Foreign Substance on Battery

[Mark86]

I was woking with the fuse box under the hood today and noticed something weird on my battery. I hope it is not leaking or corrosion. Here is a picture of what is concerning me:

 

[jharris2]

One quick way to test for corrosion -- put a little baking soda/water solution on there. If it bubbles/foams, then it's corrosion.

Otherwise, you might just wipe it off and see if it returns.

 

[greasefingers]

Mark: that crystalline material is sulfuric acid salt/crystals. All non-sealed batteries vent a small amount of vapor. The water from the vapor evaporates and the solid white particles remain behind. The white particles (H2SO4) are corrosive to metal but only if they get wet again. Just wipe it off with a wet rag, as the acid is completely soluable in water. If it is also found on the sides of the battery, then remove the battery and wash it in the driveway with a gallon of water mixed with a hand full of Baling Soda. Then spray it down with a garden hose. This will neutralize the acid and bring the pH to 7.

Most of time it is nothing. If it reappears within the same week, then the battery may be cracked or the voltage regulator is over-charging the battery.

 

[Mark86]

Thanks for the help everybody. I will definitely keep my eye on it to make sure it doesn't happen again.