Alkaline Battery Leakage

[calzap]

Problem never ends.  I forget to remove alkaline batteries from equipment before storing it and then months or years later try to use it and find it dead with corroded batteries inside.  Most of the time, it's just a tedious clean-up job, but sometimes the device is trashed.  I've also noticed that alkalines are much more likely to leak when left in equipment than when stored outside equipment.

I looked into why alkalines leak, and it's due to hydrogen gas generated inside and pushing out the electrolyte, which is mostly potassium hydroxide.  It's the  KOH that does the damage.  Interestingly, hydrogen gas is not generated in the reactions that produce output current.  Instead it's hydroxide attacking zinc in the battery.  I tried to find the chemical reaction on the net, but best I could find is that it might involve formation of zincate ion.  So the reaction is likely:

     Zn + 2 OH^- + 2 H₂O  = Zn(OH)₄^-2 + H₂

The reaction is analogous to what happens when Al foil is put in lye solution.  The reaction will proceed at all times and will be more rapid in a warmer environment.  But why faster when the battery is in equipment rather than stored?  I hypothesize that when the battery is in equipment, the zinc in the battery acts as a sacrificial anode for minor corrosion that normally occurs on metal parts in a device, including the battery contacts.  Once some hydrogen forces out KOH solution, reactions on the contacts and other metal parts accelerate which makes the internal zinc reaction accelerate too, leading to even more expulsion of electrolyte.

Can the zinc/hydroxide reaction be prevented?  Not really.  If it's an alkaline battery, then by definition, it will have zinc in contact with hydroxide.  There are two traditional solutions proposed: use a hydrogen getter (i.e. absorber or adsorber) or use a vent with a membrane that will allow hydrogen to pass, but not electrolyte.  Both have problems.  Hydrogen getters have  used expensive materials, like palladium, but less expensive ones, like Suisorb, have been developed.  Hydrogen getters may be self-defeating in this application though.  They remove a reaction product (hydrogen) which may accelerate the reaction until the getter is saturated and useless.  Hydrogen-permeable membranes apparently are used with varying success in alkalines.  Problem is the battery can be in various orientations, and if the membrane is below the electrolyte, hydrogen will exert pressure to force electrolyte through the membrane directly or by rupturing it.  Having multiple membranes in different orientations might work, but clogging could still be a problem eventually.

I've never seen a 9 volt alkaline leak.  I'm sure it happens; I just haven't seen it yet.  However, a 9 volt alkaline has six internal 1.5 volt cells surrounded by a secondary container.  I assume leakage does occur from the 1.5 volt cells but rarely penetrates the secondary container.  AA, AAA, C and D cells could be made with a secondary container, but some electrical capacity would have to be sacrificed  to the dead space of the container.

Mike in California

[BradC]

Problem never ends.  I forget to remove alkaline batteries from equipment before storing it and then months or years later try to use it and find it dead with corroded batteries inside.  Most of the time, it's just a tedious clean-up job, but sometimes the device is trashed.  I've also noticed that alkalines are much more likely to leak when left in equipment than when stored outside equipment.

I got so sick of Alkaline batteries leaking I replaced all1.5v  alkaline batteries in the house and all my tools with Sanyo Eneloops and 9v with Powerex low self-discharge 9.6v NiMH. I figure I've paid for the batteries just in not having to repair/replace gear. I have a couple of Maha chargers and I've taught the wife to use them. She has no problem replacing batteries, charging the dead ones up and putting them back in the charged battery jar. We even use them in our clocks (they need charging about once every 18-24 months). I'm about 4 years into my experiment and aside from one set of counterfeit eneloops from E-bay, I'd declare the whole exercise a complete success. I have adapters to put the AA's in C or D applications.
I've removed 10 year old NiMH and 30 year old NiCD batteries from toys just stuffed in boxes that long ago with nary a leak _ever_. I've lost count of the amount of remote controls, meters, toys, or just those tools you use once in a blue moon that I've had to salvage or replace due to alkaline damage.
And I've seen 9V's leak plenty of times. I play in a band and use 9V's in my wireless. Since moving to rechargable for that 6 years ago I'm still on my first set of 4 batteries (keep 'em charged in the guitar case and rotate them) and I've saved over 150 alkalines from the dump (I keep score).

The only place for Alkalines is in a very low discharge application where you can take advantage of the ~10 year life or the 10 year shelf life (5 for 9V). They don't leak until they are past dead. The only Alkalines in my house now are in the Doorbell (4xC cells) and I only just replaced the last set of Duracells and they were 15 years old.

Sorry, you must have touched a nerve.

Nice work on the Chemistry but unfortunately there's no easy solution for Alkalines.

[IanB]

But why faster when the battery is in equipment rather than stored?

I'm not sure this is the case. Alkaline batteries can leak perfectly well when stored in their original packaging. You can even by pre-leaked batteries fresh from the shop sometimes, no extra storage required.

The tendency to leak is increased with "high power" and "longer life" battery formulations. Ordinary formulations without special high power claims are much less likely to leak. Examples of these include Eveready Gold, and various Japanese brands like Sanyo, Sony, Fujicell, Panasonic and so on.

[calzap]

My impressions are subjective; I've not date-tagged a group of new batteries and followed them forward into use or storage.  Most of the batteries we use are Duracell, both ProCell and CopperTop sub-brands,  and Kirkland plus no-name alkalines that come with "batteries included" equipment.  AA and AAA batteries turnover so quickly that storage times are short, so it's not fair to compare leakage in storage versus use.  C and D cells do remain in storage a long while (months to years), and leaks in storage are rare; leaks in use are not.

