Why do AAA batteries leak so often?

[lti]

I have seen more AAA batteries leak than any other size of battery. Today, I saw a new, unused Duracell AAA battery leaking inside the factory packaging. What makes them so likely to leak? It seems like the larger cells do not leak as often.

[Th3_uN1Qu3]

They could be fakes. I've never seen a Duracell leak yet, but then again, i tend to use NiMH rechargeables on everything.

[Rulycat]

I've only seen really old stock leak. I find the cheap batteries you get with your TV for the remote never seem to leak. Ever. No matter who makes them.

[tom66]

My dad bought some "2800" mAh cells from eBay, against my advisory instead to buy some good brand 2000 mAh such as eneloops. Anyway, he used them in his emergency torch, but after about a month one of them sort of exploded, it expanded and leaked... something. Half the LEDs on one side of the torch don't light up any more (melted plastic) and the board is bent upwards. These were AA too. I wonder how much capacity these cells actually have? I'm guessing around 1000-1500mAh. If China have figured out 2800mAh cells already, and the biggest you can get retail from say Duracell is 2650mAh, I'm shocked!

[shovenose]

Well, the only brand battery I've ever consistnently seen leek are rayocraps. Other than those, only antes Duracell, fujifilm, energizer, etc.
I think the AAAs are just made cheaper so they leak more often.

[popeye]

You need to by better quality batteries and when they have expired remove then no more leaks simples

[lti]

I don't think they're fake. They were purchased from the local grocery store, just like all of the other batteries I have used. I have seen a lot of Duracell AAA batteries leak with little use. This one had never been used and had a use-by date of 2017. I have some old C and D batteries that are nearly a decade past the use-by date and have not leaked.

[ncovert]

Dunno. I guess since they have a lower current capacity, they just conk out easier

[ben7]

Maybe it is because the can is smaller, and the seal sometimes isn't quite right.

To tell the truth, I don't use Duracells anymore because of them leaking or exploding on me

Especially the Duracell 9v batteries, they bulge out at the end and after a few weeks they explode, even with light use, or just sitting there not being used.

-Ben

[b700029]

The smaller can has a lot to do with it. There is less volume for pressure to build before something gives.

Originally Posted by http://en.wikipedia.org/wiki/Alkaline_Battery

The reason for leaks is that as batteries discharge — either through usage or gradual self-discharge — the chemistry of the cells changes and some hydrogen gas is generated. This out-gassing results in increasing pressure within the battery. Eventually, the excess pressure either ruptures the insulating seals at the end of the battery, or the outer metal canister, or both.

[ratdude747]

Originally Posted by ben7

Especially the Duracell 9v batteries, they bulge out at the end and after a few weeks they explode, even with light use, or just sitting there not being used.

-Ben

That's because Duracell 9V batteries are in reality 6 AAAAs in a can. like AAAs but smaller and thus even more likely to leak. (good to know if you need AAAAs but are cheap).

The same is true for 6v latern batteries... although what kind and quantity varies by brand. some have C cells, some have AAs...

[c_hegge]

I've seen one AA battery leak before. It was some really old no-name brand IIRC. I've never seen a duracel leak, or any other AAA, although I mostly use Energizer Lithium batteries. Lithiums are great because they last for ages and make excellent fireworks when they do eventually die.

[kc8adu]

never seen lantern batts with other than 4 f cells or in some cases 4 d cells.
lots of crap fake video of various batteries full of aa.
eveready used to make a fancy lantern battery in a plastic case that was easy to open.
i repacked some with nimh f cells and reused a charger station that came from odd lots.saved a lot with those.
as for aaa leaking i suspect that in the race for best capacity things like wall thickness of the can and the seal crimp took a back seat .
thick can=less active material.tall crimp area=wasted volume.
this is one way to spot the fake bullshit nimh aa cells.these are made on old low tech equipment and the crimp is huge!.
compare to your eneloops and take note.

Originally Posted by ratdude747

That's because Duracell 9V batteries are in reality 6 AAAAs in a can. like AAAs but smaller and thus even more likely to leak. (good to know if you need AAAAs but are cheap).

The same is true for 6v latern batteries... although what kind and quantity varies by brand. some have C cells, some have AAs...

[Rulycat]

Just had a thought. I've not really seen the failures of Duracells you in the U.S have, and E.U Duracells are made in Belgium whereas yours are made in the U.S.A I think. Some problem at the factory perhaps?

Energizers are still made in the U.S.A here though.

[momaka]

Originally Posted by b700029

The smaller can has a lot to do with it. There is less volume for pressure to build before something gives.

+1

Originally Posted by ben7

Especially the Duracell 9v batteries, they bulge out at the end and after a few weeks they explode, even with light use, or just sitting there not being used.

Well, I've never had one of these explode on me, but the 9V Duracell definitely bulge a lot more than others near their end of life. Energizer 9V batteries on the other hand, do not bulge as much (if at all), but they often corrode their terminals near end of life. Basically I have a box full of batteries that needs to be thrown away and those were my observations from it.

As far as AAA batteries go - yes, those do indeed leak more often than AA and other larger batteries.

[RJARRRPCGP]

The Eveready ones that weigh super light with cat logo, sux!
On a CD player, they die like ni-cads on an RC car!

[lti]

Originally Posted by momaka

Well, I've never had one of these explode on me, but the 9V Duracell definitely bulge a lot more than others near their end of life. Energizer 9V batteries on the other hand, do not bulge as much (if at all), but they often corrode their terminals near end of life. Basically I have a box full of batteries that needs to be thrown away and those were my observations from it.

As far as AAA batteries go - yes, those do indeed leak more often than AA and other larger batteries.

I have seen some 9V Duracell batteries that bulged so much that they were difficult to remove. They were almost 1/4" longer than a new battery.

Maybe I should switch to another brand of AAA batteries. These Duracells leak too often. The one that leaked inside the packaging must have been defective, but I have seen many Duracell (Durasmell?) AAAs leak after almost no use. I don't want the batteries in my calculator to leak.

The picture below shows the batteries I put in the CMoy amp I built about a year and a half ago. I used it for a few minutes, decided that it didn't sound very good, and put it in my junk drawer. Today, two of the batteries are leaking. They were old, but they had been unused until I tried to power the amp with them.

[Agent24]

In my experience, they will all leak eventually when given enough time (years) - The cheaper ones just leak faster.

Never leave batteries of any kind in anything if you're not using it regularly enough to notice when they go flat.

[Shocker]

Is the problem that they need to put vents on batteries??? Like on caps???

[stevo1210]

Originally Posted by Rulycat

Energizers are still made in the U.S.A here though.

That's actually a reason why I buy energizers. I've had Duracells leak as well. A close friend of mine runs a business and got scammed with fake duracells at one point which leaked in the packaging on the shelves, I personally could not tell a difference between the fake and real ones.