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richardb200373
08-31-2008, 03:49 PM
Hi guys, I've been reading alot of the posts to try to find some answers to my problem but still not sure, any help would be appreciated.
I built a unit with design from gas4free. I am using 11 plates, 6 neg and 5 pos. Plate size is 2.25"x3.75". I cut the 316 24ga. plate with tin snips. Needless to say, they are'nt perfectly straight, some are deffinitly bigger than the others, but not too much. Had to shave some off so I would'nt hit the plate with washers too. Are plates not the same size a problem?

The unit holding the plates is made of 1/2 polycarbonate (plexyglass). The size is very small, 6x5x3" , a bubbler is on one side seperated from plates, so all the water it can hold is about .3 liters, not too much. Is this too small, water getting too hot too quick?

I mixed 1/4 teaspoon baking soda with 1 liter of water. Not blowing 30A fuse blow 20A after a minute or so, but wires are getting hot. I am going to switch wires to 12 ga.
I am testing this directly to the car battery with fuse, should'nt matter if I'm not testing with the relay in place right?

Also, I was told to use 20ga. stainless wire for plates to terminal, I've got some that is solid wire, not strand wire, is this ok? Currently have 12 ga. copper wire for test, insulation stripped of course.

My hho output from these tests have only been about half a liter per minute, just in quick startup tests... Not what I was expecting, wanted at least 1LPM. Sorry for being so long winded, anything will help, thanks in advance.

djerickd
08-31-2008, 04:22 PM
I'm thinking maybe wrap the cell and get KOH for your electrolyte

ridelong
08-31-2008, 04:55 PM
richardb200373,

With a cell that small, I would recommend running it around 2 amps. The amount of electrolyte somewhat determines how much current you can run, due to electrolyte heating. As the electrolyte heats, it causes higher current.

I run a 1/2 gallon gen., and I won't run it over 10 amps to protect it from boiling.

One thing you can do is add neutral plates. I run +nnnn-nnnn+ in my generator and it seems to help with the heat. If you need info on neutral plates, search it on this site.

Also, I recommend distilled water. You start with a known substance. Tap water is an unknown.

The chemical for electrolyte is potassium hydroxide, it dosen't gunk up the cells. I haven't changed electrolyte in my truck for over a month, just add distilled to keep level at same place. Just be carefull, the stuff is caustic and will burn skin. Keep vinegar around to neutralize any spills.

The best way to determine how much electrolyte is to add small amounts and check current. Adding until you have the current you want, minus a little to allow for heating. Harbor freight sells a cheap $5 meter with a 10 amp scale.

One last thing, Please don't light the output line of your generator. I've seen too many people blow up their gens.

Hope that helps, good luck.

EltonBrandd
09-02-2008, 12:33 AM
If your plates are uneven you will have massive current leakage. Also I can imagine how wavy the plates are too. If the gaps aren't consistent then your very likely to have large current flowing through the smallest gap due to it being the easiest way back to ground. Straighten out your plates and wrap them with shrink wrap. You should be able to run at about 8amps cold and top out at 16amps hot.

Westcoastrocks
09-02-2008, 01:15 AM
I'm thinking maybe wrap the cell and get KOH for your electrolyte

I agree do this first then see what happens.