Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

Thanks,
Stephen.

Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

Thanks,
Stephen.

The button cells in the car key fobs failed a good while ago. Being a
sensible person I bought two new ones from Maplin for round about 7 quid. No
cheap **** for me!
They only lasted about 12 months. So I shoved in a couple of Pound Shop
batteries which I'd had for ages. You get a card full of different ones for
a quid.
18 months later they are still working fine.

Yes, the technology of the battery makes them suit different uses. Those
expensive ones I find can be used on high drain devices, but of course you
probably then use them up faster, but they are better than the long lived
low current ones. I'd suspect the key fob only needs to operate
momentarily, so the fact the its not a high current cell would not seem to
matter. I'd imagine the high current ones have more plate area and hence
more leakage but higher current capability. Until quite recently you could
see this in rechargeable, but they seem to have managed to make these with
greater life and greater current as well recently.
Brian

"Mr Pounder Esquire" wrote in message
...
Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

Thanks,
Stephen.

The button cells in the car key fobs failed a good while ago. Being a
sensible person I bought two new ones from Maplin for round about 7 quid.
No cheap **** for me!
They only lasted about 12 months. So I shoved in a couple of Pound Shop
batteries which I'd had for ages. You get a card full of different ones
for a quid.
18 months later they are still working fine.


--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!

Chris Hogg wrote:
On Fri, 22 Jan 2016 17:49:27 -0000, "Mr Pounder Esquire"
wrote:

Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot
of the children's toys seem to use them now. Today I found a strip
that I had lost, only it says use by January 2015. I will wait for
something to go flat and try them to see if they still work. Do you
think they will?

Why do batteries have a use by date? Not just these LR44 ones but
any type. Do they self discharge? Is it that even sitting in the
pack, their chemicals are reacting and eventually the reaction
completes, making the battery flat?

Thanks,
Stephen.

The button cells in the car key fobs failed a good while ago. Being a
sensible person I bought two new ones from Maplin for round about 7
quid. No cheap **** for me!
They only lasted about 12 months. So I shoved in a couple of Pound
Shop batteries which I'd had for ages. You get a card full of
different ones for a quid.
18 months later they are still working fine.

I have a similar experience. Bought a card of 50 batteries of assorted
sizes many years ago for £1.90. Still working my way through them.
Whether they still have the life in them that they did when first
purchased, I've no idea, but at just under 4p each, who cares? They
work well enough!

Yup.
I have doubts about Maplin. I tried to do the right thing!

On 22/01/2016 17:09, Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Probably unless you have contaminated them with sweat across the poles.

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

They tend to leak after a while as the stored chemical energy does
gradually get used up by internal self discharge - although it is very
slow in primary cells compared to early NiMH and Lead acid cells.

You will lose some battery life due to ageing but unless they are
obviously leaking then you can still use them.

--
Regards,
Martin Brown

On Friday, 22 January 2016 17:10:48 UTC, Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

Thanks,
Stephen.

IME in 10 years time the majority will still be usable


NT

On Fri, 22 Jan 2016 17:09:32 +0000, Stephen wrote:

Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something to
go flat and try them to see if they still work. Do you think they will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack, their
chemicals are reacting and eventually the reaction completes, making the
battery flat?


The battery chemistry uses the chemical reactions to generate the supply
of electrons (and holes!) in order to generate and sustain an
electromotive force (voltage) whilst supplying current to an electrical
load.

A perfect "battery" (or, strictly speaking, a cell) is one whereby the
consumption of the chemical energy is entirely dependant on the drawing
of current from its terminals. Unfortunately, the perfect cell does not
exist so all suffer from a process referred to as "self discharge", in
essence, unwanted side reactions between the constituent chemicals
responsible for generating the supply of electrons (and holes).

The only cell that comes closest to being 'perfect' in the sense of
eliminating self discharge when in storage is the zinc/air cell but only
whilst its vent holes remain sealed with the protective sealing tape that
keeps the oxidising effect of air from gaining access to the zinc 'fuel'
within.

Once the protective tape is removed, just prior to being installed into
whatever electrical device they are powering (classic use being hearing
aids), they have a fairly high self discharge rate (months as opposed to
years of shelf life with other primary cell chemistries). Normally, this
isn't an issue in most applications where the use of such cells is
mandated.

Next in line for extremely long shelf life are the lithium primary cells
commonly seen in button and coin cell form. These have a shelf life of 10
years when stored at 20 deg C meaning they will only lose 10% of their
initial energy in that time. If you are happy to base shelf life on a 20%
loss, you will get a 20 year shelf life rating.

The ten year shelf life is the industry standard used by the lithium
battery manufacturers to set their BB date but it's useful to keep in
mind that those packs of lithium coin cells in pound shops showing the BB
date as next (or even last) month are still a bargain worth purchasing
since they ought to still have 90% or more of their designed capacity and
won't be losing another 10% of that until you've left them stored for yet
another decade.

