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I've been thinking about building a new cell with parallell plates instead of 5 neutrals more popular design.
A bit about my background:
I've been actrively testing different types of cell for more than 2 years now and the one currently installed on my vehicle is a OGO ( Taiwan ) 25 plates drycell.. Works very well, no corrosion, water stays clear.
The problem is:
The OGO is only drawing 2 or 3 amps, even if I max out the pwm, or add a rediculous amount of KOH.
It makes about half liter per minute or so, not too bad considering current draw..
I use a PWM wich has a fixed frequency of 16.6 kHz ( Kelly motor controller ) and choke coils in serie with the cell and PWM.
Something is wrong here.. Why I'm I only drawing 2-3 amps? I should be able to draw 60A ( and make 10 litter per minutes ) if I max out the pwm ( 12V )
So my idea is to come up with a drycell with a large surface area, possibly doubling or tripling what I have with the 25 plates, and use a smaller number of neutral plates, OR no neutral at all !
This combined with a smaller plate spacing, of 1 mm, instread of 1/8"
I also thought about using a pump, to circulate the electrolyte, wich will be close to distilled water.. less than 1g of KOH per litter.
To resume the design:
HHO flow cell:
-Pump to circulate electrolyte
-Parallel or few neutral connection
-Small gap, 1mm
-Large surface area: 20 plates 4" x 28"
-Tru slots at each ends of the plates, to facilitate electrolyte circulation
-Springs to keep proper compression on gaskets
as for the drive system, I'd use a similar setup to what I'm currently using, PWM, choke coils, except with a variable freq PWM, that has fast switching mosfets, for fast rise/fall voltage.
I think It's better to keep pulse length at a minimum, to let the cell react with the choke coil.. creating a resonnance effect..
For this you need a cell with a very LOW resistance.. thus the parallel connection..
+ you need low electrolyte, to create a more active gas, and avoid scrubbing out KOH vapors..
+ the lower electrolyte makes the cell more capacitive, instead of just resistive, thus increasing the L\C resonnance effect between the cell and the choke coils.. You don't have to be at peak resonnance to see the benefits of it..
Using tru holes ( aligned holes ) in the plates is usually a big no-no in drycell design, due to current leaks created by the edges of the holes, but in this design, the water is flowing rapidly past the edges, due to water being circulated by the pump, avoiding to normaly occuring current leaks.. ( at least that's my theory ;)
Another possible problem with this design would be corrosion, due to higher voltage between plates.
If it's a parallel connection, it'll be 12V ( or more if it is resonanting ) between the plates..
Normally, this would scream heat, innefficiency and corrosion. But with this design, we're using a PWM and a choke coil combination, with small duty cycle, of 20% or less. This, combined with a large surface area of electrodes will helps reduce the corrosion, cause electric stress is spread over a larger surface.. It is also esier to cool the electrolyte with a radiator if the a pump is used.
That said, your comments and ideas are welcomed.