Leaking NiMH batteries

On Tue, 9 Feb 2010 01:17:57 -0800 (PST), "
wrote:

I had a few NiMH AA batteries sitting around in storage that hadn't
been used in a couple years. I looked at them just now and a couple
of them were leaking a white crystalline-like substance from the
positive end. Anyone know what this substance is exactly? Is it
toxic and/or corrosive?

Probably a nickel salt. Don't eat it. Chuck the batteries.

BTW, NiMH batteries should never be stored in a discharged state.

wrote:
On Tue, 9 Feb 2010 01:17:57 -0800 (PST), "
wrote:

I had a few NiMH AA batteries sitting around in storage that hadn't
been used in a couple years. I looked at them just now and a couple
of them were leaking a white crystalline-like substance from the
positive end. Anyone know what this substance is exactly? Is it
toxic and/or corrosive?

Probably a nickel salt. Don't eat it. Chuck the batteries.

Nickel salts tend to be green. It is usually a leak of the caustic KOH
electrolyte which reacts with CO2 to form carbonate. Yes it is corrosive
to internal fittings of cameras etc and could give you a caustic skin
burn if handled carelessly.

BTW, NiMH batteries should never be stored in a discharged state.

Unfortunately their self discharge rate is quite high so after a few
months they are in a discharged state even if they started out fully
charged. Lower self discharge NiMH batteries are available too.

http://en.wikipedia.org/wiki/Nickel-...ydride_battery

Regards,
Martin Brown

Bart Bailey wrote:
In posted on Tue, 09 Feb 2010
10:04:22 +0000, Martin Brown wrote: Begin

Lower self discharge NiMH batteries are available too.

I have several from various manufacturers but haven't had any of them long
enough to experience the leakage issue described. They're great to keep in the

The main cause of leakage in rechargable batteries is down to abuse like
over charging and/or overheating leading to raised internal pressure.

P&S that doesn't get used too often so when you hear the screeching tires and
subsequent metallic crunch out in the street you can grab the camera and go get
a few shots without seeing the low-battery indicator.

Sounds a bit scary if that happens more than once in a blue moon.

Regards,
Martin Brown

On Tue, 09 Feb 2010 20:47:10 +1100, wrote:

On Tue, 9 Feb 2010 01:17:57 -0800 (PST), "
wrote:

I had a few NiMH AA batteries sitting around in storage that hadn't
been used in a couple years. I looked at them just now and a couple
of them were leaking a white crystalline-like substance from the
positive end. Anyone know what this substance is exactly? Is it
toxic and/or corrosive?

Probably a nickel salt. Don't eat it. Chuck the batteries.

BTW, NiMH batteries should never be stored in a discharged state.

A little bit of salt on the end of a battery does show it has vented some
contents over time, but this may not detract from its usefulness very much
if it can be charged again after a thorough cleaning. They may have had
nothing more happen to them than being subjected to higher temperatures in
a glove-box for one afternoon cause the venting. Or even an extreme
low-pressure weather situation might have been enough to override the
seal's tolerances to the molecular vapor-pressure of the contents.The seals
working as they should, sealing up again after venting. The fact that they
leaked once is no sign of them leaking again if not subjected to the same
environmental extremes.

Even if it has reversed polarity it can often be nudged into proper
polarity by briefly and intermittently applying a much higher voltage to
the poles, usually 12-15v of low amperage, ~300-500mA, is enough in the
case of reversed NiMHs. They will then continue to accept a full charge for
many years. With difficult to find button-cells that often have this
salt-accumulation happen, I will dissolve the salts under some warm running
water, clean the narrow insulator strip where they accumulated to prevent
further discharge in humid conditions, and still continue using that
battery for many years. My Olympus OM2n depends on difficult to find button
cells. After the last battery-salts cleaning about 8 years ago the metering
system and shutter still work today on the same ones.

My photography has taken me to many remote locations where the closest
you'll come to a battery is an acidic fruit with copper and pyrite nuggets
accidentally stuck in it. I have had to find ways to resurrect whatever I
already had available. I also don't believe in the typical consumerism's
throw-away idiocy.

On 2/9/2010 10:14 AM, Martin Brown wrote:
Bart Bailey wrote:
In posted on Tue, 09
Feb 2010
10:04:22 +0000, Martin Brown wrote: Begin
Lower self discharge NiMH batteries are available too.

I have several from various manufacturers but haven't had any of them
long
enough to experience the leakage issue described. They're great to
keep in the

I have, Eneloops and Kodak. I've had them in camera for over a year and
the camera still operates fine. Sometime after a year I charge them
anyway using an intelligent charger and they fill up in very little
time. Unless you need the added capacity for short time use, these low
discharge NiMH are the way to go.
Hard to judge, but my newer mp3 player with LiOn seems to be better than
my earlier mp3 player using a single AAA

The main cause of leakage in rechargable batteries is down to abuse like
over charging and/or overheating leading to raised internal pressure.

P&S that doesn't get used too often so when you hear the screeching
tires and
subsequent metallic crunch out in the street you can grab the camera
and go get
a few shots without seeing the low-battery indicator.

Sounds a bit scary if that happens more than once in a blue moon.

Regards,
Martin Brown

On 2/9/10 12:41 PM, in article ,
"Better Info" wrote:

On Tue, 09 Feb 2010 20:47:10 +1100, wrote:

On Tue, 9 Feb 2010 01:17:57 -0800 (PST), "
wrote:

I had a few NiMH AA batteries sitting around in storage that hadn't
been used in a couple years. I looked at them just now and a couple
of them were leaking a white crystalline-like substance from the
positive end. Anyone know what this substance is exactly? Is it
toxic and/or corrosive?

