Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default 9v Batteries

Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!! Even just sitting in their original packaging many years before
their use by date. These have ruined many devices. And NO I am not
spending all my time removing and inserting batteries in all my devices.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs. Duracell and Kirkland have Junk battery seals. I have years
of experience using these batteries hoping they would fix the seals, but
no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.

--- news://freenews.netfront.net/ - complaints: ---
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Default 9v Batteries

On Monday, February 11, 2019 at 12:44:28 PM UTC-5, OGEE wrote:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.


The best brands are those that guarantee both their products and the devices they go into.

I once had a Civil-Defense surplus Geiger counter that I purchased for $10 at a surplus auction. It took two (2) D-size batteries, which I duly inserted. My wife collected Fiesta-Ware at the time, and those pieces that were radioactive would not be used for food purposes. Most of the time, the thing sat in a closet, until one day I took it out and checked it - to find out that the two Eveready Alkaline batteries had leaked all over the innards.

Off it went to Eveready. Ten (10) days later, I received a check for $368.97 + the original postage, and a polite note stating that the cost offered was the original contract price to The Civil Defense people in 1963, and the postage - along with the admonition that I should not leave batteries in valuable idle equipment. Point taken.

Some time later, a 4-cell Maglite with Duracell batteries went off to Duracell. Took a bit longer, two (2) weeks. Back comes a new Maglite, and the old one fully cleaned and operating, together with fresh batteries.

Do you think that we will ever use anything other than these brands?

Peter Wieck
Melrose Park, PA
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Default 9v Batteries

On 02/11/2019 09:44 AM, OGEE wrote:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!! Even just sitting in their original packaging many years before
their use by date. These have ruined many devices. And NO I am not
spending all my time removing and inserting batteries in all my devices.


I was shocked to see the Kirkland leakage. I thought Costco chose better.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs. Duracell and Kirkland have Junk battery seals. I have years
of experience using these batteries hoping they would fix the seals, but
no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.


You might want to skip Maxell too -- every single one I've used has
leaked, including when it was still in the package.

I also bought some of the Duracell 'Eneloop-like' batteries, which do
NOT hold a charge for almost a year like they're supposed to; maybe a
few weeks or months -- I use my camera infrequently now so I can't be
accurate.

--
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Subscribe today to "Fire in the Hole - the Quarterly Journal
for Incinerator Toilet Enthusiasts" -- Andrew
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Default 9v Batteries

On 2/11/2019 9:44 AM, OGEE wrote:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!!Â*Â* Even just sitting in their original packaging many years before
their use by date.Â* These have ruined many devices.Â* And NO I am not
spending all my time removing and inserting batteries in all my devices.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs.Â*Â* Duracell and KirklandÂ* have Junk battery seals.Â* I have years
of experience using these batteries hoping they would fix the seals, but
no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.

--- news://freenews.netfront.net/ - complaints: ---


Depends on your application.
3 years ago I switched to EBL rechargeable lithium 9V batteries.
I use 'em in low drain devices like multimeters.
Haven't had to charge any of 'em yet.
They're rated at 600mAh, but I don't have any experience with high drain
usage.
Downside is that your device has to work down to 7V or so.
More expensive initially, but can have lower cost over the long haul.

Back in the day, I tried rechargeable 7.2V NiCds. Mostly useless.
The 8.4V 7-cell NiMH were better, but self discharge was an issue.
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Default 9v Batteries

OGEE wrote:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!!Â*Â* Even just sitting in their original packaging many years before
their use by date.Â* These have ruined many devices.Â* And NO I am not
spending all my time removing and inserting batteries in all my devices.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs.Â*Â* Duracell and KirklandÂ* have Junk battery seals.Â* I have years
of experience using these batteries hoping they would fix the seals, but
no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.

--- news://freenews.netfront.net/ - complaints: ---

Try Dollar Tree, fifty cents each. For best battery results, ANY
brand, store in refrigerator crisper. Like new 1 yr later..



