Battery Acid Oh My!

[Chris Strobel]

Well I haven't used my LF gear in well over a year, so yesterday I pulled out the 8x10, set everything up, then pulled out my Minolta F spotmeter, and to my horror the whole spotmeter (even the outside casing of it ) had white crystals all over it.I opened it up and viola! battery acid big time!I spent the next two hours disassembling the thing and carefully managed to get all the acid flakes out and got it all cleaned up.Put a new copper top in it, and to my relief it still works.How on earth did that happen?The AA battery that was in it was a duracell and it could not have been in the meter for more than 2 years.I have flashlights that have had duracells in em almost 6 years and no acid so im a litte perplexed as why this happened, and want to make sure it never happens again.I'm not sure if I had left the meter turned on when I put it away.Could that be the reason?

Chris

[Gene McCluney]

That is why ALL electronics manufacturers recommend removing the battery for long-term storage. I have no idea why batteries do this, but they seem to do this at some point after their useful life has expired.

[Ash]

Think, Rigor Mortis...

[Kirk Keyes]

It's most certainly not acid that came from the battery - it's probably potassium hydroxide that's leaked.

[Chris Strobel]

It's most certainly not acid that came from the battery - it's probably potassium hydroxide that's leaked.

Just found this:

Over time, alkaline batteries are prone to leaking potassium hydroxide, a caustic agent that can cause respiratory, eye and skin irritation. This can be avoided by not attempting to recharge alkaline cells, not mixing different battery types in the same device, replacing all of the batteries at the same time, storing in a dry place, and removing batteries for storage of devices.

Once a leak has formed due to corrosive penetration of the outer steel shell, potassium hydroxide forms a feathery crystalline structure that grows and spreads out from the battery over time, following up metal electrodes to circuit boards where it commences oxidation of copper traces and other components, leading to permanent circuitry damage.

The leaking crystalline growths can also emerge from seams around battery covers to form a furry coating outside the device, that then damages objects in contact with the leaking device such as varnish on wood shelves, and then oxidation and graying of the wood itself.

[Bob Salomon]

Duracell does, or did, warranty their batteries against leakage and damage to the item they were used in if you sent the item with the leaking batteries to them.

Under this warranty they have replaced items like yours when this occurred.

Should you find that they do still do this warranty do not clean the item and contact Duracell for instructions.

My experience was that they were receptive and quick to replace the item or pay me for it.

[GPS]

The white crystals look more dangerous than they are. It doesn't affect most of plastics used around batteries, cleaning the mess itself is usually more dangerous than the white mess. Nickel parts don't suffer too much either, copper yes. Wetting the white parts is better than dry scraping.

[Ginette]

... cleaning the mess itself is usually more dangerous than the white mess.

Can you explain more ?

[GPS]

If you try to dry clean the mess scraping it away you can scratch the plastic, break the wiring... etc. Using the wet method with too much water you can get the liquid to places where you cannot dry it immediately etc. Slow approach usually serves best.

[Joshua Dunn]

Chris,

Did the batteries ever get really hot? Perhaps you left the equipment in a car trunk last summer and hadn’t used the meter since? In extreme heat (130° F) I had some batteries explode in my pocket. I also took some motor drives off some old 35mm equipment that I had not shot with for 10+ years and the batteries had blown in all of them.

Batteries are chemistry; heat and time do strange and unpredictable things to them.