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View Full Version : I bought some ZEP



DrBrown
11-13-2008, 10:22 PM
The Lowes stores in my city do not carry the famous Roebic that everyone is using and the best similar product I could find was ZEP crystal drain cleaner. The back contents said it was specifically sodium hydroxide and thats the only ingredient listed. Has anyone else tried this stuff? Its little blue grainy looking stuff. I just built my first cell and I have it breaking in at the moment. I have a battery charging on the 10 amp mode and the battery is taking ~4.4 amps. So at 12v and 4.4 amps the cell was making hardly any bubbles with tap water @ 65 degrees F. I tried adding ~1/4 tbsp naoh and it still didnt do much. Then I slowly added more naoh and finally got more bubbles. Im at ~3/4 tbsp of electrolyte in my pvc container and its getting to the point where its fizzing but the output is very weak. Its been running low power for an hour and is now luke warm. Is the low output due to not enough electrolyte?? Just curious if this brand NaOH is the problem. Any suggestions would be appreciated. Thanks!

Zymosan
11-14-2008, 01:55 AM
I'd get rid of that tap water. Use the distilled water.

DrBrown
11-14-2008, 09:16 AM
What's the difference between distilled and reverse osmosis? We have one of those on the kitchen sink and it would be much easier than buying jugs of water. But I'll buy it if I have to.

I did have a trace of anode mud around the top of the container after an hour or so of runtime. Im assuming thats from the iron in our well water.

IronBear
11-14-2008, 10:12 AM
Reverse osmosis doesnt filter every impurity. It more designed for cleaning water to drink or use for hygiene. It's mostly focused at removing organisms and man made impurities. Most filters dont remove aqueous salts or metal ions which is probably the source of the sludge. It is cleaner than regular water, but can still contain mineral trace.

DrBrown
11-16-2008, 12:40 AM
I did not purchase a jug of distilled agua yet but I did try using all reverse osmosis mixed with 1-1/4 tbsp of NaOH to 1 liter water. The production picked up quite a bit during my test running 12v at 20amps. After an hour the production doubled visibly and was still only ~80* water temps. Im still not sold on this Zep brand stuff but it does appear that the cell will do nicely at 14v. As of now its probably only making 0.5lpm at most when its warmed up. I dont know what the increase will be at 14v versus 12 but with that much electrolyte it should make more. Distilled water should not increase production right?

DaneDHorstead
11-16-2008, 12:37 PM
I did not purchase a jug of distilled agua yet but I did try using all reverse osmosis mixed with 1-1/4 tbsp of NaOH to 1 liter water. The production picked up quite a bit during my test running 12v at 20amps. After an hour the production doubled visibly and was still only ~80* water temps. Im still not sold on this Zep brand stuff but it does appear that the cell will do nicely at 14v. As of now its probably only making 0.5lpm at most when its warmed up. I dont know what the increase will be at 14v versus 12 but with that much electrolyte it should make more. Distilled water should not increase production right?
Doc;

I don't know from ZEP, but I too, deal with a Lowe's store that doesn't carry Roebic.

So, searching online, I found AAAChemical, where both Sodium Hydroxide, and Potassium Hydroxide are readilly available.

Spend a dollar, or so, for a gallon of distilled water, and you will notice a great difference in the quality of the water.

I don't know how many plates you use (wet cell, or dry), or at what gap, or plate design. But I do know that adding just slight increments of increase of the electrolyte, makes very dramatic increases of both heat, and production.

Start with 1 tsp KOH or NaOH, and increase by 1/4 tsp increments, but keep an eye on heat, as well as production.

The more neutral plates you use, dramatic increase is needed in electrolyte ratio.

Early on, I started with 3 gapping (1.1 mm gap) 3 by 4.5" plates +NN-NN+NN-NN+, and used 1 tsp NaOH, and got .79 LPM after burn in.

Changing the configuration to +NNN-NNN+NNN-NNN+ I was able to get 1.89 LPM, but I needed 1.75 tsp of NaOH, and heat became an issue.

Mummy wrapping helped! But still, after running an hour or so, temps reached 170F

Adding additional N plates, to an eventual 5 neutrals between each pole plate, eased heat issues, but caused me to use much, much heavier amounts of electrolyte.

Discussing it on the forumn, I was told to use 28% by weight (which I never quite got to).

I started geting satisfactory results at just over 20% by weight. But, then I use much closer spacing than most. Currently, I produce 2.28 LPM, at an approximate 135 - 138 F - 28 amps

DrBrown
11-16-2008, 02:21 PM
Dane, thanks for the info. That helped a lot!