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Default 9v Batteries

On Mon, 11 Feb 2019 14:06:06 -0800, Mike wrote:

3 years ago I switched to EBL rechargeable lithium 9V batteries.
I use 'em in low drain devices like multimeters.
Haven't had to charge any of 'em yet.
They're rated at 600mAh, but I don't have any experience with high drain
usage.
Downside is that your device has to work down to 7V or so.
More expensive initially, but can have lower cost over the long haul.

Back in the day, I tried rechargeable 7.2V NiCds. Mostly useless.
The 8.4V 7-cell NiMH were better, but self discharge was an issue.


I did exactly the same thing. Most of mine live in small instruments,
digital clocks, and portable radios now use EBL 9V LiIon batteries.
However, I have seen a few problems:
1. Some bulge when recharged. If there's expansion room in the
battery compartment, no problem. Otherwise, it might jam the battery
in the battery compartment.
2. I bought 10 of these batteries for about $40.
https://www.ebay.com/itm/EBL-Lot-of-600mAh-9V-Volt-6F22-Li-ion-Rechargeable-Batteries-High-Volume-1-20pcs/273615893492
I've only used 6 of these so far. 1 has failed the first time I tried
to charge it. The other 5 have survived about 3 recharges each
without incident. Reliability and quality seem to be an issue with
EBL batteries:
https://www.amazon.com/EBL-Rechargeable-Batteries-Lithium-4-Packs/dp/B00EJKIDHE/#customerReviews
3. Discharge test shows a bit low at 550 ma-hrs.
4. One of my cheap DVM's (Harbor Freight) quits before the battery
hits minimum voltage (about 6.8V).

EBL seems to be the least disgusting of the various 9V LiIon
batteries:
"#45 - 9V Li-ion batteries: capacity testing"
https://www.youtube.com/watch?v=9A06SPUF8i8

The good news is that I no longer trash instruments and equipment with
leaky alkaline batteries:
http://802.11junk.com/jeffl/crud/Kirkland-AAA-leak.jpg


--
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http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default 9v Batteries

On 2/11/2019 5:34 PM, Jeff Liebermann wrote:
On Mon, 11 Feb 2019 14:06:06 -0800, Mike wrote:

3 years ago I switched to EBL rechargeable lithium 9V batteries.
I use 'em in low drain devices like multimeters.
Haven't had to charge any of 'em yet.
They're rated at 600mAh, but I don't have any experience with high drain
usage.
Downside is that your device has to work down to 7V or so.
More expensive initially, but can have lower cost over the long haul.

Back in the day, I tried rechargeable 7.2V NiCds. Mostly useless.
The 8.4V 7-cell NiMH were better, but self discharge was an issue.


I did exactly the same thing. Most of mine live in small instruments,
digital clocks, and portable radios now use EBL 9V LiIon batteries.
However, I have seen a few problems:
1. Some bulge when recharged. If there's expansion room in the
battery compartment, no problem. Otherwise, it might jam the battery
in the battery compartment.
2. I bought 10 of these batteries for about $40.
https://www.ebay.com/itm/EBL-Lot-of-600mAh-9V-Volt-6F22-Li-ion-Rechargeable-Batteries-High-Volume-1-20pcs/273615893492
I've only used 6 of these so far. 1 has failed the first time I tried
to charge it. The other 5 have survived about 3 recharges each
without incident. Reliability and quality seem to be an issue with
EBL batteries:


I did have a problem with the first two I bought.
EBL sent me two more, no questions asked.
No problem with those.

I took the bad one apart. Turned out to be a balance problem and the
battery management shut it down. Balanced the cells and now it has been
working fine since.

I didn't buy the charger. I just charged 'em at low current to 8.2V.

https://www.amazon.com/EBL-Rechargeable-Batteries-Lithium-4-Packs/dp/B00EJKIDHE/#customerReviews
3. Discharge test shows a bit low at 550 ma-hrs.
4. One of my cheap DVM's (Harbor Freight) quits before the battery
hits minimum voltage (about 6.8V).

