My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so you
must take care when fitting a new battery not to "short the terminals with
your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body resistance
of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me to
do?

On 03/10/2020 11:56, NY wrote:
My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me
to do?

'Short' is a binary term for something that in this case is far from binary.

typical resistance between fingers will be in he several hundred kilohm
range. Not enough to upset a low voltage battery.

Two wet fingers across my multimeter got me about 180k
Note that 30mA is RCD trip current for safety, so that implies a human
body might be somewhere on the 50mA at 240v = 4.8K region worst case
with two hands wrapped around conductors...

I managed to pickup a live lamp-holder I was working on the other month
and got a nice 'trembler' Didn't trip the RCD...



--
"First, find out who are the people you can not criticise. They are your
oppressors."
- George Orwell

On 03/10/2020 11:56, NY wrote:
My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

Bridging the insulation between the positive and negative terminals with
a sweaty fingerprint will shorten the battery life somewhat. But it
would have to be a very low capacity battery for holding onto the
terminals for a few seconds. Very few people are lower than 50k skin
resistance and some are as high as 10M.

Biggest danger from them is children swallowing them which can cause
very serous internal electrolytic burns.

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me
to do?

There is truth in the don't put a fingerprint across the insulation that
separates the two terminals. Much like don't put fingerprints onto
quartz halogen bulbs - the sodium chloride and skin oils cause trouble.

--
Regards,
Martin Brown

"NY" wrote in :

My wife has always believed that if you touch both (and maybe just
one) terminal of a flat disc "button" battery (eg CR2032, CR1620 as
used in a watch, key fob, PC BIOS), you will cause the battery to
discharge, so you must take care when fitting a new battery not to
"short the terminals with your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises
me to do?


I have always follwed that advice.

On 03/10/2020 11:56, NY wrote:
My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me
to do?
bollox...but you need to keep them clean ....

No not really. Some small button cells have a tiny hole with a sticker over
it which activates it and then its age is limited. I think the ingress of
air is needed, but I'm no chemist. The main problem with those batteries is
contamination from your fingers. You should but I seldom do, handle them
using cotton gloves to stop the grease getting on them. Because the current
drain from them is small, any kind of build up of resistance can make them
crackle as the terminals oxidise or the muck gets in.
Brian

--
Brian Gaff -

Blind user, so no pictures please!

This document should only be read by those persons for whom Paranoia is
normal
and its contents are probably boring and confusing. If you receive this
e-Mail
message in error, do not notify the sender immediately, instead, print it
out and make
paper animals out of it. As the rest of this disclaimer is totally
incomprehensible, we have not bothered to attach it.
"NY" wrote in message
...
My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so you
must take care when fitting a new battery not to "short the terminals with
your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me
to do?

On 03/10/2020 11:56, NY wrote:

My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

I think this is one of those old wives tales that started with a grain
of truth, but then the actual detail got lost along the way, and now the
"fact" recalled is nothing to do with the actual issue[1]

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Indeed. Things like button cells can be used in applications where they
will last years, so making sure there is no contamination of the
surfaces makes sense. However you will not drain any noticeable energy
though your fingers while poking it into its socket.

Is there any truth in what she's always believed and what she advises me
to do?

[1] Bit like when people try to tell you that turning on a fluorescent
light will use 15 mins worth of electricity. The real deal is that
starting a lamp will use up some of the life on the heater coils, and
eventually could cause a lamp to fail to start - thus raising the
overall costs per hour..- but drawing 15 mins of energy in the couple of
seconds required to start it, is something the circuit breaker might
have a thing or two to say about!

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Saturday, 3 October 2020 14:56:00 UTC+1, John Rumm wrote:
On 03/10/2020 11:56, NY wrote:

My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

I think this is one of those old wives tales that started with a grain
of truth, but then the actual detail got lost along the way, and now the
"fact" recalled is nothing to do with the actual issue[1]

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Indeed. Things like button cells can be used in applications where they
will last years, so making sure there is no contamination of the
surfaces makes sense. However you will not drain any noticeable energy
though your fingers while poking it into its socket.

