Low amp 12V open bath 9 plate series cell plan

[sucahyo]

Hello,

I currently planning to build my first HOD generator. I want to install it to 100cc engine. I want it to be low ampere to avoid draining the battery. Please comment wether my plan bellow is viable or not.

Here is my plan

Step 1. deciding electrolite mix
I think that to reduce ampere it is better to use electrolite with less conductivity. Based from:

V = I * R

I am thinking to increase resistance to reduce drawn current.

To get more resistance, the concentration of NaOH need to be low. Maybe with 1% NaOH solution.


Step 2. deciding voltage
Based from references, voltage between 1.24 and 1.48 is best because it will make endotermic reaction which absorb heat from environtment. Since I decide to use series cell type, the closest configuration for this would be 9 plate series cell. Using 12V input isolated 9 plate series cell would have potential of 1.33 volts in each plate.


Step 3. deciding electrode area size
Based from my previous experiment using ground water and 1.5 volts battery, hydrogen gas can only be released on very small electrode surface, around fingernail size. This small surface would make implementing isolated series/tubular cell impractical.

I plan to decide area size needed by submerging 1.5 volts charged base plate little by little in electrolite. I will cut it at the submerge height at the time the base plate start releasing no bubble / very small bubble instead of initially big bubble.


Step 4. deciding electrode gap
Based from references. Problem with open bath series is uneven voltage accross plate. I am thinking to reduce this effect by making the resistance between all plate equal. By making equal resistace accross the plate, I hope I can get equal voltage.

I plan to variate the distance between each plate to make it have same resistance. Maybe by making the inner plate have wider distance than the outer part. I plan to fully submerge all plate into the electrolite (water level just over the plate top) and start moving around the plate until I get the same resistance for all plate.



I plan to use half wave rectifier (one diode) DC converted from onboard AC generator, in raw dc mode, without any other electronic. The output will be feed before air filter.


If hydrogen generated is too small, I plan to use higher concentration NaOH to get more of it.


Do you think this plan is viable? Do you have other suggestion?

[Rocko]

sounds like a plan

     My experience, I built a small 9 plate cell to its optimum performance with just tap water and then switched to distilled water with just a pinch of NaOh and it produces rather well with just 12v . no exact figure on amps yet but they are important. I do know I'm not useing anywhere near 20amps as i hook it to a battery the spark is little and the cell gets warm not hot.
   
     Ive been using it for a couple months and its worked well but I just got it working really good after some small changes and dont have exact figures yet do to lack of free time. My next step is to build it bigger and use an inverter like you mention but with components to smooth the current  and keep the DC  pulsed.

     I have found that 316 stainless steel works well but hear titanium is better,  do not use copper, brass or any other corrosive material in the cell or the results could be dangerous. be sure to use a flashback arestor or a water bubbler between engine and cell.

Not sure if any of that helps but its my 2 cents....... good luck

[sucahyo]

Thanks .

316 SS is rare in here, so I have to use 304 maybe even 302.

How big is your plate? How wide is the gap?

[sucahyo]

I do another experiment yesterday. Trying to find correct gap between plate. But since I calculate it wrong I end up cutting my 20cm ruler (my test plate) to 8 pieces (around 0.5 square inch each). Using ground water and two 9 volts batteries in series (18 volts).

My final arrangement look like picture bellow:


Plate gap in milimeter: 2-4-6-6-6-4-2
The voltage between plate is between 1.9 to 2.2 volts. But it change when electrolyte concentration change. When electrolyte concentration is too high only the first negatively charged plate released bubble. Using this configuration the voltage distribution is good but only the first and second plate produce bubble.


I experiment other configuration too. This one bellow have unique characteristic:


Plate gap in milimeter: 2-4-6-8
This weird layout still make the first negative plate released most bubble, but somehow the 2nd, 3rd and 4th plate release bubble at the same rate, about half the rate of the first plate. But this behaviour will change when using electrolyte with higher concentration, the neutral plate will have reduced bubble, and the first one will have more bubble.

No gas release at the positive plate so far.


I notice that bubble release easier when plate submerged deep into water. I guess this is the benefit of open bath type. It also release easier although at less rate when there is "obstacle" layer on plate.

[sucahyo]

After more experiment I plan to make much smaller surface now. It seems 0.5 square inch is still too big to be able to release gas at lower voltage.

I still in the begining of reading "High voltage HHO by IronHead", many good tips, I think that thread should be stickied.


But I still don't understand why anyone use large (more than 1square inch)  surface plate. Maybe they after big ampere?

I read somewhere that gas will generate faster on higher volts per square inch. Why is everyone increasing volts instead of decreasing surface area?

Many people mention that gas production is higher using the same surface area size when voltage is increased.

But do anyone ever experiment wether the gas will be increased or reduced if we reduce the surface area on same voltage?

I wonder if many conditioning method pruposes is to make insulation layer so the area involve in electrolysis is smaller? Maybe we can paint them or apply glue to them if this is the case.


What I currently think:
- large surface reduce resistance, thus increase ampere, also have less volts per square inch.

- close plate reduce resistance, thus increase ampere

- higher electrolyte concentration reduce resistance, thus increase ampere


What I want is gas generation at highest resistance possible, low ampere, using voltage differential as low as possible.

I still try to find the easy to achieve combination of low ampere and low voltage. Do I have to use needle sized surface ?