Did I overuse the dielectric grease?

[ironhat]

The contacts on the batteries and the driver of my Ridgid, 18v driver's positive terminals have corroded which won't allow sufficient to operate the drill or for the batteries to charge. I bought a can of CRC terminal cleaner and sprayed liberally but, either my memory if faulty (Quite possible!) or they have changed the formula to one which doesn't work (Also quite possible!). I scraped at the corrosion with a small screwdriver which caused battery #1 to work, but slowly, and began to think there was a better solution. NOTE: I had charged both batteries in the double-bay charger earlier but #2 wouldn't take a charge.
I recalled dielectric grease for connections which had to move as well as conduct current so I bought some and applied liberally to the corroded battery contacts. My reasoning was that my meager attempts to scrape the contacts would be augmented by the conductive grease providing a bridge across the corroded areas. The effect? #1 battery ceased to work. I put #2 into the charger but, when I went to remove it the red light was flashing indicating a battery fault. However, when I removed it from its bay the light continued to flash... even after cycling the power!
I reasoned that the grease had somehow caused a short so I cleaned and scraped battery #1 causing a slow turn of the driver. I reasoned that the grease had soiled the contact in the driver's base so I performed a like cleaning on those contacts. Now, the drill worked! I tried #2 but it had no charge so I returned it to the good bay where it took a charge and now, it powers the driver normally. It looks like I'll be tearing into the other bay for a thorough cleaning.
So, all that to ask this; wherein lay the error in my thinking or application?

[cabinetman]

I just use 0000 steel wool to clean the contacts...no grease.

.

[ironhat]

Remember, I'm dealing with spade and clasp connections buried in the depths of plastic on 5 of 6 sides! That, and the corrosion was really thick on them. Why didn't the contact cleaner cut it - I used several shots which all were saturating to the point that it was running off the tool.

[LCHIEN]

"dielectric" means insulator, not a conductor. Dielectric grease will not and should not conduct anything.

Its use is in high voltage circuits to prevent voltage arcing (like spark plugs) because its voltage breakdown is much higher than air. Because it is waterproof and insulating, many people use it to protect contacts from external corrosion from airborne contaminants like salt air near oceans etc. Usually a thin layer works. Its also a non-rubber degrading lubricant for seals used with electrical connectors. It works with connectors because the spring force of the connectors is usually sufficient to break though the grease and make contact.

If you used a lot you probably used too much..

Spray cans of what they sell as contact cleaner generally is to clean noisy rheostats, dirty switches and dirty signal connectors. It'll remove dust, finger oils, minor oxidation of contacts etc. Its a mild solvent but it will not clean heavy corrosion off of contacts. Sounds like your batteries are leaking electrolyte (commonly happens around the exits from the battery case- e.g. at the terminals) which is usually caustic or acidic and causes the green corrosion on copper contacts and white corrosion on tin plating of copper and steel. If rechargeable batteries are leaking electrolyte they're probably goners.

[unclecritic]

From what i remember about the ridgid dual bay chargers, there is a fuse that is soldered in that will blow if a short occurs, one per bay. I had a 18v battery that i tried on a single charger and it wouldnt take a charge at work. So when i got home i tried the shop dual bay charger, and both bays wouldnt charge. I had another dual bay charger in a box so why not try that one... nope. One battery killed most of my chargers, and at that point realized that every charger i tried would then show a constant error. Apparently im a slow learner. The battery had corrosion from one terminal to another

Trip to radio shack for fuses and some time with a soldering iron and repaired all but one of the bays of a dual charger. Regardless of what i did, whenever a known good battery was placed in it, it would show faulty battery.

Since then all my non lithiums have given up the ghost, so the dual bay chargers are in my graveyard of ridgid cordless tools and batteries

[ironhat]

I'm so embarrassed that I had the purpose of dielectric grease backwards. Thanks for clearing that up, Loring! Along that same vein, what would you use to assure conductivity while preventing corrosion?

Unclectric, I had known about those internal fuses but forgot, of course. Now that both batteries are up and running I'll have to check that fuse when I have more than 30 minutes on the back clock. I pushed it yesterday and had to go to bed at 7:30 and it wasn't very pretty.

Thanks to all. It's always a privilege to participate with this group!

[LCHIEN]

I'm so embarrassed that I had the purpose of dielectric grease backwards. Thanks for clearing that up, Loring! Along that same vein, what would you use to assure conductivity while preventing corrosion?

Unclectric, I had known about those internal fuses but forgot, of course. Now that both batteries are up and running I'll have to check that fuse when I have more than 30 minutes on the back clock. I pushed it yesterday and had to go to bed at 7:30 and it wasn't very pretty.

Thanks to all. It's always a privilege to participate with this group!

conductivity of connectors is assured by adequate spring force contact pressure, smooth and proper plating of the contacts, proper base material, proper plating layers, etc. If it were up to me I would use beryllium copper base spring contacts with 50-100 microinches nickel plating and 20 microinches gold plating over that. With no pinholes. I probably could never design for a company that makes consumer products. A lot depends upon how many conneection cycles you need to withstand.

Chemicals should probably never be needed to enhance connections. Chemicals tend to attract dust and contaminants. Noble (non reacting) highly conductive contacts are the best. Beryllium copper makes the best spring contacts. These will mate reliably with simple pressure contacts. For cheaper tin-plated steel contacts (probably what they use in your drill and battery charger), tin plated steel won't rust but will ordinarily develop a thin tin-oxide coating that's non-conductive. But the force of the spring contacts should be engineered to cut through the oxide when mated with a sliding or wiping action. That will of course reduce the lifetime but a few hundred mating cycles is probably OK for consumer tools.

Factory test fixtures for like iPods and iPhones which are manufactured by the hundreds of thousands need to withstand tens of thousand cycles and still will need to be replaced every couple of years. On the other hand, connectors in your car are probably mated and demated between 1 and 5 times in the life of the car. There's a lot of stuff that goes into connector design.

In my last specification I put a $100 military rated connector in a unit that needs to last for 15-20 years under oilfield conditions. Of course the unit cost was north of $100K. Like I said, I don't do consumer stuff.