Battery terminal corrosion


#1

98 Taurus s/wagon. What would cause chronic corrosion of battery terminals? Battery died and was replaced approx 1 month ago. Positive terminal showed significant corrosion at that time. The new battery exhibiting same (dead battery) symptoms as the old battery, complete with the terminal corrosion.


#2

High resistance in the battery terminal usually a bad connection will cause this.

If it’s badly corroded, replace it.

I service my battery terminals twice a year. disconnect the battery, boil a kettle, let the water cool a little and pour on the battery and terminals. This will clean all corrosion and crud off the terminals.

Follow up with electrical cleaner, use a terminal cleaning brush if you really need to, but sparingly.

Re-assemble and coat with vaseline. This takes all of 15 minutes and is well worth the effort.


#3

There is a seal around the battery posts. Once that seal is broken you’ll have accelerated corrosion for the life of the battery. In this case, the corrosion is from the acid vapors seeping up through the broken post seal.

How do those seals break in the first place? One common way is from excessive lateral force when loosening or tightening the terminal bolts.


#4

Even GM side terminal connections are not forever. It takes a while but with exposure to road salt vapor in the winter, the plating on the ring lugs eventually fails. So, it’s road salt and acid.


#5

I will add one more. Over charging (too high a voltage) can cause it. Oh yea, cheap cables.


#6

Recharging voltage which is too high, above 14.5 volts, will cause the battery to release more acid vapor. Check the charging voltage. If too high, replace the alternator, or voltage regulator if it’s separate.