What is an electrolyte?

Wikipedia says: "An electrolyte is any substance containing free ions that behaves as an electrically conductive medium".

In human words,(and in the context of hydroxy boosting) an electrolyte makes it easier for electricity to flow through water.

Why do we need this?

Plain distilled water doesn't really allow current to flow through it. It acts very much like an electrical insulator. We add an electrolyte to distilled water so that electricity can flow more easily. Not only that, but an electrolyte can be used to 'control' the amount of current your electrolyzer uses.

Used to "control" current

The Theory (if you hate theory, skip down a little)
Ohm's law states that I=V/R, 'I' is current or amps, 'V' is voltage, and 'R' is resistance. With distilled water, the 'R' in the equation is very large, almost approaching infinity. This means that voltage (a relatively small number) divided by a very large number (infinity) equals such a small number that it is basically zero.

When you add an electrolyte to distilled water, it makes the resistance a little smaller, so now when you take V/R, you get a larger 'I' number. If you add more and more, your 'I' get bigger and bigger.

Real life
You've built a booster, its filled with plain distilled water and plugged in to your power supply but not producing any bubbles. Your multimeter(s) says 13.8 Volts and .1 amps. You want to get your amps up to 5 or so so you add a little electrolyte (lets say NaOH). Your amps jump up to 2. You add a little more - 3... a little more... 5.3 amps. You just made your booster pull 5 amps just by changing how much electrolyte is in your water, Amazing!

Problems with 'controlling' your amperage
The amount of amps your booster pulls isn't just defined by how much electrolyte you add. There are other variables that define the 'R' in the equation above. Some of these are:

• Temperature
• Distance between electrodes
• Electrolyte type

Example: As most boosters run, they increase in temperature. When the temp goes up, so does the amps. So you started out with 5.3 amps but by the end of your test run your at 20 amps. This can sometimes cause a problem.

Common Types of Electrolytes

The two most commonly used and best electrolytes are KOH and NaOH

KOH - Potassium hydroxide
Pros:

• This is known to be the most efficient electrolyte.
• More conductive and soluble than NaOH.

Cons:

• It is caustic. See the safety section.
• Absorbs CO2 from the air, reducing efficiency of electrolyte if left exposed.

NaOH - Sodium hydroxide
Pros:

• A very efficient electrolyte second to KOH
• Less costly than KOH
• Used in conditioning and cleansing a cell
• Easy to find at local hardware stores - Look for 100% lye like the roebic drain cleaner (see image below). Or check the links here
• Somewhat "protects" electrolyzer plates

Cons:

• It is caustic. See the safety section.
• Absorbs CO2 from the air, reducing efficiency of electrolyte if left exposed.

Sodium Bicarbonate - Baking Soda
Pros:

• Not caustic.... at first
• Degrades to sodium carbonate (soda wash) with heat
• Available at every grocery store

Cons:

• Eventually produces a caustic solution - see safety section.
• Gives off carbon dioxide and/or carbon monoxide.
• May harm electrolyzer components
• Useless in efficient/advanced cells, saturation will be reached before attaining desired amp draw