Everything You Ever Wanted to Know About Electrolyte
This is a subject I get asked about a lot. People keep asking me for the correct formula for mixing up their electrolyte. “How many cups per gallon?” is a common question. I decided to write a complete summary of information about electrolyte to help people understand the subject. If you still have questions after reading this article, please write to me and ask. I will use your question(s) to make this article more complete. Basics Use steam distilled water only. Look at the label. It must say “Steam Distilled”. Reverse osmosis is not acceptable but is sometimes sold as “Distilled” unless you read the label closely. Distilling is the action of heating the water until it evaporates and then re-condensing the water and collecting it. The minerals in the water are left behind, and only pure water results. Minerals in the water will leave a white coating on your plates that will eventually cut down on HHO production. If it gets bad enough, the cell will stop working completely. So this point can’t be underestimated. Use Potassium Hydroxide (KOH) or Sodium Hydroxide (NaOH). Don’t mess around with all the other electrolytes you hear about out there. These just don’t work well, need constant replenishment, and some of them even create toxic gasses. We prefer KOH because it has better antifreeze properties than NaOH. So if you are in a cold climate, there is no real
choice. In warm climates that never get much below freezing you can use NaOH if you prefer.
Whichever you use, be sure to get pure chemical. You don’t need lab grade, which is expensive. But don’t get a mix with other chemicals such as can be found in some drain cleaners. The other chemicals can ruin your stainless steel plates. Drain cleaners are OK but they must say “Pure Sodium Hydroxide”. The common name for KOH is caustic potash. The common names for NaOH are caustic soda or lye. So pure lye, for example, would be pure NaOH and would be OK to buy.
If you live in a small town like I do, then you may have to order your electrolyte from an online supplier. If you live in the United States, you can use the same supplier I do. I use DudaDiesel.com for my KOH, both bulk and for small quantities. For those that live outside the U.S., you’ll need to find a supplier in your own country. Shipping these chemicals internationally has so much red tape that I’m not aware of any companies that will do it. So use google and limit the search to your own country. The types of companies that will have it are biodiesel products suppliers, soap making products suppliers, and chemical suppliers.
When you use KOH or NaOH, you don’t need to add more electrolyte when you refill your reservoir. Just add more steam distilled water. The only time you’ll need to add electrolyte again, is if you flush and refill the system. Note, if you find you need to replenish electrolyte, then you must find out how the electrolyte is getting out of your system. If you can’t find an obvious leak, then it’s probably being forced into your engine due to an incorrect installation. This is bad and must be solved immediately so you don’t ruin your engine. But under normal operation the electrolyte doesn’t need to be replenished.
Aside from electrolyte, the only thing you should add to your distilled water is a pool and spa de-foaming agent. The active ingredient in these is polydimethylsiloxane. It always comes in a liquid form with the active ingredient emulsified in water and looks like a thick milky white liquid. We
include some of this now in all of our kits. Add a 1/2 – 1 teaspoon per quart. It doesn’t bother HHO production at all. If you see foam in your reservoir, be sure to add more until there is no foam anymore. Like electrolyte, you only need to add it once, as it will stay in the reservoir after as the water is used up making HHO. We get ours from the local hardware store and it’s just called “Pool and SPA Defoamer”. I’m sure specialty pool supply stores would also have it.
Anti-freeze agents: Don’t use them. We have tested every form of alcohol in testing to see if we can lower the freezing temperature of the electrolyte. They all cause HHO production to fall dramatically. Despite anything you read anywhere else, don’t do it. You can end up ruining your cell as it will get coated with gunk and require complete disassemble and a rebuild to correct. KOH is the best antifreeze agent to use. Just add more for cold climates. You may end up with too strong a mix, and this may cause a small reduction in efficiency, but it will work. Other antifreeze agents won’t. For more information about this, including a chart showing KOH concentration vs freezing temperatures, see KOH Freezing Temperatures
Electrolyte and Current
More electrolyte = more current = more HHO. This is actually only true up to a certain logical maximum concentration. After that point the solution will get saturated with electrolyte, and any more added electrolyte will not dissolve in the water, and therefore will not increase the conductivity of the water. But within reason, more electrolyte = more current = more HHO. Therefore we must add enough electrolyte to get the amount of current we want.
Here are the main factors that affect current:
Electrolyte concentration: We’ve just covered this. More electrolyte = more current. But realize that as you use up the water in your reservoir, the electrolyte stays behind. Therefore the remaining water in the reservoir is getting more and more concentrated because there is less water, but the same electrolyte. The electrolyte concentration increases dramatically when the reservoir is nearly empty.
Temperature: If the cell is warm, it conducts more current. If it is cold, it conducts less. In the winter, you may need to add more electrolyte. This is also the cause of “thermal runaway”. This is something that happens with systems that don’t have a self adjusting, constant current PWM. What happens is that as the cell starts producing HHO, it warms up. This causes it to draw more