want to use glass to observe what is happening and that's ok for normal use and charging if you are very careful. But electrolysis is another story. I'd actually use a very weak container so in case of combustion the pressure buildup would be minimal and the acid wouldnlt spray far and any material flying off would be too light to cause real damage. Still, it shouldn't be done at very high voltages. A slight overvoltage is always necessary to charge batteries but you may need to up it a little more to efficiently electrolyze. As long as there are small, visible bubbles the voltage is good so just adjust upward from 2V slowly. And keeping a candle leeward of the fan and apparatus (and you) would be good as it will ignite any gas before the buildup becomes dangerously high.
I read that lead acid batts are now about 90% efficient so about 111% input power to fully charge is a good place to begin. Of course higher inputs may be needed at the beginning when you are training the plates. Just remember to work upwards slowly and to use the bubble indicator to tell you if voltage is too high. And discharge slowly to a maximum of 50% capacity. Actually 20% discharge (80%) remaining is ideal but it will take that much longer to train your plates. But you'll have a top quality home made batt. Electrode spacing is very important. The closer the plates are the less resistance ions have from passing through the electrolyte. This means a faster rate of current flow, so higher amps. Your ides of using a fabric is good. Try to get it as thin as possible. Strike a happy balance between a material that has a thick enough weave so as not to let sediment short you out but "free breathing" enough not to slow down ion flow. (Make sure the fabric hasn't been treated to be water repellent.) The fabric also must not be able to be eaten away by strong acid. By the way, the initial 150mV you read was corrosion voltage. Apparently one of your plates became more electropositive and the other electronegative. Slight differences in plate volume, area and even more trace contaminants in one plate compared to the other will give you a slight potential difference even if they are both of the same metal. (This is partly why metals corrode even if there is essentially only one "electrode") Also, no matter how many cycles you go through, your cells will only produce around 2V each. Voltage is an intensive property, i.e. you would get 2V with 2 electrodes the size of fingernail clippings. What you increase by increasing surface area is amps; and by keeping internal resistance at a minimum you increase overall watt output of your cells. The chemistry is not that complicated but this would be even longer if I put it here. I can't think of a website off hand but a web search on "lead acid battery" with "chemistry" or "electrochemistry" will lead you to sites that explain the chemical processes involved as well as proper charge voltages and discharge loads and levels.
Your misanthropic cell is more complicated. The problem could be minerals in your water--contamination (only use distilled water) or it may be shorted. In fact, I think it may have been your spongiest cell and thus would have warped more during discharge by shorting causing a permanent short. It became a dead cell. The danger there is that dead cells spread the death to their neighbors because they will either pull to much, acting as a heavy load, or not contribute, causing your other cells to overload just to keep up with whatever you load your battery with. (Again, explosions possible, especially if your battery starts putting out major amps.) You need to start from scratch every time a cell is damaged badly--or, at least, train it separately and only connect it when it catches up. Each of your cells should be tested individually frequently to ensure they are at the same voltage and current capacity. This way they will always perform well together in your battery.
The crystals may be glass fiber but may be real as improper charge and discharge methods cause crystal formation on electrodes in secondary cells. I wouldn't use hot baths because this can cause supersaturation of the electrolyte, which, when cooled slowly, will form crystals too. The silvery color on your anode is just the elemental color of lead. At full charge the plate is non-oxidized lead which is naturally silvery and shiny. The color (silver) will remain but the shiny quality should dull as you train your plates. This means that they are getting good and spongy. (Watch out if your cathode goes all silvery and shiny--this can't be good.)
If your battery performance is temperature-dependent it probably means that your acid is too strong. Concentrated acids can become too viscous and this slows down the movement of ions. If you notice that your acid is oily in consistency, thin it down with distilled water. Experiment with different molarities of acid to get the right mix for your plates' condition. Test your acid with a hydrometer. It will tell you the specific gravity of the acid in each cell and you can adjust from there.
Well, I hope this helps a little. If you decide to experiment more with lead acid batteries let me know how it goes. But remember, they are only storage batteries. The power to charge them has to come from somewhere. And, more than likely that power generation is causing some kind of pollution somewhere. Charging your batt with your turbine would be the way to go...then use the batt when there is no wind. Cheers man! 'Til next time......
ceej

Remember: Electricity to power vehicles still needs to come from somewhere...EV's are not the solution, alt nrg is.
cj6s
 
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Re: 2006 PbH2SO4 Battery Project

Postby windgat on Fri Jun 27, 2008 4:50 pm

Wow... ok. Thanks for all your comments.

Shorting batteries: You are right in general about not shorting selad lead acid batteries due to explosion dangers. Not sure what you read on the site but I know that I only shorted the cells out after draining them practically flat by using a load like a motor or light bulb. Also the jars were not sealed so all in all not much danger of explosions there. Glass jars are nice because if due to some reason the acid started to heat up, this can be seen immediately - same for bubbling. But thanks for the warnings! Especially about no spark needed - I didnt know that.