Is there any truth in what she's always believed and what she advises me
to do?

[1] Bit like when people try to tell you that turning on a fluorescent
light will use 15 mins worth of electricity. The real deal is that
starting a lamp will use up some of the life on the heater coils, and
eventually could cause a lamp to fail to start - thus raising the
overall costs per hour..- but drawing 15 mins of energy in the couple of
seconds required to start it, is something the circuit breaker might
have a thing or two to say about!

I once did a calcualtion on that & concluded that the total costs of leaving a linear fluorescent light on were only beneficial for a matter of seconds, beyond that it was cheaper to switch off. A molehill had been made into a mountain somewhere.


NT

NY formulated on Saturday :
I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body resistance
of many kilohms will cause the battery to go flat.

It's the sweaty/oily deposits from your skin which is a problem, it can
short across the insulator and cause the low power cells to discharge
and reduce their working life. You should only touch them with
insulated tweezers, to avoid this.

On 03/10/2020 17:02, Harry Bloomfield wrote:
NY formulated on Saturday :
I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

It's the sweaty/oily deposits from your skin which is a problem, it can
short across the insulator and cause the low power cells to discharge
and reduce their working life. You should only touch them with insulated
tweezers, to avoid this.
Utter ********


--
There is nothing a fleet of dispatchable nuclear power plants cannot do
that cannot be done worse and more expensively and with higher carbon
emissions and more adverse environmental impact by adding intermittent
renewable energy.

The Natural Philosopher has brought this to us :
Utter ********

Your skin deposits are conductive. Were that no so, you would be unable
to receive a shock when touching mains voltages, nor would you leave
fingerprints behind, on everything you touch.

On Saturday, 3 October 2020 17:43:59 UTC+1, wrote:
The Natural Philosopher has brought this to us :

Utter ********

Your skin deposits are conductive. Were that no so, you would be unable
to receive a shock when touching mains voltages, nor would you leave
fingerprints behind, on everything you touch.

Semi-true. As an argument for not touching batteries it's a nonstarter.

On 03/10/2020 17:43, Harry Bloomfield wrote:
The Natural Philosopher has brought this to us :
Utter ********

Your skin deposits are conductive. Were that no so, you would be unable
to receive a shock when touching mains voltages, nor would you leave
fingerprints behind, on everything you touch.

but they are only conductive when wet, and fingerprints are oils, not
water based solids

And the water based parts dry out.


--
There is nothing a fleet of dispatchable nuclear power plants cannot do
that cannot be done worse and more expensively and with higher carbon
emissions and more adverse environmental impact by adding intermittent
renewable energy.

NY wrote:
My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so
you must take care when fitting a new battery not to "short the
terminals with your fingers".

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Is there any truth in what she's always believed and what she advises me
to do?

The cell consists of two corrosion-resistant surfaces,
and an air gap. Below the air gap is some dielectric
material which does not conduct.

To discharge the battery requires shoving a significant amount
of material into the insulating gap.

The only reason for keeping finger oils off battery contacts,
is in the belief it will lead to unreliable contact with the
terminals. The socket materials are not as good/expensive
as the cell materials.

While you might drop the cell several times while
handling it, it's not likely to have a "deep discharge"
event.

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Paul

Paul wrote:

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

All the button cells I have bought in the last few years have 'use
before' dates on them (or something like that).

--
Chris Green
·

In message , Paul
writes
Snip

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Some battery powered devices have a constant battery drain despite being
*switched off*.

My two are a pistol grip laser thermometer and a digital vernier gauge.
Left connected, 4 weeks battery life:-(

--
Tim Lamb

On Sat, 3 Oct 2020 20:50:52 +0100, Tim Lamb wrote:

In message , Paul
writes
Snip

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Some battery powered devices have a constant battery drain despite being
*switched off*.

