Battery connector corroding
 

Please can anyone explain why my Model A battery keeps corroding on the plus connector ?

Re: Battery connector corroding
 

Take it off and wire brush the cable end as well as the terminal, attach, then hit it with some spray paint.

I'd recommend removing the frame ground and doing the same.

Re: Battery connector corroding
 

There are several different kinds of battery post spray/protectant on the market. Might try one. Can't hurt, might help.

Re: Battery connector corroding
 

There are two types of "gook" you can put on it. Using both maximizes your post to clamp contact AND insulates the surface against trickle.

I use Noalox conductive grease on the post/inside of the clamp. This is a product which became popular in the 1980s when many new houses were wired with aluminum wire. Aluminum DOES corrode and the oxidation is thin, but an effective insulator/resistance to current flow. Copper contacts against aluminum yield a "hot-spot" which burned down MANY houses until the wiring manufacturers came up with a conduction solution. The solution was to use an air excluding "conductive grease" of which NoAlox became the primary name among electricians.

On battery terminals, the grease part prevents the thin film of lead oxide from forming and the graphite within the product provides a non-interruptible current path.

Then - when the clamp is in place and snugged up, spray it externally with the yellow spray frequently advertised to eliminate "trickle current" which is the source of the blue/white powder. CRC Battery Terminal Protector is what I have now although CRC sells a gel that can be used, small felt circles infused with the stuff too.

I have been known to wash a battery particularly the top with soap and distilled water (which can come from the dehumidifier) to reduce the trickle.

Doubtless there are other names for battery products to prevent corrosion but you want to separate the conduction issue from the trickle current issue since technically as issues they are at odds with one another - and one product alone is unlikely to solve both.

Joe K

Re: Battery connector corroding
 

When I connect any battery (in a car) I use a little dielectric grease. Never a problem after that.
As to your original question, this site explains it well.
https://mechanicbase.com/electric/ba...nal-corrosion/

Re: Battery connector corroding
 

Use clear water or distilled. You can buy distilled at Target etc. for $1.00 gallon plus you have it for other uses such as servicing the battery. Baking soda with water is a excellent clean up method.

Re: Battery connector corroding
 

Re: Battery connector corroding
 

Possibly The seal between the post and case of the battery is not preventing acid from coming through ---- a guy that used to work with me always beat the terminal on with hammer---- it took a while to figure the excessive terminal corrosion and battery failure some cars were having--- the records showed they were all cars he did something that required terminal removal

Overfilling the cells also can cause acid on top of battery--- only fill fully charged battery, on dead batteries only fill to cover plates till it is charged

Re: Battery connector corroding
 

I also use a little dielectric grease on the ground to the frame.

Re: Battery connector corroding
 

Clean everything up good with a little ammonia. it will neutralize the acid. Make sure your connections are shiny clean and tight. Then put a little of what ever you use, grease, etc.,. on outside to seal it and prevent oxidation.

Re: Battery connector corroding
 

Joe K, you seem to be very knowledgeable about electrolytic activity, corrosion, conductivity & resistivity and I was wondering wouldn't filling the battery cells too high also add to the post corrosion problem?

Re: Battery connector corroding
 

It can also be caused by your generator output being too high. If you are having to add water fairly often, you are boiling the cells dry. That makes the battery emit hydrogen gas and water which will corrode anything nearby.

Re: Battery connector corroding
 

The plus signs are trying to escape the battery without doing any work and are finding the outside world very negative.

Re: Battery connector corroding
 

My car was needing battery post cleaning constantly. My cable from battery to starter was way too small. It had a fat insulator that fooled me. Somewhere you may be getting necked down or restricted by corrosion. Clean up grounds and inspect cables and clamps.

Re: Battery connector corroding
 

lol

Re: Battery connector corroding
 

Corrosion X is fantastic. Used it my boats for years proven in saltwater enviroment.

Re: Battery connector corroding
 

We really need a "like" button. Post of the day.


Joe K

Re: Battery connector corroding
 

After battery post and terminal cleanup I coat it w/silicone grease, works good to prevent corrosion. Been doing it that way for about 50 years or so and so far so good.

Re: Battery connector corroding
 

My father would clean up the battery connections, tighten them down, and ten take a dab of grease from his grease gun and apply it - not sure if that is good, but I do not remember seeing any corrosion on his battery terminals/battery clamps.


Seem to remember in the 60s 70s there were pads you could put down between the cable clamps and the battery posts. Do not know if they worked, or if still available.

Re: Battery connector corroding
 

Anything above the plates is electrolytic inert. No purpose to battery charging, capacity or discharge.

That said, batteries (particularly in the Model A regulated or unregulated) can "hydrolyze" the water in them (over charging causes the water to disassociate and create hydrogen and oxygen which is why battery caps have "breather holes" - to let the pressure out) with a consequent lowering of electrolyte level.

So you either want to carry your level low and check level frequently lest it go below the plates (this is not fatal to a battery but it does cut into its capacity) or keep a modest surplus and check less frequently.

How much surplus is a good question. How often do you check?

As to level being high causing corrosion - corrosion is caused by the electrolyte being "thrown" as a mist by those hydrogen/oxygen bubbles on overcharging. Don't overcharge - no bubbles - or very few anyway.

A greater space above the water line gives the mist some "residence time" to drift back down and recombine with the water level - a "liberation zone" certainly. So to answer the question - keeping the level down SHOULD reduce the mist which escapes from those vent holes. And yes, a high level will tend to move mist outside the battery case causing corrosion.

Many battery vendors now include "recombining" caps with some sort of chemical to grab and re-associate the hydrogen and oxygen and limit discharge to outside. This is a spin-off of the AGM/Gel technology which attempts to limit how much gas/mist a battery creates. These technically should help with corrosion. I think these caps can be bought separately - although I have never used them.

I hope this helps. I'm not a fan of AGM/Gel batteries. Its nice to actually see and appreciate and be able to test with a hydrometer what exactly is going on in your battery - which "Maintenance Free" batteries true to their name are designed to prevent.

Joe K