EBL seems to be the least disgusting of the various 9V LiIon
batteries:
"#45 - 9V Li-ion batteries: capacity testing"
https://www.youtube.com/watch?v=9A06SPUF8i8

The good news is that I no longer trash instruments and equipment with
leaky alkaline batteries:
http://802.11junk.com/jeffl/crud/Kirkland-AAA-leak.jpg



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Default 9v Batteries

Any battery leaks due to a spurious // resistor.
When in use, there also is a spurious series resistor.

OGEE a écrit le 11/02/2019 Ã* 18:44Â*:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!!Â*Â* Even just sitting in their original packaging many years before
their use by date.Â* These have ruined many devices. And NO I am not
spending all my time removing and inserting batteries in all my devices.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs.Â*Â* Duracell and KirklandÂ* have Junk battery seals.Â* I have years
of experience using these batteries hoping they would fix the seals,
but no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.

--- news://freenews.netfront.net/ - complaints: ---


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Default 9v Batteries

On equipment where the 9V battery is attached with a snap on connector
with wire leads, I put the battery in a small zip-lock bag. Of course
it can't be done in units where the battery connections are fixed to the
case.

Regards,
Tim


On 2/11/2019 12:44 PM, OGEE wrote:
Looking for less expensive 9v alkaline battery.

Please suggest best brands.

I usually buy eight or so at a time.

Forget Duracell as I have given up on Duracell and Kirkland, THEY LEAK
!!!Â*Â* Even just sitting in their original packaging many years before
their use by date.Â* These have ruined many devices.Â* And NO I am not
spending all my time removing and inserting batteries in all my devices.

I have totally dropped Duracell and Kirkland for all my AA and AAA
needs.Â*Â* Duracell and KirklandÂ* have Junk battery seals.Â* I have years
of experience using these batteries hoping they would fix the seals, but
no they just keep destroying my devices.

Amazon sells many brands but there is unfortunately no durability
comparison this or other products.

--- news://freenews.netfront.net/ - complaints: ---



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Default 9v Batteries

Never had a serious problem with 9V batteries.

It is the AA and AAA DURACELL and KIRKLAND batteries that leak big time.

Still looking for reliable AA and AAA.

Talking about 9V batteries is not helping !


--- news://freenews.netfront.net/ - complaints: ---


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Default 9v Batteries

Want less expensive but reliable 9V, AA and AAA batteries.

Cannot use so called "9V" Li batteries.

In some cases where it will work (physical fit-wise), I use a AA battery
pack carrier with the 9V snaps and get very long life battery usage.


--- news://freenews.netfront.net/ - complaints: ---
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Default 9v Batteries

OK - I will state the obvious again.

a) ALL batteries leak to some extent. Irrespective of brand or use.
b) What is important is what are the options WHEN (not IF) they leak.
c) A manufacturer which will stand behind their product and make the user whole is very nearly infinitely better than one that will not.
d) Let that distinction be the driver of whatever brand is chosen.

Peter Wieck
Melrose Park, PA
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On a sunny day (Tue, 12 Feb 2019 09:34:22 -0800) it happened OGEE
wrote in :

Never had a serious problem with 9V batteries.

It is the AA and AAA DURACELL and KIRKLAND batteries that leak big time.


Same here, duracell leaked and destroyed my bike light,
never used KIRKLAND.

Still looking for reliable AA and AAA.


I use Eneloop.
No self-discharge.
Even in this mouse... eneloop AA.

Where I need 2 AAA I use 3V lifepo4 AAA and a dummy (short) AAA battery,
or 3V liion and short the other one.

The lifepo4 AAA already held out for more than a year in a wireless keyboard.
Those do not catch fire,
but be careful with 3V liion, when full it is a bit more volts
than 2 x 1.5 (4.2 max), and those CAN catch fire.
If the app has a bit bad caps....

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Default 9v Batteries

On Monday, February 11, 2019 at 9:58:01 PM UTC-8, Mike wrote:


I took the bad one apart. Turned out to be a balance problem and the
battery management shut it down. Balanced the cells and now it has been
working fine since.

I didn't buy the charger. I just charged 'em at low current to 8.2V.