My two are a pistol grip laser thermometer and a digital vernier gauge.
Left connected, 4 weeks battery life:-(

Verniers are bad for that. I have an Aldidl one that takes a an LR4 and
would last a few months at most. Although I didn't 'need' it I got another
one from Aldidl that takes a CR2032, thinking that the bigger cell should
last a lot longer; it doesn't!

BTW, I've a vernier caliper that doesn't take a cell but I can no longer
read it very well. If someone wants it, drop me an e-mail - free to a good
home where it'll be used.
--
Peter.
The gods will stay away
whilst religions hold sway

Of course there is always waste, both in the form of heat and sound from
those lights, depending on the way they are started and if it has a
gynormous choke or not. Many of the so called low energy fittings and lamps
tend to spew out RF which is basically wasted. Hum from the choke, and
heat in the starter bulbs loses energy.

I guess you could design some very kind starters for them, indeed the old
battery ones suggest to not even use the heaters, at least not on the one I
had it just developed a very height voltage till it started, then lowered it
to the most efficient running voltage when conduction was in progress.
They still got tired though and would enter that flash on and off behaviour,
first noticeable in the cold. I'd imagine the particles inside did something
to the electrodes and or the phosphor on the inside of the tube after some
time.
Brian
--
--
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"John Rumm" wrote in message
...
On 03/10/2020 11:56, NY wrote:

My wife has always believed that if you touch both (and maybe just one)
terminal of a flat disc "button" battery (eg CR2032, CR1620 as used in a
watch, key fob, PC BIOS), you will cause the battery to discharge, so you
must take care when fitting a new battery not to "short the terminals
with your fingers".

I think this is one of those old wives tales that started with a grain of
truth, but then the actual detail got lost along the way, and now the
"fact" recalled is nothing to do with the actual issue[1]

I can imagine that sweat on the metal terminals *may* cause a bit of
oxidation over a long period of time, but I can't see how a body
resistance of many kilohms will cause the battery to go flat.

Indeed. Things like button cells can be used in applications where they
will last years, so making sure there is no contamination of the surfaces
makes sense. However you will not drain any noticeable energy though your
fingers while poking it into its socket.

Is there any truth in what she's always believed and what she advises me
to do?

[1] Bit like when people try to tell you that turning on a fluorescent
light will use 15 mins worth of electricity. The real deal is that
starting a lamp will use up some of the life on the heater coils, and
eventually could cause a lamp to fail to start - thus raising the overall
costs per hour..- but drawing 15 mins of energy in the couple of seconds
required to start it, is something the circuit breaker might have a thing
or two to say about!

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Yes, I've had the old black pea in a pack. I did send it back and got a free
new pack. No mention of fake. This was the old Energiser brand, used to be
Ever Ready I'd imagine, which when you think of it was a lie in the name, as
in the old days, even when they rebranded to Berec was not true. Most
Japanese batteries of the same era outperformed them. Duracell outperform
Energisers as well, indeed Sainsbury's own brand out perform energisers!
Brian

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

Blind user, so no pictures please
Note this Signature is meaningless.!
"Tim Lamb" wrote in message
...
In message , Paul
writes
Snip

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Some battery powered devices have a constant battery drain despite being
*switched off*.

My two are a pistol grip laser thermometer and a digital vernier gauge.
Left connected, 4 weeks battery life:-(

--
Tim Lamb

Renata (switzerland) used to be the battery of choice for cameras
back in the days of film when silver oxide batteries were needed.

Andrew

On 04/10/2020 09:48, Brian Gaff (Sofa) wrote:
Yes, I've had the old black pea in a pack. I did send it back and got a free
new pack. No mention of fake. This was the old Energiser brand, used to be
Ever Ready I'd imagine, which when you think of it was a lie in the name, as
in the old days, even when they rebranded to Berec was not true. Most
Japanese batteries of the same era outperformed them. Duracell outperform
Energisers as well, indeed Sainsbury's own brand out perform energisers!
Brian

Tim Lamb has brought this to us :
and a digital vernier gauge. Left connected, 4 weeks battery life:-(

My two verniers last around a year, before needing new batteries, but
then I don't handle the replacement batteries with my fingers :-)

Tim Lamb wrote:
In message , Paul
writes
Snip

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Some battery powered devices have a constant battery drain despite being
*switched off*.