As of right now here is the cell assembly:
http://www.designbydan.com/pt/cell4.jpg

The cell is wrapped and the spacing is 1/16" apart aside from the center + plate which is ~1/8" apart from the neutrals on both sides. Both - plates on the end are 304 SS and the neutrals are all 302 SS.

My container holds approx 1.5L of water. I have 1-1/4 tbspn of NaOH in the water and it took that much just to get the cell to wake up. Granted its ~60* in the garage so the water starts out but I started at 1/4 tbsp and got nothing but a bubble or two. Im going to attempt at getting a lpm test this afternoon to see where Im at. Thanks again for the info, I will report back with info.

coffeeachiever
11-29-2008, 02:40 PM
Hey Doc,
Why did you space your center positive 1/8 from the other plates instead of 1/16? I think you'll get better results if you cut that gap in half. You should see decent results with just a teaspoon or so of NaOH in that amount of water.

DrBrown
11-29-2008, 04:39 PM
I needed to tighten the strap up against the center(+) plate. All the other neutral plates are spaced by 1/16" nylon washers though. The only option for reducing that space is to find a very skinny nut or try to weld it. But I dont have stainless welding wire and it would corrode faster if I did weld the plate. If you have a suggestion on how to reduce that gap Im listening! :D

coffeeachiever
11-29-2008, 05:44 PM
I do. It's very easy if you have a dremmel, still perfectly doable if to don't. Cut a notch on the top corner of the plate leaving a 1/4" tit. A male wire connector will then slide right on. I posted a link to photobucket showing pics of my dry cell on my thread called "can we get a consensus" in the general discussion area. You can see what I'm talking about there. I had my plates custom cut, but you can do the notch on the wall plates yourself. I am very confident you will get better results if you narrow that gap.

coffeeachiever
11-29-2008, 05:49 PM
I just noticed something else in your picture. I see that you have a - on one end of your cell, a positive in the middle, but not another negative on the other end. If this is the case, nothing on the right side of that positive will produce. You'll need a negative on that open end.

coffeeachiever
12-01-2008, 11:50 PM
Just curious Doc, have you made any progress on your cell?

DrBrown
12-02-2008, 01:22 AM
I can give the details of where Im at now. My electrolyte sucks period. The caustic soda turns to turdy water instantly. Im waiting for my shipment of pure NaOH to arrive. Turns out ZEP only has 40% NaOH, not like its advertised.

When its 55-65*F the production is just a fizz at 12v and 2-5amps. When its warmer there are a handful of big bubbles but a lot more tiny fizzing bubbles. When hooked to a vehicle, still cold, the production didnt pick up much. My can was leaking a bit so output was impossible to measure. I dont know how to reduce the gap between the center plate and the rest. I know that would improve output. I think wrapping the cell definitely reduces the operating temps though, I can attest to that. When my NaOH gets here I will do more testing with distilled agua and report back.

John Sargent
12-02-2008, 07:59 AM
Dane, quick question for you. On your website, you say: "Using four points, to perfectly allign plates (3/4" in from each corner), prevents plates from being warped or bent, especially when Mummy wrapped! This is extremely important, if using any vinyl product, to wrap the electrodes, as vinyl shinks, when heated!"

I have a dry cell that has end plates are manufactured from 1/2" high grade, high temperature Cast Acrylic. No Extruded Acrylic used.

Is it still necessary to wrap the unit? Wrap it in what?

Thanks,
John Sargent

coffeeachiever
12-02-2008, 06:56 PM
Is it still necessary to wrap the unit? Wrap it in what?


Thanks,
John Sargent
It is always good to wrap the cell in an open bath design. Regardless of what your end plates are you will still have current leakage through the electrolyte itself. When I was doing open bath cells, I used bicycle inner tube to wrap mine. It was the idea of another forum member ( I don't remember who to give credit to though). You can get it pretty cheap at Wal-Mart. No matter how well I wrapped the cell though, I always had some current leakage through the electrolyte and eventually thermal runaway. Some people are actively cooling their open bath cells and having a modicum of success with that, but I just moved on to dry cells.

Doc, I don't know if there is a TSC (Tractor Supply Co.) where you are, but they carry the Roebic drain cleaner that is 100% NaOH. If you Google Roebic, they give a good list of retailers that carry their products. TSC also carries a product called Instant Power that is 78% NaOH, 2% KOH and 20% water. It works good for me.
Even if the better electrlyte gives you better results, I would still work on narrowing the gap between your positive and neutrals.
Good luck and keep us updated.