I just had a 9v EBL commit suicide in an old Fluke thermometer that has no low power shutoff. zero volts battery now at the terminals.

Took the battery apart. Both 702335 cells have 3.2 VDC and are wired in series... how would you "balance" that?
Positive side is connected straight to the connector. Negative side I can follow to an 8pin IC at pins (2,3) whereas opposite pins (6,7) are connected to where the power needs to go.
A wee little jumper perhaps?
The IC has no markings I can see... don't even know where number one pin is.
Measured ohms between the input and output pins and wouldn't you know it now it decides to conduct and I get voltage at the battery terminals. Darn.
THe question was going to be: how stupid / dangerous would installing a jumper be?

Thanks anyways
Fritz
believer in fixing by posting questions
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On 2/12/2019 2:18 PM, malua mada! wrote:
On Monday, February 11, 2019 at 9:58:01 PM UTC-8, Mike wrote:


I took the bad one apart. Turned out to be a balance problem and the
battery management shut it down. Balanced the cells and now it has been
working fine since.

I didn't buy the charger. I just charged 'em at low current to 8.2V.


I just had a 9v EBL commit suicide in an old Fluke thermometer that has no low power shutoff. zero volts battery now at the terminals.

Took the battery apart. Both 702335 cells have 3.2 VDC and are wired in series... how would you "balance" that?
Positive side is connected straight to the connector. Negative side I can follow to an 8pin IC at pins (2,3) whereas opposite pins (6,7) are connected to where the power needs to go.
A wee little jumper perhaps?
The IC has no markings I can see... don't even know where number one pin is.
Measured ohms between the input and output pins and wouldn't you know it now it decides to conduct and I get voltage at the battery terminals. Darn.
THe question was going to be: how stupid / dangerous would installing a jumper be?

The voltage measured zero because the BMS shut it off.
The ohm meter put enough volts on the BMS to get it to turn back on for
charging.

I can't think of any place a jumper will be useful.
Don't even think about shorting the BMS chip.
The cells are protected against under/over voltage. You need all that.
My limited experience with this battery is that it shuts off charge
when either cell reaches 4.2V.
I prefer to quit before that, around 4-4.1V/cell

Cells are probably matched, but still have significant differences at very
low voltages below the BMS cutoff. It's easy to get some imbalance down
there.
I'd charge it up to 3.8V/cell or so and then check balance and correct if
necessary before proceeding with a full charge.

Thanks anyways
Fritz
believer in fixing by posting questions

This is what's inside mine.

https://imgur.com/pAjauT7

I poked a tiny hole in the side of the package so I could poke a probe in
and access the point where two batteries connect in series.
If I ever need it again, I can use that and the two 9V terminals
to charge each cell individually to 4V. I'm hoping that the
battery will shutdown output at a voltage higher than the voltage
that prevents charging. Not had to test that yet.

Maintaining balance is a proactive activity.
It's been three years. Probably should open up all the meters
and recharge 'em.


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On Tuesday, February 12, 2019 at 3:21:32 PM UTC-8, Mike wrote:


I can't think of any place a jumper will be useful.
Don't even think about shorting the BMS chip.


blush... isn't a bare metal battery better than a dead one?

The cells are protected against under/over voltage. You need all that.
My limited experience with this battery is that it shuts off charge
when either cell reaches 4.2V.
I prefer to quit before that, around 4-4.1V/cell


I have a little 9V charger, blissfully ignorant of balancing acts.


https://imgur.com/pAjauT7

I poked a tiny hole in the side of the package so I could poke a probe in
and access the point where two batteries connect in series.


Mine looks the same. I totally missed the tap to the series connection there.

If I ever need it again, I can use that and the two 9V terminals
to charge each cell individually to 4V. I'm hoping that the
battery will shutdown output at a voltage higher than the voltage
that prevents charging. Not had to test that yet.

Maintaining balance is a proactive activity.

(swaying precariously) tisn't what happy consumers sposed to have to do?

It's been three years. Probably should open up all the meters
and recharge 'em.


amen! and get rid of the devices that just stay on to the last millivolt.
Meanwhile, I appreciate the knowledge that allows me to wake these (still costly) batteries from their self induced coma... wish it were easier.