Mike in California

[macboy]

...
I've removed 10 year old NiMH and 30 year old NiCD batteries from toys just stuffed in boxes that long ago with nary a leak _ever_. I've lost count of the amount of remote controls, meters, toys, or just those tools you use once in a blue moon that I've had to salvage or replace due to alkaline damage....

I recently pulled leaky NiCd cells from a device. There were 1 or 2 leaky cells of 8. They were Pansonic brand (absolutely genuine) and were roughly 20 years old, in storage for the past 15 years in my home. I would happily clean up ten alkaline leaks before wanting to tackle one leaky NiCd. One MSDS I found says" Steps to Be Taken in Case Material is Released or Spilled: Batteries that are leakage [sic] should be handled with rubber gloves. Avoid direct contact with electrolyte. Wear protective clothing and a positive pressure Self-Contained Breathing Apparatus (SCBA)".

I have noticed that Energizer Alkaline packages are claiming "no leaks guaranteed" with the offer to pay to replace your device if they leak within it. My experience with Duracell is quite the opposite. They are almost guaranteed to leak after being depleted.

[calzap]

A few designs ago, I added a circuit to disconnect the batteries when they went down to 0.7V/cell, which extends the amount of time before they will start leaking.  Most devices have no such protection, and if left on accidentally, will drain the batteries to zero, almost guaranteeing leakage of electrolyte.  The circuit I designed also protected against reverse battery polarity, and did so without a diode-drop.  Sorry, I can't post the circuit.

Interesting idea.  Were you able to do some comparison tests?   Did your disconnect mechanism disconnect both positive and negative poles?    How close to the battery did the disconnect occur?

Mike in California

[Fraser]

I have had serious leakage issues with Duracell and their industrial sister Procell. They have leaved within equipment and whilst still in their boxes. It got so common that I stopped using them and moved to Energizer and then to my current favourite cell...... Kodak Alkaline at GBP1 for 6 cells from the Pound Shop (UK). I have yet to have a Kodak Cell leak.

P.S. Gillette own Duracell and Procell (same battery under branding) and they have provided me with several new Maglite's and compensation vouchers after unexplained battery leaks. That makes me think they know they have a leakage problem. They did blame the Maglite end cap spring strength on one occasion and I thought that a possibility but other cells seem to cope.

Aurora

[Yago]

What about sealing the battery compartment(from internal ingress) with silicone?

[IanB]

Kodak Alkaline at GBP1 for 6 cells from the Pound Shop (UK). I have yet to have a Kodak Cell leak.

This is not unexpected. It is reported that the attempts to increase the power output of alkaline cells have the side effect of increasing the probability of leakage. The safest kinds of alkaline cell to use are the ones not burdened by excessive claims of power or capacity, the ones that make use of simple, unboosted formulations. The ones you get in a pound store or dollar store fit this description exactly.

[calzap]

What about sealing the battery compartment(from internal ingress) with silicone?

Yeah, that would be great when it's actually done or is possible.  But manufacturers don't create sealed battery compartments for consumer goods and only occasionally for commercial or industrial gear.  Sealing the compartment yourself works only sometimes because battery compartments are often very open or nonexistent.  Even with a sealed compartment, a leaking battery can make a big mess and ruin the contacts.

I remember having a very expensive micro-balance years ago.  Had a battery (NiCad) on it's main board for keeping the memory with the settings and programming powered.  And yup, it had no containment (actually soldered to the board!), and  it leaked and trashed the board.

Mike in California

[BravoV]

What about sealing the battery compartment(from internal ingress) with silicone?

Still, at some points, not sure about regulation, it still needs "safety vent" which made that sealing pointless. 

[Kjelt]

This is a problem of the last ten years or so, twenty years ago I never had leakage with alkalines unless they were 5+ years unused in a remote control or so. But nowadays I have sometimes leakage within one and a half year. I guess they make them much cheaper then they used to, thinner container material etc.
Worst I had was a brand new RJ45 tester with a 9V Ikea battery (yeah I know  ) two months later I took it and it did not work, opened it up and the whole 9V connector was corroded    Had to replace the connector with a new one.

[BravoV]

These photos were shot at Oct 2013, and they were still fresh tested through "proper" load testing procedure, not just unloaded DMM volt check.

Just watch the printed date at the battery. 

I think this photo is a good reminder that its time to recheck "again" yours if you have any installed in your expensive T&M gears.

[Yago]

Holy sh*t! 2017!!

Cheers for the sealing question.
Mostly concerned for my test gear, cheap as chips but too much for me to replace.

I bought some Duracel for new meters to replace the cheapo ones that come with them.
From the frying pan into the fire eek!

Thought about lithium batteries, but will wait to see if some further light is shed in this thread before I shell out for them.

[Fraser]

@Yago

There was a thread relating to battery capacity testing somewhere on this forum. It os worth taking a look at it. The cheaper alkalines held their own against the more well known standard capacity cells. As I have stated, I recommend the Kodak Xtralife alkalines (not the Zinc Carbon!) cells, They came out well in capacity tests, they are cheap and I have yet to have one leak. The available sizes in GBP 1 packs are:

6 x AAA
6 xAA
2 x C
1 x PP3

There is no D size alkaline stocked at the Poundshop. You could buy some AA or C to D size adapters though

Aurora

[CatalinaWOW]

Old thread, but I had to add my two cents worth, and it is not worth a new thread.  I go through a lot of batteries in various gadgets.  I have observed leaks in unused batteries only once, when stored in extreme conditions (in a car in Arizona) for many years.  In that case all four AA batteries from a major brand were gone.  I can't actually say how many years, but it was probably about 10.  Not less than 7, not more than 14. 

I have near 100 percent leak rate in batteries left in equipment that places a small drain on the battery.   This is totally brand independent.  A Delorme GPS I have is notorious for this.   A few months sitting unused is enough to drain the battery down to the leak creating voltage.