Low energy Input, mass hydrogen output methods in use.

[BEMET]

Nickel does not react to KOH

[zendog]

I don't think stainless steel reacts with KOH neither

Read somewhere that nickel has a +1.91 (pauling scale)
Don't know the figure for stainless
I for one would be happy to get away from sulphuric acid and lead - both are nasties

[btrautman]

Forgive me if this is understood by all, since I am new here.

In basic lead acid battery operation we have two plates for each cell. There are about 4 or 5 different lead oxides that are used in plate making. These oxide pastes once applied to a plate grid, are then electrochemically converted to lead and the other to lead peroxide. Trade jargon for this process is called formation. Plates are then suspended in sulphuric acid solution and then run through a series of conditioning charges and discharges before the battery is ready for use.

As I mentioned before, plate gride uses antimony or calcium for strength. Antimony had the side affect of increasing hydrogen outgassing that wasn't forseen.

How does a lead acid battery actually work......We have sulphuric acid then when added or "disolved" in water H2SO4, the acid breaks into two hydrogne ions each having a charge of +1 and a sulphate molecule of SO4 having a charge of -2. These charges add up to zero and all is fine.

When the battery discharges, the sulphate ions are free to travel to either plate. At negative plate the ions combine with the neutral lead atoms and form lead sulphate. The lead atom gives up 2 electrons gaining a +2 charge which is neutralized by the -2 electrons of the sulphate ion. The two free electrons flow through the plate and out the battery terminal into the circuit, etc.

At the positive plate the free hydrogne ions extract the oxygen from the lead peroxide. Four Hydrogen ions H+ capture two oxygen atoms O- to create two molecules of water. The lead atom left behind has lost two oxygen atoms. The two electrons coming back into the battery and a sulphate ion from the electrolyte combine with the lead atom neutralizing it and forming lead sulphate. As time goes on, both plates become lead sulphate..as this process continues, electrical potential reaches zero between the two plates and the reaction will pretty much cease. Remember at the positive plate acid becomes water and the lead peroxide is used up.

Now how would or could we modify this construction to outgas hydrogen by modifying the plate composition and/or the electrolyte used? I'll put a few ideas in another message...I wanted to lay the groundwork first....

Thanks,
Bob

[Orange_Crusader]

We can change between acids (sulfuric, hydrochloric, nitric, any strong acid) fairly easily, with some changed in amounts of chems and such, since acids give up hydrogen when they react, as opposed to bases, which attract hydrogen when they react, to form a hydroxide compound and water.

With proper safety measures, we should be fine. I don't think we'll use lead, since it won't offgas much (not what we want), but sulfuric seems like a decent choice for an acid, since it's one of the stronger ones. Better sulfur fumes than chlorine fumes (hydrochloric), or NOx (NO2, N2O4, etc. from nitric acid).

Has anyone seen any figures (patents, experiments, etc.) that hint or list how much hydrogen a common edison cell will offgas over a period of time? Unless we can, or absolutely have to, I'd like to avoid having to stack 20-40 cells (side by side, and in two layers) to get any appreicable hydrogen. It's doable, but I'd like a decent amount of hydrogen per, let's say cubic foot of cell. Having one cubic foot of hydrogen per cubic foot of cell would we very nice, even 1/2 cubic feet per cell per minute would be nice, since one cubic foot of cell is a comparably very small space (1x6x2, to give one idea, and that's very, very small. I don't expect it to do that well, seeing our limits with materials, but we'll see).

I'll (slowly) start work on a "master" list of chem combinations, volatge differences (battery function), volt/amp per gram figures, etc. and post them here. it'll be mostly copy/past work, except finding good chem combinations, figuring compounds made, solubility, etc. Any particular chems to put on there? Zinc, Calcium, copper, etc. will go on there, as well as a few others chosen from the chart posted by BEMET (forgot it was there, I'll copy/paste that into MS word to make it more legible).

[WaterFireHO]

Orange... and All

I just found (and Got) Timbies "Elements of Electricity" 1stEdition on Ebay... when it shows up I will see if it has any different different info. in it than what is already Posted. If so I will Post for all !