Probably a nickel salt. Don't eat it. Chuck the batteries.

BTW, NiMH batteries should never be stored in a discharged state.

A little bit of salt on the end of a battery does show it has vented some
contents over time, but this may not detract from its usefulness very much
if it can be charged again after a thorough cleaning. They may have had
nothing more happen to them than being subjected to higher temperatures in
a glove-box for one afternoon cause the venting. Or even an extreme
low-pressure weather situation might have been enough to override the
seal's tolerances to the molecular vapor-pressure of the contents.The seals
working as they should, sealing up again after venting. The fact that they
leaked once is no sign of them leaking again if not subjected to the same
environmental extremes.

Even if it has reversed polarity it can often be nudged into proper
polarity by briefly and intermittently applying a much higher voltage to
the poles, usually 12-15v of low amperage, ~300-500mA, is enough in the
case of reversed NiMHs. They will then continue to accept a full charge for
many years. With difficult to find button-cells that often have this
salt-accumulation happen, I will dissolve the salts under some warm running
water, clean the narrow insulator strip where they accumulated to prevent
further discharge in humid conditions, and still continue using that
battery for many years. My Olympus OM2n depends on difficult to find button
cells. After the last battery-salts cleaning about 8 years ago the metering
system and shutter still work today on the same ones.

My photography has taken me to many remote locations where the closest
you'll come to a battery is an acidic fruit with copper and pyrite nuggets
accidentally stuck in it. I have had to find ways to resurrect whatever I
already had available. I also don't believe in the typical consumerism's
throw-away idiocy.

And you can probably walk on water...

On 2/9/10 12:41 PM, in article ,
"Better Info" wrote:

On Tue, 09 Feb 2010 20:47:10 +1100, wrote:

On Tue, 9 Feb 2010 01:17:57 -0800 (PST), "
wrote:

I had a few NiMH AA batteries sitting around in storage that hadn't
been used in a couple years. I looked at them just now and a couple
of them were leaking a white crystalline-like substance from the
positive end. Anyone know what this substance is exactly? Is it
toxic and/or corrosive?

Probably a nickel salt. Don't eat it. Chuck the batteries.

BTW, NiMH batteries should never be stored in a discharged state.

A little bit of salt on the end of a battery does show it has vented some
contents over time, but this may not detract from its usefulness very much
if it can be charged again after a thorough cleaning. They may have had
nothing more happen to them than being subjected to higher temperatures in
a glove-box for one afternoon cause the venting. Or even an extreme
low-pressure weather situation might have been enough to override the
seal's tolerances to the molecular vapor-pressure of the contents.The seals
working as they should, sealing up again after venting. The fact that they
leaked once is no sign of them leaking again if not subjected to the same
environmental extremes.

Even if it has reversed polarity it can often be nudged into proper
polarity by briefly and intermittently applying a much higher voltage to
the poles, usually 12-15v of low amperage, ~300-500mA, is enough in the
case of reversed NiMHs. They will then continue to accept a full charge for
many years. With difficult to find button-cells that often have this
salt-accumulation happen, I will dissolve the salts under some warm running
water, clean the narrow insulator strip where they accumulated to prevent
further discharge in humid conditions, and still continue using that
battery for many years. My Olympus OM2n depends on difficult to find button
cells. After the last battery-salts cleaning about 8 years ago the metering
system and shutter still work today on the same ones.

My photography has taken me to many remote locations where the closest
you'll come to a battery is an acidic fruit with copper and pyrite nuggets
accidentally stuck in it. I have had to find ways to resurrect whatever I
already had available. I also don't believe in the typical consumerism's
throw-away idiocy.

In your mind, anyway.

wrote in message
news

BTW, NiMH batteries should never be stored in a discharged state.


What State is politically charged enough for safe storage?


--
Peter

On Thu, 11 Feb 2010 09:23:26 -0500, "Peter" wrote:


BTW, NiMH batteries should never be stored in a discharged state.


What State is politically charged enough for safe storage?

Afghanistan...

In article ,
Martin Brown wrote:

Bart Bailey wrote:
In posted on Tue, 09 Feb
2010
10:04:22 +0000, Martin Brown wrote: Begin

Lower self discharge NiMH batteries are available too.

I have several from various manufacturers but haven't had any of them long
enough to experience the leakage issue described. They're great to keep in
the

The main cause of leakage in rechargable batteries is down to abuse like
over charging and/or overheating leading to raised internal pressure.

Most batteries suffer from electrolyte creeping along the metal.
Alkaline batteries are upside-down, have a large elastic gasket, and an
absorbent pad to hold back the electrolyte for up to 10 years.
Lead-acid batteries have a thick layer of epoxy poured over horizontal
leads that's good for 5 to 15 years. NiMH only last for about 4 years
so they have a smaller seal that saves room for active materials.

NiMH don't have a free-flowing liquid that could spray out from abuse.


P&S that doesn't get used too often so when you hear the screeching tires
and
subsequent metallic crunch out in the street you can grab the camera and go
get
a few shots without seeing the low-battery indicator.

Sounds a bit scary if that happens more than once in a blue moon.

Regards,
Martin Brown
--
I won't see Google Groups replies because I must filter them as spam