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On 2/12/2019 7:26 PM, malua mada! wrote:
On Tuesday, February 12, 2019 at 3:21:32 PM UTC-8, Mike wrote:


I can't think of any place a jumper will be useful.
Don't even think about shorting the BMS chip.


blush... isn't a bare metal battery better than a dead one?


No, it isn't. Lithium batteries need a lot of care.

The cells are protected against under/over voltage. You need all that.
My limited experience with this battery is that it shuts off charge
when either cell reaches 4.2V.
I prefer to quit before that, around 4-4.1V/cell


I have a little 9V charger, blissfully ignorant of balancing acts.

"Little charger" is too vague to be helpful.
If it's a little charger designed to charge these EBL batteries,
you're good to go. If it ain't, don't use it.

The battery protection circuit seems to be reasonably good at shutting
off the charge at 8.4V, but that's the protection circuit, not normal
operation.


https://imgur.com/pAjauT7

I poked a tiny hole in the side of the package so I could poke a probe in
and access the point where two batteries connect in series.


Mine looks the same. I totally missed the tap to the series connection there.

If I ever need it again, I can use that and the two 9V terminals
to charge each cell individually to 4V. I'm hoping that the
battery will shutdown output at a voltage higher than the voltage
that prevents charging. Not had to test that yet.

Maintaining balance is a proactive activity.

(swaying precariously) tisn't what happy consumers sposed to have to do?

No, it's not. But that's the price we pay for the other benefits of the
technology.
If you keep the battery voltage within the shutdown limits, I expect it
works pretty well.
It's when you go beyond the safe limits that cell differences start
to manifest more visibly as imbalance.

It's been three years. Probably should open up all the meters
and recharge 'em.


amen! and get rid of the devices that just stay on to the last millivolt.
Meanwhile, I appreciate the knowledge that allows me to wake these (still costly) batteries from their self induced coma... wish it were easier.

It's not rocket science. Set your bench supply to 4.0V. Put a 1K
resistor in series with it and charge one cell at a time. When the
voltage across the resistor gets to about zero, do the other one.
I typically let the battery sit for a day after and check the balance again.
Tweak it till they're within a few millivolts after a rest.
That's overkill, but why not...

Note that I did NOT say take any random usb 5V charger and use it.
MUST stay below 4.2V.
If you don't have a way to generate 4ish volts, throw the batteries away.

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On Tuesday, February 12, 2019 at 8:53:54 PM UTC-8, Mike wrote:

I have a little 9V charger, blissfully ignorant of balancing acts.

"Little charger" is too vague to be helpful.
If it's a little charger designed to charge these EBL batteries,
you're good to go. If it ain't, don't use it.


bonai 9V 80 mA (x1) 50 mA (x2) charger. brought the patient up to 7.68 volts. which is what one has to accept for 9V these days? or anyhow below 8.4V from what you write.




amen! and get rid of the devices that just stay on to the last millivolt.
Meanwhile, I appreciate the knowledge that allows me to wake these (still costly) batteries from their self induced coma... wish it were easier.

It's not rocket science. Set your bench supply to 4.0V. Put a 1K
resistor in series with it and charge one cell at a time. When the
voltage across the resistor gets to about zero, do the other one.
I typically let the battery sit for a day after and check the balance again.
Tweak it till they're within a few millivolts after a rest.
That's overkill, but why not...

Note that I did NOT say take any random usb 5V charger and use it.
MUST stay below 4.2V.
If you don't have a way to generate 4ish volts, throw the batteries away.


nah there's a LM317 waiting to be tickled...

BTW I used anvil type pruning shears to open the battery case. Good force, good control.
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On 2/12/2019 10:12 PM, malua mada! wrote:
On Tuesday, February 12, 2019 at 8:53:54 PM UTC-8, Mike wrote:

I have a little 9V charger, blissfully ignorant of balancing acts.

