Pumukli
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Electrolysis in series cells?
I was wondering if it was possible to use series connected electrolysis cells with higher voltage?
Reason is I have a beefy lead acid battery charger but it outputs at least 14-15 V when charging the 12V battery.
It can output 40-50 Amperes continuously but I only need say 5-6V to make the desired electrolysis going. The excess voltage just heats the
electrolyte and means energy loss and low efficiency.
What if I connected two (or maybe three) such cells in series? The net current would be the same through all the cells but the voltage would be
divided (more or less evenly).
Do I overlook something obvious? :-)
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Sulaiman
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You certainly can put electrolysis cells in series,
this is precisely what you do when you charge your 12 V battery
which is six cells in series.
for efficiency and plating quality lower current density (A/m2) is better,
and higher than necessary cell voltage is a waste of energy,
which as you noted, turns to heat.
so more cells in series is better up to the point where the combined cell voltages required is more than the power supply voltage.
[Edited on 28-7-2015 by Sulaiman]
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Pumukli
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Arrrgh, the car battery is really six cells in series!
I felt that I may just overlooked something obvious... :-)
Thanks for feeling like a real dumba...s. :-)
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hissingnoise
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| Quote: | What if I connected two (or maybe three) such cells in series? The net current would be the same through all the cells but the voltage would be
divided (more or less evenly).
Do I overlook something obvious? :-) |
Yes you did. That voltage is unaffected by inserting multiple cells but current density is lowered by each extra cell!
If you're electrically minded you could try taking a centre-tap off the output transformer . . . ?
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Fulmen
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Hissingnoise: I think you've gotten it backwards. In a series circuit the current will be the same for all cells.
We're not banging rocks together here. We know how to put a man back together.
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Pumukli
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I think if I used the same geometry for electrodes then the current density would be the same in each cell.
What flows in should flow out in a series of cells (resistors, lamps, etc.)
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j_sum1
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This is exactly what is done in an aluminium smelter. A pot line may be a couple of hundred cells in series. There is about 4 volts drop in each
cell. The whole thing is DC (and un-grounded). Currents are huge.
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hissingnoise
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Fulmen: I think you've misconstrued my meaning . . .
Only an idiot could assume that current density is variable for any circuit!
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hissingnoise
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| Quote: | | This is exactly what is done in an aluminium smelter. |
In chlorate/perchlorate production, too, cells are used in cascade!
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annaandherdad
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The current through each cell is the same but the current density depends on the geometry of each cell. Current is amperes, current density is
amperes per m^2.
Any other SF Bay chemists?
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Fulmen
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Hissingnoise: So it seems, I really don't understand what you're getting at. Why bring up current density at all?
We're not banging rocks together here. We know how to put a man back together.
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aga
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It sounds good !
Why bother with facts when even quantum paticles indulge in Spin ?
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