Things You Will Need
Clean, new grease brush
Plastic picnic knife or similar
Tarn-X Â® or similar
Can of compressed gas dusting air
Step 1To resurrect your non-working device, open your battery compartment and remove the batteries carefully. Dispose of them in the proper manner as required by your local trash laws. Most of the time you will probably see the Potassium Carbonate (CK2O3) residue on both the anode (positive +) and the cathode (negative -) terminals. You do not want to get any of the CK2O3 on your clothes and hands, and especially, your mouth or eyes.
Step 2Note: CK2O3 is actually an alkali. That means it is a Base rather than an Acid. As an example, water (H2O) is about 7.0 on the pH scale, about mid point between the extremes of acidic and basic (See Scale Diagram). From my product testing experience, alkali corrosion is just as detrimental as acidic corrosion.
Step 3The next step is to remove the CK2O3. Get your grease brush and cut the bristles about half way down. It will make it a little stiffer. Stand outside or over a garbage can and carefully brush out the residue. Try not to spread it in areas within the battery compartment. Keep the residue from migrating into the PC board area. That is important. Use a can of compressed air to remove any loose residue. Watch out that the compressed gas does not blow the residue back toward your face.
There will be some hard-encrusted CK2O3 remaining on the terminals. Use the plastic knife to scrape away gently as much as you can without damaging the metal portion of the terminals. Once again, use the air can to remove residue. Continue to scrape the terminals until you are satisfied.
Step 5Note: The reason for using plastic is that you must keep as must metal as possible to maintain the integrity of the terminal. Remove all that you can see. You do not use small screwdrivers, knives (regular or X-Acto Â®), or anything that is metal-to-metal cleaning. To understand the metallurgical aspect of the terminal, you must remember that the contact points (between terminals and battery poles, in this case) are designed for maximum electrical contact with as little resistance as possible. Any degradation to the terminal coating will eventually destroy the connection and will produce failure in the future (just when you really need it). The mating between the terminal and battery ends are called, contact asperities. It is a condition of foreign buildup between the two (2) connection points. The buildup, sometimes microscopic and often caused by the surrounding environment, increases resistance between the contact points. The more resistance, the less conduction, the greater the chance for failure. I taught a seminar on this issue to a class of electrical engineers and technicians.
Step 6To minimize any additional removal of metal coating from the terminal, I recommend using the Tarn-X Â® product. The justification for this is that a jeweler's rouge compound, or an abrasive pencil or ink eraser, can remove and create more damage to the terminal. You can apply the liquid Tarn-X Â® with a cotton swab and coat the entire area of the terminals carefully. Warning, it smells like rotten eggs, and it works well on silver and gold jewelry too. Since it is a mild acid, it neutralizes the alkali and it will stop any further corrosive action on the terminals. The corrosive action of the Tarn-X Â® is minimal compared to all the other types of abrasives.
Step 7Next, get your distilled water and your isopropyl alcohol. Distilled water has no corrosive chemicals in it, so it is a safe liquid. Measure out a ratio of 50% distilled water and 50% isopropyl alcohol. Isobutyl alcohol is better, but not worth the effort to get some and spend the extra cash. You can only get it from a chemical retailer. It is stronger and more effective. The reason for the mixture is that the alcohol makes the water wetter. I will not explain why, just that it will also help evaporate the water much faster.
After the application of the Tarn-X Â® get another cotton swab and use alcohol mixture to remove the Tarn-X Â®.I will assume that you read this before trying the instructional because you want to remove the Tarn-X Â® within a minute of application. Use the paper towels to remove the excess dampness and use extra pressure to remove any remaining CK2O3. Check your work. If you see (use a magnifying glass if you have one) any CK2O3 still remaining, scrape away with the plastic knife again and redo the cleaning procedure for that area again.