Leakage happens because the negative electrode of the cell is also part of the cell's container structure. As the cell discharges, that electrode is literally eaten away.

From what I've read, and note that I'm not a battery engineer, primary (non-rechargeable) lithium cells don't have this design quirk, so they won't leak when dead. I now use lithium in low-current devices where I might not change the battery for many years.

Remote controls are one example. I put the alkaline cells that come with them in a drawer to use for something else, and drop in AAA or AA lithiums.

So far the only ones I've used have been Energizer brand. They seem to work fine, but the jury's still out on what whether they'll never leak because I haven't been using them long enough for any to go dead.

Another thought, I don't recall ever seeing any leakage from my nickel metal hydride cells. I use those for high current devices such as flashlights. They make way more economic sense for that use anyway.

When I was a geeky lad in the electronic dark ages, cells and batteries leaked pretty regularly. Boy did I ever get in trouble the time I left a 6 volt lantern battery connected to a light bulb on my bed and went out to play!

In the 1960s, "leakproof" was a big advertising deal for carbon-zinc batteries with (IIRC) steel jackets added around the zinc can. They weren't really leakproof, but they were more resistant to leakage. I think that the one that got gunk on my bed (which never washed out) was supposed to be leakproof. So much for that.

Good quality modern alkaline cells are also supposedly leak-resistant. Still, run any carbon-zinc or alkaline battery all the way down, and you're just asking for a mess.

And therein lies a possible problem today. Lots of modern electronic devices don't really shut off. Even when the power switch clicks off like a real one, many times that switch isn't really in series with the battery. It doesn't actually open the circuit. It's just a signal to the gadget's microprocessor to go to sleep.

As that chip dozes, it draws very little power, but it's not zero power. Some drain continues. It can run the battery down over a period of weeks or months, for sure less than its shelf life. Let a mobile phone or laptop computer sit unused for a few months and then try to turn it on again, and you'll see what I mean.

The solution for this everything-has-to-have-an-always-on-computer lunacy is to remove the battery when you're not going to use the device for a week or more.

BTW, the stuff that leaks from alkaline cells is (duh) alkaline, not acidic. That means that the right way to treat device terminals contaminated with leakage is to scrub them with a cotton swab dipped in white vinegar. The acidic vinegar neutralizes the alkaline glop. Try it. It works.

Been using lots of the eneloop rechargeables for over a decade now, have not yet had one leak. They seem to be preferable in almost every way to the throwaways.

The thing I do remember, is that the Duracell's I used 20-25 years ago were made in Belgium and never had that problem. The other note worth mentioning, is that I do not have a problem with any of the D, C, and 9 volt batteries I use in other devices! The problem seems to be confined to the AA & AAA batteries.

And yet, some of us don't have the probem. ???

I also use Eneloop (made by Panasonic IIRC) NiMH rechargeables and they are great. They hold a charge a lot longer than the big box store rechargeables (Energizers suck).

If you're sticking with disposables, if a device is not used for a long time, pull the batteries out. I seem to get leakage when I haven't used the device for a long time.

I am thinking the Panasonic Eneloop's are the way to go. After further searching, I have found that you can get the regular Enloop batteries in the blue packaging. Or the professional in the black packaging. What one's do you guy's use?

Not quite the right description of the failure. The case is not "eaten away" as part of the normal action of the battery. What happens is that the internal seals in the battery fail due to expanding hydrogen gas inside the cell, often exacerbated by heat. Once the guts of the battery (potassium hydroxide) start to leak contact with the air just makes it worse and you get a corrosive mess.

Indeed Lithium batteries don't have that problem. They can leak under different circumstances, but they leak stuff that's not so corrosive. It is highly flammable, however. It can cause pretty serious problems (hence the FAA restricting them in many flight situations; checked luggage, etc..).

The case is not "eaten away" as part of the normal action of the battery.

Thanks for the correction, Ron. My mistake. What I said is true of carbon-zinc cells, but not of alkaline cells. Sorry!

I did not know there were two grades of Eneloop. I haven't bought them for awhile but I'm pretty sure I have bought Blue.

I've never used any of the more expensive Eneloops, just the white cased ones. I've been using them for over 10 years, and haven't had one fail yet, which I can't say for any other brand of rechargeable battery I've used. A few of the really old ones dating back to 2008 have less mah capacity than they did when they were new, maybe down 15% or so, but they still work well enough.

And make sure to remove (rinse off) the acid so it doesn't continue to corrode the battery contacts.