Reverse charging: I was hoping that by alternating plus and minus, one step would form a crystaline porous surface and the other step turn in back into red oxide, with a greater surface area each time.

Seperator: I was going to try cleaning pads mext (spongy, rough, green - usually used for cleaning pots etc.) about 1cm thick, compressed between the rolled plates. I tested some in acid and it did not deteriorate, so it was looking good, but never actually tried it.

I stopped work on this because commerical SLA batteries aren't that expensive, and I wanted to concentrate on the wind charging aspect. It was time consuming making each cell - 12 for my 24V system!

And as you describe, I now run lights off a bank of two 12V batteries, which charge whenever there is wind - no pollution, no costs. The wind is free!
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Re: 2006 PbH2SO4 Battery Project

Postby cj6s on Sat Jun 28, 2008 9:16 am

[[[This is a method for replies I use developed for emails. It ensures that nothing from the original message is forgotten and everything is in context...feel free to use it if you want]]] Wow... ok. Thanks for all your comments.[[[You're welcome; hope there was some useful stuff.]]]
Shorting batteries: You are right in general about not shorting selad lead acid batteries due to explosion dangers. Not sure what you read on the site but I know that I only shorted the cells out after draining them practically flat by using a load like a motor or light bulb. [[[Oh, ok, I thought you shorted them to discharge them--but why do you short them after discharge? Is there any use 4 this?]]] Also the jars were not sealed so all in all not much danger of explosions there. Glass jars are nice because if due to some reason the acid started to heat up, this can be seen immediately - same for bubbling. But thanks for the warnings! Especially about no spark needed - I didnt know that. [[[Well, thats a little safer then, I knew they weren't completely sealed but still, H2 and O2 will mix inside the jars w/ high V charging and can ignite from tiny sparks from the cell itself, especially since they are so close together to reduce resistance. Gas buildup can still occur even if gas can escape through the slits in the plastic lids. Safest thing to do is to charge at proper V, about 14.2 will not allow gassing to occur.]]]

Reverse charging: I was hoping that by alternating plus and minus, one step would form a crystaline porous surface and the other step turn in back into red oxide, with a greater surface area each time.[[[Crystal formation is never good and they usually form during bad discharges anyway, not during charging. With your microscope, if you do notice crystal formation after a charge on either plate check your charging levels as crystals, as far as I know, are always bad. They are sharp and will cut through any separator material or will grow and bridge the separator gap, both causing internal shorts. Just keep charging slowly and slowly discharging until your surface area becomes as large as you can make it.]]]

Seperator: I was going to try cleaning pads mext (spongy, rough, green - usually used for cleaning pots etc.) about 1cm thick, compressed between the rolled plates. I tested some in acid and it did not deteriorate, so it was looking good, but never actually tried it.

I stopped work on this because commerical SLA batteries aren't that expensive, and I wanted to concentrate on the wind charging aspect. It was time consuming making each cell - 12 for my 24V system![[[You may want to experiment with lead foam/porous metal. It is expensive compared to lead plate but has just gargantuan surface areas. You may end up with a 2V cell producing a thousand amps that is the size of your fist and weighing only about 200 grams. Just read up on how exactly to make a battery first so the money is well spent. I mean this is not material to experiment with a great deal. Look for the patents for LA batts online to see how to make one real well. It may be cheaper than a huge heavy 12 batt bank that is store bought (saving on middle man costs/profits) and it'll be easily portable. Plus you get bragging rights...lol...]]] (and may even be able to sell it??? Who knows?)]]]]]]

And as you describe, I now run lights off a bank of two 12V batteries, which charge whenever there is wind - no pollution, no costs. The wind is free! [[[Right, it is free, you just have to recover your construction/ maintenance cost and time input cost (see my reply to post on "free energy".]]]

Overall, I think wind is better than solar since there is wind almost everywhere (and you can even generate your own wind using the sun's heat--yes there are ways to do this). Solar alse remains expensive because of the cost of solar panels (due to the cost of the almost pure materials needed in them). And even if you used homemade parabolic mirrors, say to heat water to steam to run a turbine, you will lose over half the input energy (using the most expensive, hi-tech turbines) converting solar heat to electrical energy (nrg). At least with wind all you lose is about 20% max on turbine friction and charging losses. I'm posting some stuff on my iron batt project...check that out too. I have some questions there about amp readings; maybe you could help me out. Well, hope to hear from you soon, buddy...
cj6s
 
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Re: 2006 PbH2SO4 Battery Project

Postby nobi on Sun Jan 11, 2015 11:25 am

I was going to try cleaning pads mext (spongy, rough, green - usually used for cleaning pots etc.) about 1cm thick, compressed between the rolled plates.......!!!!!!!!!!
kaleem
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