Battery terminal corrosion prevention

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YY1

YY1

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What are y'all doin?

I've never really had a big issue with it, but my 2015 Renegade failed to start this morning.
Battery checked at 12.67v, which I perceived to be good.
Closer inspection revealed a pretty good amount of light blue corrosion on both terminal clamps.
These are thin brass, plated with something that makes them look like galvanized steel.

Battery is less than 10K miles old.
I swapped the new AGM battery I bought for my 73 into it after cleaning the clamps with a wire brush (difficult to clean due to design) and it started.
I have not tried the Renegade battery yet. It was on a diagnostic charger and only ran about a minute before it was deemed "good" and "fully charged".

I've never really been a big fan of those felt washers, but do they help?
I do have some spray "protectant" but I'm not real keen on overspray getting everywhere.

I don't relish the thought of checking and cleaning the terminals every 5K miles.
AFAIK, the last battery was OEM until it failed at about 75K miles. I never had to clean the terminals before.
 
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Dirty cables causing poor connection and starter/charging issues is a common problem. Regular maintenance should include periodically removing and cleaning post and cable with the proper tool and washing the battery top with clear water. Additional post protection is optional. Felt washers don't do anything, but if you can stand the mess then a protective spray works well.
 
Mask off the battery and spray the the posts and the terminals. It really makes a difference. This is the stuff I have used for the last 10+ years on my newer vehicles that have shown they're prone to corrosion at the terminals.

https://www.autozone.com/miscellane...l_Mjy6IrQ-yKvKHp5MhoC2LcQAvD_BwE&gclsrc=aw.ds

Not all of my vehicles need it. My classics each have a battery disconnect I use each time they are parked. Never corrosion issues on those. I address each as needed.
 
It had occurred to me that there may have been some sort of spray/protectant on the OEM battery connections that was of course, removed when I installed the new battery.
Nothing looked obvious, and I didn't readily notice anything just now when I wire brushed them.

Seems odd, that it would have a corrosion issue in about 8K miles of daily driving.

I've never done anything to any other car I've ever owned.
My Dakota has 140,000 miles by me and 30K previous to me.
It gets driven maybe once or twice a month.
My Satellite gets driven once or twice a week during the spring and fall, but pretty much sits through the rainy season summer and the 2-6 weeks of "winter" we have.
Nothing done to either of those...ever.

I think I will get some type of protectant grease and a small brush.
Again, the design makes application difficult, even of a spray.
I'll do the best I can.
 
I use regular old bearing grease, put a dab on your finger , coat the terminal with a thin layer, then coat the clamp and assemble. Never an issue.
 
I wonder what makes the newer vehicles more prone to this? I have noticed that trend myself. Maybe some of the fellas on here can chime in...
 
Bad Sport said:
I use regular old bearing grease, put a dab on your finger , coat the terminal with a thin layer, then coat the clamp and assemble. Never an issue.
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Old school. Just don't put any between the terminal and cable end. lol
 
PlymCrazy said:
I wonder what makes the newer vehicles more prone to this? I have noticed that trend myself. Maybe some of the fellas on here can chime in...
Click to expand...
I don't think it's necessarily the cables. Corrosion has to have a cause and that's almost always gassing that comes from the battery. When I was still at Oreilly, it was perfectly normal for us to have to keep the battery shelves clean once a week, as there was always acid bubbling out of those cheap pieces of chit.
 
Bad Sport said:
I use regular old bearing grease, put a dab on your finger , coat the terminal with a thin layer, then coat the clamp and assemble. Never an issue.
Click to expand...
This works, as does the preventative spray.
I've been using dielectric grease for the last decade or so, mainly because I have it and use it on other electrical connections.
 
RustyRatRod said:
Old school. Just don't put any between the terminal and cable end. lol
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That reminds me of this. :rofl::rofl:

battery cable meme.jpg
 
RustyRatRod said:
I don't think it's necessarily the cables. Corrosion has to have a cause and that's almost always gassing that comes from the battery. When I was still at Oreilly, it was perfectly normal for us to have to keep the battery shelves clean once a week, as there was always acid bubbling out of those cheap pieces of chit.
Click to expand...
That makes sense.
 
One of the biggest things is to not use bolt on battery cable ends. Those are only meant to be temporary, but everyone leaves them on. WAY too many places for sulfuric acid gasses to get in and attack where the cable contacts the terminal end. Use proper battery cables with made on or professionally crimped on ends and you reduce the chances of corrosion even further. ....and don't buy the cheapest POS battery you can find.
 
RustyRatRod said:
One of the biggest things is to not use bolt on battery cable ends. Those are only meant to be temporary, but everyone leaves them on. WAY too many places for sulfuric acid gasses to get in and attack where the cable contacts the terminal end. Use proper battery cables with made on or professionally crimped on ends and you reduce the chances of corrosion even further. ....and don't buy the cheapest POS battery you can find.
Click to expand...
Never knew that about the "temporary" cable ends. More positive connection. Less vulnerable to being compromised by environment.
 