Also found a bunch af fairly old Chemestry Books @ the GoodWill.

And have a couple of Chemestry Programs to Play with... I will see if they can predict some Results for different combinations. (Got anything Particular you would like me to try?)


Oh and just a thought....
When Alaska mentions SHORTING it Out...
do you suppose since the basic Metals he is refering to are in Chemical form, he could just be putting them together along with a catalyst then adding electrodes to take advantage of the electrical potential (Load) and the regeneration (electroplating)...

[AntDavison]

errata 25:10 1.75v over 5.5hours (25A/100Ah) should read 1.775v over 5.5hours

=

The Edison/IronNickel cell, i understand also has a higher internal resistance compared to a LeadAcid type meaning the LeadAcid could supply higher currents.

The Edison cell, invented c.1900 satisfied only the ignition and lighting requirements of a InternalCombustion automobile, and a power source for ElectricalVehicles. EV's were popular in many city area's with a 40% marketshare. In France, EVs achieved distances over 250km / 150miles before needing recharging. From the invention of the starter motor, c.1910, IC vehicles, always more popular and useful in rural areas, began their domination. They had more power and now easy starting ... if you had a LeadAcid battery. So the Edison cell ultimatey failed in the carbon-burning auto market.

TimeBased control of the "thermal runaway vicious cycle" could be interesting ... three cells overcharging two ?

[BEMET]

Waterfire, what happens if you short the electrodes while immersed in the electrolyte with the maximum surface area touching each other shorting out?

AntDavison I wonder what it means "thermo runaway viscious cycle"?

All experimentation is fun but any experiment that ends with a loud "boom" is always better.

[btrautman]

I found this absract which I probably will purchase...

Abstract: This research effort investigated the effects of anode depolarization and pulsed DC on the performance of the water electrolytic process for hydrogen generation. An experimental approach was implemented using the Fm01-LC electrolytic cell manufactured by ICI Chemical & Polymers Company. The Fm01-LC had a stainless steel cathode and platinum-coated titanium anode. Using a 10 percent by weight sulfuric acid as an electrolyte, the experimental results show that significant improvement in the performance of the water electrolysis is feasible. The anode depolarization process has the potential of improving the water electrolysis performance up to three times that of the conventional water electrolysis. On the other hand, Using pulsed DC caused current polarity reversal during the off period of the pulse. Placing a diode in the circuit prevented the polarity reversal but allowed the electrolytic cell to maintain a DC voltage level of 2.3 volts. The results of pulsed DC are in conflict with those reported in the literature. A basic research program is proposed to investigate the effects of pulsed DC, anode depolarization with the use of the state-of-the-art 3-D ultramicroelectrodes. jg p.3

[btrautman]

Can someone explain what exactly is pulsed DC. From some reading I found, it is the switching of polarity? Does it stand to reason that the faster or slower you switch the polarity, the higher or lower the frequency given?

If this is so, why use DC for this. Why not use AC that switches polarity.

Also, given the electron flow in a battery, we have a nice organized way of transferring electrons, generating current, etc. When we start switching a polarity at a fast rate, this would seem to upset the chemical reaction. If the purpose of the pulsed DC is to excite the water molecule to enable separation, fine but there seems to be negative side affects to go along with it. Why not use an oscellator attached to the container to physically generate sound waves or vibrations to excite the molecule and use the current to enable the separation process????

Bob

[btrautman]

Continuing with the message above....I see many similarities between a lead acid battery and an electrolysis chamber. In the electrolysis chamber we have water and sulphuric acid as an electrolyte. My understanding of a good electrolyte is one that has many ions. So if we say change the PH level of just water, we would have many ions and it would fit this definition

The electrolyte enables electron exchange with give substrates - say with stainless steel instead of lead. Stainless steel when exposed to air or oxygen forms chromium oxides. Now what can one do with chromium oxides......

Bob

[WaterFireHO]

[AntDavison]

[BEMET]

[btrautman]

[thrival]