My two are a pistol grip laser thermometer and a digital vernier gauge.
Left connected, 4 weeks battery life:-(


If its the Aldi/Lidl one, Ive learnt to always pop the battery cover
before putting it away.

Tim

--
Please don't feed the trolls

After serious thinking Brian Gaff (Sofa) wrote :
They still got tired though and would enter that flash on and off behaviour,
first noticeable in the cold. I'd imagine the particles inside did something
to the electrodes and or the phosphor on the inside of the tube after some
time.

They don't use the heaters, except as as electorodes. The strike occurs
as a result of the high impedance, but high voltage.

If running floro tubes from a battery inverter circuit, the tubes tend
to blacken at one end, due to the ac not being a truelly balanced ac.
The average current flow will be in one direction, which will cause
blackening at one end of the tube and sometimes difficulty getting them
to strike. Simple answer, swap the tube end for end.

In message , Harry Bloomfield
writes
Tim Lamb has brought this to us :
and a digital vernier gauge. Left connected, 4 weeks battery life:-(

My two verniers last around a year, before needing new batteries, but
then I don't handle the replacement batteries with my fingers :-)

Mostly I use a simple vernier: the digital lives in a case with the 2302
battery removed.

The thermometer might get used twice a year checking the underfloor
heating (noticeable 2-4 deg. C difference from pipe to gap) and related
jobs. PP8 left disconnected

--
Tim Lamb

On 04/10/2020 17:52, Tim+ wrote:

If its the Aldi/Lidl one, Ive learnt to always pop the battery cover
before putting it away.

+1

The original battery bought many years ago has been in contact with my
fingers every time I remove and reinsert it and is still showing 1.5
volts after all these years.

On 03/10/2020 20:50, Tim Lamb wrote:
In message , Paul
writes
Snip

Some cells are knackered in the package. I was sold a
CR2032 at the mall, which was dead about a day after I
got it, which meant the product had been sitting in
that store for 10+ years. Or, it was a counterfeit
of a very inferior nature. No amount of fingerprints
would be responsible for that. Another cell purchased
elsewhere, behaved properly. It's not like I had
premature failures one after another, just the one
cell that was knackered, out of the package.

Some battery powered devices have a constant battery drain despite being
*switched off*.

My two are a pistol grip laser thermometer and a digital vernier gauge.
Left connected, 4 weeks battery life:-(

Yeah, those chinesium digital calipers seem famous for that. Mine are
the same. I get the feeling it would probably be cheaper to stump up for
the Mitutoyo[1] in the first place and not buy batteries by the shed load!

[1] in fact no, I just looked at the prices - that would buy a serious
amount of batteries!

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article ,
John Rumm wrote:
Yeah, those chinesium digital calipers seem famous for that. Mine are
the same. I get the feeling it would probably be cheaper to stump up for
the Mitutoyo[1] in the first place and not buy batteries by the shed
load!

Quite - that's what my digital calipers is. Batteries seem to last forever
- even when left switched on.

--
*It ain't the size, it's... er... no, it IS ..the size.

Dave Plowman London SW
To e-mail, change noise into sound.

Snip

I recently installed a (Rechargeable) button style battery in a central
heating programmer.

The original had 3 little legs welded to the case. The replacement was just
under £10 from the bay of the flea. Or, I could get what looked identical
but legless
For £2.99....

So, I tacked some legs onto the replacement with solder and then held the
battery in the jaws of a pair of snipe nosed pliers while I nailed it in
place on the PCB.

Then thought €œHmmm. Perhaps I shouldve insulated the Pilar tips prior to
grabbing both sides of the battery!€�

The battery was a bit warm from the soldering and / or shorting, but seems
to have survived the experience.