My Dad, still going at 95 years young, boils the tea kettle and pours boiling water over the terminals. Rinses of the corrosion very fast , then cleans post and terminals (wire brush) Then he would place a real copper penny next to the posts with a dab of grease under them to stay in place. Corrosion would go to the penny 1st. I do all but the penny trick and spray ZEP terminal protector over them after assembly.
 
Whadayaknow-

The battery was bad.

Put it back in and it did the same thing- initially dome light and ODO came on but no start and then several lights flickered, even after key was removed.

Put the AGM back in and it started and drove normally...
Except the door locks don't work.
Not from the button, and they don't auto lock at 30 MPH.
They DO work from the fob.
GREAT!

Battery is a 72 month 4 year guaranteed replacement and is just starting year 3.
Rural King by Exide.
It wasn't cheap.
I've previously sworn by them.

Funny it tested good both with my volt meter and my newfangled charger/maintainer.
I hope I don't get the runaround because it tests good on their tester.
 
I keep a battery tester around. Cheapy from HF but does the job. It’ll simulate the load the starter puts on the battery and give you a little better picture of what’s going on as opposed to just a typical multimeter or battery charger.
 
I use the protectorant impregnated washers, and the spray......this is after cleaning the posts and wire terminals of course. If the corrosion is bad, I use baking soda and water to clean them. For your overspray problem, hold the terminal in your hand with a paper towel behind it to keep the spray from going everywhere. If you can't pull the terminal away far enough to do it, put the spray on a small paint brush and apply it that way.
 
cudamark said:
...If you can't pull the terminal away far enough to do it, put the spray on a small paint brush and apply it that way.
Click to expand...

Or even spray a little in a bottle cap and dip your brush in to apply. Do it someplace you don't mind a little getting on the ground. Or over a garbage can. I've done that with several spray can items before when wanting to apply with a small paint brush.
 
YY1 said:
Whadayaknow-

The battery was bad.

Put it back in and it did the same thing- initially dome light and ODO came on but no start and then several lights flickered, even after key was removed.

Put the AGM back in and it started and drove normally...
Except the door locks don't work.
Not from the button, and they don't auto lock at 30 MPH.
They DO work from the fob.
GREAT!

Battery is a 72 month 4 year guaranteed replacement and is just starting year 3.
Rural King by Exide.
It wasn't cheap.
I've previously sworn by them.

Funny it tested good both with my volt meter and my newfangled charger/maintainer.
I hope I don't get the runaround because it tests good on their tester.
Click to expand...
Glad you got it figured out anyway.
 
Batteries are not rated as how many miles you have driven...They are rated in months.
Unless your car has a properly functioning charging system and is driven regularly, the battery can discharge.
The battery has a + positive side and a - negative side. 12 volt batteries use the negative side as the ground.
The current flows from + to -. The - negative side is the post where corrosion forms.
Lead/acid batteries generate hydrogen/sulphuric gas. This is not only explosive but is highly corrosive.
The purpose of the felt washers ( they are treated with anti-corrosion chemicals) and spray protection is to seal the post/connections from the corrosive gases/vapors given off by the battery.
This is why you should never charge your battery in the car( explosive gases and corrosive vapor can cause damage to other components/finishes)
The electrolyte level should be checked first. If low, use distilled water only as the minerals have been removed and will not contaminate the electrolyte.
Charging a battery is similar to cooking a thick steak. To cook thoroughly, use low heat for a long time. Low and slow.
Use the low setting on your charger and charge overnight if possible. What the charger is doing is causing the sulfate on the internal lead plates to be released giving more surface area for the electrolyte to generate a charge. A 12 volt battery is actually 6- 2 volt cells. 1 dead cell will make your battery a 10 volt battery etc..
When the car is not going to be used for more than a few weeks it is a good idea to at least disconnect the ground cable to prevent parasitic discharge. Especially on newer cars with computers, there is always a slight drain in the electrical system.
It is expensive but as said before, bolt on terminals are designed as just temporary use. Just like a spare is designed for temporary use until the tire is properly repaired or replaced. Use new cables-replace them.
The battery sstate of charge should checked from time to time just like the air prssure in your tires. Don't wait until it fails. Volt meters, and other similar tools are avilable for very little money and should be a part of you tool set.
 
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I believe all modern cars use the negative side as a ground, but, not vehicles are that way. I know many of the older British cars (among others) used the positive side as a ground. Also, keep in mind that on computer controlled cars with various smog sensors, disconnecting the battery resets them to a default mode that takes a certain amount of miles and cycles to get them running in peak performance again. This is important if you have to get the car smogged at a test station. Without proper sensor output to the computer, the test will fail.
 
OK lets just say that since 1956 in the US when most manufacturers converted to a 12 volt system that 99.9% of US vehicles are 12v, - ground.
1955 and before were mostly 6 volt positive ground was common. You can purchase small power supplies that go into the cigar lighter opening to maintain a minimum feed for the ECU.
 
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