The alkaline cell type comes next in terms of shelf life which istr is
something like 5 or 6 years. Without checking, the percentage loss figure
may be a larger value than the 10% quoted for Lithium cells, possibly 20
to 33%. The ordinary carbon zinc cells otoh, almost certainly will be
based on a much larger capacity drop maybe anywhere from 20% to 50% and
on a much shorter time scale, 1 to 3 years? You'll be able to get more
accurate figures from wikipedia (or, indeed, the battery manufacturers'
own data sheets) if you want more specific information than the general
information I've just offered here.

--
Johnny B Good

On Friday, 22 January 2016 20:37:09 UTC, Johnny B Good wrote:
On Fri, 22 Jan 2016 17:09:32 +0000, Stephen wrote:

Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something to
go flat and try them to see if they still work. Do you think they will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack, their
chemicals are reacting and eventually the reaction completes, making the
battery flat?


The battery chemistry uses the chemical reactions to generate the supply
of electrons (and holes!) in order to generate and sustain an
electromotive force (voltage) whilst supplying current to an electrical
load.

A perfect "battery" (or, strictly speaking, a cell) is one whereby the
consumption of the chemical energy is entirely dependant on the drawing
of current from its terminals. Unfortunately, the perfect cell does not
exist so all suffer from a process referred to as "self discharge", in
essence, unwanted side reactions between the constituent chemicals
responsible for generating the supply of electrons (and holes).

The only cell that comes closest to being 'perfect' in the sense of
eliminating self discharge when in storage is the zinc/air cell but only
whilst its vent holes remain sealed with the protective sealing tape that
keeps the oxidising effect of air from gaining access to the zinc 'fuel'
within.

Once the protective tape is removed, just prior to being installed into
whatever electrical device they are powering (classic use being hearing
aids), they have a fairly high self discharge rate (months as opposed to
years of shelf life with other primary cell chemistries). Normally, this
isn't an issue in most applications where the use of such cells is
mandated.

Next in line for extremely long shelf life are the lithium primary cells
commonly seen in button and coin cell form. These have a shelf life of 10
years when stored at 20 deg C meaning they will only lose 10% of their
initial energy in that time. If you are happy to base shelf life on a 20%
loss, you will get a 20 year shelf life rating.

The ten year shelf life is the industry standard used by the lithium
battery manufacturers to set their BB date but it's useful to keep in
mind that those packs of lithium coin cells in pound shops showing the BB
date as next (or even last) month are still a bargain worth purchasing
since they ought to still have 90% or more of their designed capacity and
won't be losing another 10% of that until you've left them stored for yet
another decade.

The alkaline cell type comes next in terms of shelf life which istr is
something like 5 or 6 years. Without checking, the percentage loss figure
may be a larger value than the 10% quoted for Lithium cells, possibly 20
to 33%. The ordinary carbon zinc cells otoh, almost certainly will be
based on a much larger capacity drop maybe anywhere from 20% to 50% and
on a much shorter time scale, 1 to 3 years? You'll be able to get more
accurate figures from wikipedia (or, indeed, the battery manufacturers'
own data sheets) if you want more specific information than the general
information I've just offered here.

I tested a batch of unsealed alkaline cells 8 years past their BB date, and 75% of them were full or almost so. About 25% were of little use. IOW you can greatly exceed the BB dates in practice.

But not too far. My BB 1940 batteries are indeed dead.


NT

On 23/01/2016 21:51, pamela wrote:
On 20:45 22 Jan 2016, wrote:


snip

I tested a batch of unsealed alkaline cells 8 years past their BB
date, and 75% of them were full or almost so. About 25% were of little
use. IOW you can greatly exceed the BB dates in practice.

But not too far. My BB 1940 batteries are indeed dead.


NT

What do you mean by unsealed?

There used to be a series of very rugged NiFe cells that use the same
chemistry as alkaline cells, but were also rechargeable.

https://en.wikipedia.org/wiki/Nickel...93iron_battery

On 24/01/16 12:08, Fredxxx wrote:
On 23/01/2016 21:51, pamela wrote:
On 20:45 22 Jan 2016, wrote:


snip

I tested a batch of unsealed alkaline cells 8 years past their BB
date, and 75% of them were full or almost so. About 25% were of little
use. IOW you can greatly exceed the BB dates in practice.

But not too far. My BB 1940 batteries are indeed dead.


NT

What do you mean by unsealed?

There used to be a series of very rugged NiFe cells that use the same
chemistry as alkaline cells, but were also rechargeable.

https://en.wikipedia.org/wiki/Nickel...93iron_battery

Good batteries. there's also a lithium iron or something..A123?

http://www.hobbyking.co.uk/hobbyking... _Battery.html


--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 24/01/2016 13:03, The Natural Philosopher wrote:

Good batteries. there's also a lithium iron or something..A123?

http://www.hobbyking.co.uk/hobbyking... _Battery.html


Is that Iron or Ion?

