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Author: Subject: Homemade Car batteries
tito-o-mac
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Does anyone know how to make a homemade car batery (just the chemicals), cos' I have already got all my other apparatus ready:corrosive-proof container,crocodile cables etc?
roamingnome
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potenionally this is an intersting topic becuase the electric car needs to be in the hands of the people!

unfortunitally there are many differnt types batteries

i promote the concept of the sodium sulpher battery.. it must operate at at high temp though to keep sodium molten.. but the charge is supposly good.... and its lighter. its also appears to be "homemade" possible...

as far has your deal .. lead...and battery acid from a auto parts store will get you in the right direction...

also since this was posted in biochemistry forum ... you might be intersted in biochemical batteries like the electric eel or a good fish muscle battery

insect flight muscle is also the bomb...
YT2095
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Ill give you a tip, dont use Roofing lead either, Ive tried it and its crap for large scale work, but yeah alternate layers of GOOD (pure) lead sheet and rock wool in a suitable container and the H2SO4 ~35% will work as Project sure

\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
tito-o-mac
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Does something of strong acidic nature or strong acid based work for car batteries?
Nerro
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#261501 +(11351)- [X]

the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally

courtesy of bash
not_important
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Or research "Edison battery", "zebra battery", and just plain "how batteries work"
alancj
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 Quote: Originally posted by roamingnome i promote the concept of the sodium sulpher battery.. it must operate at at high temp though to keep sodium molten.. but the charge is supposly good.... and its lighter. its also appears to be "homemade" possible...

I would promote the sodium/nickel chloride battery. A.K.A. the Zebra battery as not_important mentioned. I think it has all the advantages of the sodium/sulfur, but with none of the disadvantages. It does use nickel, but at a rate of 5 times less than an equivalent NiMH or NiCd. One could use iron or copper instead of nickel at the cost of energy density. Both batteries require the alpha Alumina ceramic membrane, so I don't know how that can be homemade.

The Edison iron nickel alkaline battery would be the easiest for the amateur from what has been mentioned IMHO.

-Alan
tito-o-mac
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Wait wait wait... There are quite a handful of you all "promoting" different battery solutions. Can any of you explain the advantages (e.g. the voltage etc ) and how to obtain it?
not_important
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Depends on the target application. Voltage is easy, just add cells in series. Other issues are energy density = watt-hours per unit volume and unit weight, depth of discharge tolerated, self discharge rate, number of discharge/charge cycles supported, and so on.

Start with Wiki and Google searches, plenty of information out there to read, no sense retyping it here.

The lead-acid battery is pretty well developed. While the basic battery can be made at home, a DIY version of the store-bought battery would be difficult. You have to make the plate alloy, then make the actual grid plates, fill them with the paste, assemble them with the separators (which ou also would have to make), and seal up the unit. You'd likely have to make dozens of attempts before you managed to make a battery that approached the effectiveness of a standard manufactured one.

Start here for a bit more detail

[Edited on 19-7-2007 by not_important]
tito-o-mac
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Construction of battery

Plates
The principle of the lead acid cell can be demonstrated with simple sheet lead plates for the two electrodes. However such a construction would only produce around an amp for roughly postcard sized plates, and it would not produce such a current for more than a few minutes.

Gaston Planté realised that a plate construction was required that gave a much larger effective surface area. Planté's method of producing the plates has been largely unchanged and is still used in stationary applications.

The Faure pasted-plate construction is typical of automotive batteries. Each plate consists of a rectangular lead grid alloyed with antimony or calcium to improve the mechanical characteristics. The holes of the grid are filled with a mixture of red lead and 33% dilute sulphuric acid (Different manufacturers have modified the mixture). The paste is pressed into the holes in the plates which are slightly tapered on both sides to assist in retention of the paste. This porous paste allows the acid to react with the lead inside the plate, increasing the surface area many fold. At this stage the positive and negative plates are identical. Once dry the plates are then stacked together with suitable separators and inserted in the battery container. An odd number of plates is usually used, with one more negative plate than positive. Each alternate plate is connected together. After the acid has been added to the cell, the cell is given its first forming charge. The positive plates gradually turn the chocolate brown colour of lead dioxide, and the negative turn the slate gray of 'spongy' lead. Such a cell is ready to be used.

