Battery Acid Oh My!

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

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.

Think, Rigor Mortis...

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

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.

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.

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Originally Posted by GPS

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

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Can you explain more ?

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.

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.

Well the way I cleaned it was I separated the two halves of the meter a bit, then just held the half with the battery spring full of crystals under a flow of running water in the sink.The crystals were instantly washed away.I then put some paper towel up in the inards to wick away the tiny amount of water left, blew it out real good with a hurricane blower, reassembled it, and then wiped the exterior real good with some windex wipes.The meter now works fine and looks as good as new.The way the meter was stored was in an air tight ziplock bag which was in my photographers vest, which was stored in a back bedroom in my house.It has sat there unused for probably a little over a year, in heat probably never over 90 degrees, and again the batteries were probably not more than 2 years old.They were duracell alkalyne.I MIGHT have left the meter on before I stored it away.I didn't think of checking this before I started cleaning and testing it.I've had duracells in other gadgets for years and years without ever having this happen.In fact this is the first time I've ever had anything other than my stomach acid up in my 48 years of life.So now I'm spooked and will keep a good watch on this meter.I'm glad I caught it now instead of next month up at yosemite :)

It' strange that batteries leak in our expensive cameras, & equip. but only rarely in a $2 flashlight.
Murphy's gotta have a law about that.

Are you aware that Murphy's an optimist?

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Originally Posted by dsphotog

It' strange that batteries leak in our expensive cameras, & equip. but only rarely in a $2 flashlight.
Murphy's gotta have a law about that.

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Your $2 flashlight is a big cheap plastic switch that fully opens the circuit and prevents the batteries from over-discharging. Your expensive digital camera, in all its glory, pulls the slightest current even when "off" and this will eventually fully deplete the batteries and cause them to want to leak. Sometimes they are successful.

As Kirk mentioned, there is no acid in an ALKALINE battery...

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Originally Posted by Kirk Keyes

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

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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.

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Originally Posted by Joshua Dunn

In extreme heat (130° F) I had some batteries explode in my pocket.

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Also watch out you don't short them out in your pocket with keys or change. I learned that lesson when I was 10 years old with a 9 volt battery!

I allways keep batteries in resealable plasic bags, esp when not using them for any extended time, never had these problems.

Peter