Andy

On Sunday, 24 January 2016 12:08:15 UTC, Fredxxx wrote:
On 23/01/2016 21:51, pamela wrote:
On 20:45 22 Jan 2016, wrote:

I tested a batch of unsealed alkaline cells 8 years past their BB
date, and 75% of them were full or almost so. About 25% were of little
use. IOW you can greatly exceed the BB dates in practice.

But not too far. My BB 1940 batteries are indeed dead.

What do you mean by unsealed?

I mean the packet was opened, so no knowing if the 25% dead ones were unused or used. IOW at least 75% were fine 8 years after BB date.


There used to be a series of very rugged NiFe cells that use the same
chemistry as alkaline cells, but were also rechargeable.

https://en.wikipedia.org/wiki/Nickel...93iron_battery

how can a NIFe cell be using the same chemistry as an alkaline zinc & carbon cell?


NT

"pamela" wrote in message ...
But not too far. My BB 1940 batteries are indeed dead.


NT

What do you mean by unsealed?

There used to be a series of very rugged NiFe cells that use the same
chemistry as alkaline cells, but were also rechargeable.

https://en.wikipedia.org/wiki/Nickel...93iron_battery

Tabbypurr was talking about primary cell but that one is a secondary
cell. I'm afraid I can't see how it explains what an unsealed alkaline
battery is.


"pamela" wrote in message ...

On 12:08 24 Jan 2016, Fredxxx wrote:

On 23/01/2016 21:51, pamela wrote:
On 20:45 22 Jan 2016, wrote:


snip

I tested a batch of unsealed alkaline cells 8 years past their BB
date, and 75% of them were full or almost so. About 25% were of little
use. IOW you can greatly exceed the BB dates in practice.

But not too far. My BB 1940 batteries are indeed dead.


NT

What do you mean by unsealed?

There used to be a series of very rugged NiFe cells that use the same
chemistry as alkaline cells, but were also rechargeable.

https://en.wikipedia.org/wiki/Nickel...93iron_battery

Tabbypurr was talking about primary cell but that one is a secondary
cell. I'm afraid I can't see how it explains what an unsealed alkaline
battery is.


Try this:

https://en.wikipedia.org/wiki/Leclanché_cell

Andrew

Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

I've used 9v poundland batteries that were 3 years out of date.
They're still working 9 months later..

Phil L wrote:
Stephen wrote:
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that
I had lost, only it says use by January 2015. I will wait for
something to go flat and try them to see if they still work. Do you
think they will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

I've used 9v poundland batteries that were 3 years out of date.
They're still working 9 months later..

Their 12 for a quid AA 1.5v batteries are utter rubbish.
Not that I've ever bought them of course :-(

"Stephen" wrote in message
...
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they will?

Yes, but not for as long as they will when you use them before the useby
date.

Why do batteries have a use by date?

Because they get worse over time.

Not just these LR44 ones but any type.

That varys with the battery type.

Do they self discharge?

Not usually.

Is it that even sitting in the pack, their chemicals are reacting

Yes.

and eventually the reaction completes,

No.

making the battery flat?

No. More that it isnt as good as it was.

Basically yes, but it depends very much on the type of battery it is. I also
have reason to suspect the electrolyte attacks the seals eventually causing
leakage even if the battery has never been used.
Brian

"Stephen" wrote in message
...
Hello,

I bought a few strips of LR44 button cells because I noticed a lot of
the children's toys seem to use them now. Today I found a strip that I
had lost, only it says use by January 2015. I will wait for something
to go flat and try them to see if they still work. Do you think they
will?

Why do batteries have a use by date? Not just these LR44 ones but any
type. Do they self discharge? Is it that even sitting in the pack,
their chemicals are reacting and eventually the reaction completes,
making the battery flat?

Thanks,
Stephen.

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!

Brian Gaff wrote:
Basically yes, but it depends very much on the type of battery it is.
I also have reason to suspect the electrolyte attacks the seals
eventually causing leakage even if the battery has never been used.
Brian

Used in a Sky remote control, Logitech mouse. The Sky remote control lasted
about 3 weeks before playing up. The mouse about the same before I got the
low battery warning.

"Stephen" wrote in message
...

Why do batteries have a use by date?

In all manufacturing and then retail it helps if possible
to mark items with a production date or code so as to
allow for rotation of stock; everything from tins of beans
to watches and aero engines

As others have said different battery types and makes deteriorate
at different rates if at all. But nevertheless most customers
won't know this, without consulting data sheets etc. and so
can be spooked into binning quite useable items. So that
the production date which is already of benefit to manufacturers
and retailers can be transformed into a marketing tool/gimmick
in many cases by being converted into a use by date.

michael adams

....