Many modern manufacturers use pastes in the plates made directly from lead dioxide and lead, eliminating the forming process. Once acid is added, the cell is ready for use.

One of the problems with the plates in a lead-acid battery is that the plates change size as the battery charges and discharges, the plates increasing in size as the active material absorbs sulphate from the acid during discharge, and decreasing as they give up the sulphate during charging. This causes the plates to gradually shed the paste during their life. It is important that there is plenty of room underneath the plates to catch this shed material. If this material reaches the plates a shorted cell will occur.

Separators

Separators are used between the positive and negative plates of a lead acid battery to prevent short circuit through physical contact, mostly through dendrites (‘treeing’), but also through shedding of the active material.

Separators obstruct the flow of ions between the plates and increase the internal resistance of the cell.

Various materials have been used to make separators:

wood
rubber
glass fiber mat
cellulose
sintered PVC
microporous PVC/polyethylene.
An effective separator must meet a number of mechanical properties. Permeability, porosity, pore size distribution, specific surface area, mechanical design and strength, electrical resistance, ionic conductivity, and chemical compatibility with the electrolyte. In service the separator must have good resistance to acid and oxidation. The area of the separator must be a little larger than the area of the plates to prevent material shorting between the plates. The separators must remain stable over the operating temperature range of the battery.

In the battery service condition the following reaction can be shown :

PbO2 + 2H+ + SO4-2 = PbSO4 + H2O + ½ O2
PbO2 + (oxidizable separator material) + H2SO4 = PbSO4 + (oxidized material)

[Edited on 19-7-2007 by tito-o-mac]
tito-o-mac
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Gee, I didn't know it was so complicated! I thought I only needed the acids.
Oh yeah, here's some information about the voltage:

The following are general voltage ranges for six-cell lead-acid batteries:

Open-circuit (quiescent) at full charge: 12.6 - 12.8 V
Open-circuit at full discharge: 11.8 - 12.0 V
Loaded at full discharge: 10.5 V.
Continuous-preservation (float) charging: 13.8V for gelled electrolyte; 13.5V for AGM (Absorbed Glass Mat) and 13.4V for flooded
All voltages are at 20C, and must be adjusted for temperature changes.
Float voltage recommendations vary, accordig to the manufacturers' recommendation.
Precise (+/- 0.05V) float voltage is critical to longevity; too low (sulfation) is almost as bad as too high (corrosion & electrolyte loss)
Typical (daily) charging: 14.2 - 14.5 V (depending on manufacturer's recommendation)
Equalization charging (for flooded lead acids): 15 - 16 V
Gassing threshold: 14.4 V
After full charge the terminal voltage will drop quickly to 13.2 V and then slowly to 12.6 V.

I bought a 5 pure lead plate from a local hardware store! 2 litres of sulphuric acid coming tmr!

I read about this: If you have any metal fillings in your teeth, avoid making tooth contact with any different metal! If you accidentally touch a bit of aluminium foil, say, with the filling, the two metals and your body fluids, saliva and blood, will send a small, but unpleasant electric current through the tooth and jangle its nerves. Damn I've got braces!

One question: How dangerous is this project? I've read about the recharging car battery explosion thing, how would you rate it upon 5?

[Edited on 19-7-2007 by tito-o-mac]
tito-o-mac
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Damn! My dad says it's not safe to keep 2 litres of sulphuric acid, especially under the watchful eyes of the police...
gregxy
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If you just want to demonstrate a lead-acid battery just get
two lead plates suspend them 1/2 inch apart in a dilute H2SO4 solution and charge it for a while. (We did this in high school). You will get 2V per cell and probably a few mA hours of capacity. If you want a "good" battery to actually power things, them you will do much better to go out and buy one. Replacement UPS batteries are great for this.

The main danger is spilling the acid on yourself. Or if you buy a UPS battery don't short it out.

If you want a really good battery in terms of energy density and ability to deliver high power check out the Li based ones used in electric model airplanes or in the high end cordless drills. (of course these are expensive)

[Edited on 20-7-2007 by gregxy]
dann2
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Hello,

Lindsay publications do a 'Lost Technology series' of books. They republished 'Storage Batteries Simplified'. This explains how to make Lead acid batteries and what makes them work.

There is a battery system coming into use for large wind generator systems based on Vanadium.
The power is stored in the electrolyte, not on the plates. The electrolyte consists of Vanadium in two valency states. One valency state when has 'power', the other has not.
The plates are only used to draw power to and from the electrolyte (the power store). The amount of electrolyte can be small or hugh. It can be in a sererate storage compartement if you want a battery with large capacity and pumped to the plates when power is wanted. The Vanadium is not toxic and relatively (I think) cheap.

Dann2
cyclohexane
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 Quote: Originally posted by roamingnome potenionally this is an intersting topic becuase the electric car needs to be in the hands of the people! unfortunitally there are many differnt types batteries i promote the concept of the sodium sulpher battery.. it must operate at at high temp though to keep sodium molten.. but the charge is supposly good.... and its lighter. its also appears to be "homemade" possible... as far has your deal .. lead...and battery acid from a auto parts store will get you in the right direction... also since this was posted in biochemistry forum ... you might be intersted in biochemical batteries like the electric eel or a good fish muscle battery insect flight muscle is also the bomb...

i remember reading that early experments with electricity were accomplished by means of tanks of electric eels and two copper rods in the water...pissing the eels off would get them to make juice. i belive they can put out 600k volt bursts in attack mode, and maybe 200k in "find" mode normally. iam not sure of amprage. ( read that at the aquarium looking at em)
so could u,with enough tanks of eels and storage batterys power your home with eels?
also i have a pet theroy that houshold urine could be diverted into a concrete silo that would function as a large "wet" cell and produce power......
....any thoughts about these ideas?

[Edited on 7-1-2008 by cyclohexane]
12AX7
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As I recall, eels produce voltages in the hundreds, not hundred thousands. It would be mighty difficult to produce that kind of voltage in a conductive medium like water. I think current is roughly an amp or so. Notice that corresponds to a peak power of about 1HP, impressive for an animal of that size.

Waste in a silo, hmm I'm reminded of The Simpsons Movie.

Tim

Chemistry section: http://webpages.charter.net/dawill/tmoranwms/Chemistry.html

"I could take measurements, but why bother? Science just slows down chemistry!" - Myself
cyclohexane
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Hmmmm ill have to webserch that....was sure it was hundreds of thousands at low amprage.....just like a tazer.......but i could be wrong.
lol...hopefully not like the simpson movie,lol
more like a underground concrete cylinder....lol urin would be a mild base ( or maybe not if its uric acid?) so it might not make that much current. ...would be cool to power the house from some big tank'o crap tho....
indigofuzzy
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from http://en.wikipedia.org/wiki/Electric_eel:

In the electric eel, some 5,000 to 6,000 stacked electroplaques are capable of producing a shock at up to 500 volts and 1 ampere of current (500 watts)

SAVE THE MALES!!!
(www.noharmm.org)

The home-made linear peristaltic vacuum pump: Science\'s best abdominal workout!

 Sciencemadness Discussion Board » Special topics » Technochemistry » Homemade Car batteries Select A Forum Fundamentals   » Chemistry in General   » Organic Chemistry   » Reagents and Apparatus Acquisition   » Beginnings   » Miscellaneous Special topics   » Technochemistry   » Energetic Materials   » Biochemistry   » Radiochemistry   » Computational Models and Techniques   » Prepublication   » References Non-chemistry   » Forum Matters   » Legal and Societal Issues   » Whimsy   » Detritus   » The Moderators' Lounge