"Little charger" is too vague to be helpful.
If it's a little charger designed to charge these EBL batteries,
you're good to go. If it ain't, don't use it.


bonai 9V 80 mA (x1) 50 mA (x2) charger. brought the patient up to 7.68 volts. which is what one has to accept for 9V these days? or anyhow below 8.4V from what you write.

If you look here
https://www.amazon.com/EBL-Rechargea.../dp/B079G37Y61

you will see
Battery: 6F22 9V 600mAh rechargeable li-ion batteries, note that all 9v
li-ion batteries' full voltage is 8.4V

You have the battery apart. What's the voltage on each individual cell?
If it's not the same, make it so.


amen! and get rid of the devices that just stay on to the last millivolt.
Meanwhile, I appreciate the knowledge that allows me to wake these (still costly) batteries from their self induced coma... wish it were easier.

It's not rocket science. Set your bench supply to 4.0V. Put a 1K
resistor in series with it and charge one cell at a time. When the
voltage across the resistor gets to about zero, do the other one.
I typically let the battery sit for a day after and check the balance again.
Tweak it till they're within a few millivolts after a rest.
That's overkill, but why not...

Note that I did NOT say take any random usb 5V charger and use it.
MUST stay below 4.2V.
If you don't have a way to generate 4ish volts, throw the batteries away.


nah there's a LM317 waiting to be tickled...

BTW I used anvil type pruning shears to open the battery case. Good force, good control.


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On Wednesday, February 13, 2019 at 12:48:23 PM UTC-8, Mike wrote:
You have the battery apart. What's the voltage on each individual cell?
If it's not the same, make it so.


3.823 3.826 :-)





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On 2/13/2019 9:01 PM, malua mada! wrote:
On Wednesday, February 13, 2019 at 12:48:23 PM UTC-8, Mike wrote:
You have the battery apart. What's the voltage on each individual cell?
If it's not the same, make it so.


3.823 3.826 :-)



That's gonna give you significantly reduced capacity.
If it were me, I'd set up the bench supply to 8.2V with a 50mA current
limit.
Hook that to the battery and again measure the cell voltages while charging.
That will give you an approximation to the internal resistance of the cells.

Increased resistance will cause the BMT chip to shut off charging
at a lower cell resting voltage.

Let it charge and see if it gets to 8.2V without shutting off.
They're rated at 8.4V, but I usually don't push 'em that hard.
It's difficult to know exactly what chemistry is used, but
lower voltage should improve cell life.

Another possibility is that the charger is crap. It has to do some
tests and make assumptions about which technology you're charging.
It may be getting it wrong.

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Default 9v Batteries

On 12/02/2019 17:34, OGEE wrote:
Never had a serious problem with 9V batteries.


I have had the odd one go bad. Usually left in something for too long.

It is the AA and AAA DURACELL and KIRKLAND batteries that leak big time.

Still looking for reliable AA and AAA.


At least in the UK I have found that Kodak's cheapest nastiest batteries
survive in high current drain applications where Duracells have leaked
on me. EveryReady & Panasonic also seem to be OK at least in the UK.

Talking about 9V batteries is not helping !


I won't use Duracell any more. I can't tell if it is a problem with high
quality counterfeit or their actual genuine manufacture batteries. There
was a time in the past when they were the copper topped gold standard!

--
Regards,
Martin Brown
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On Thu, 14 Feb 2019 11:16:24 +0000, Martin Brown
wrote:

I won't use Duracell any more. I can't tell if it is a problem with high
quality counterfeit or their actual genuine manufacture batteries. There
was a time in the past when they were the copper topped gold standard!


http://www.learnbydestroying.com/jeffl/pics/Duracell/index.html
Boom when shorted, probably because the gas vent plug was either
defective or missing. I didn't do the test or take the photos, so I
wasn't able to determine if they were real Duracell Procell or
counterfeit.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default 9v Batteries

About the only sure method I have found to determine what is counterfeit and what is real, other than by very close examination of the 'fit and finish' is the weight.

Real batteries are typically significantly heavier than the fakes, even discernible between two AAA types. And if you have a 4, 6 or 10 pack to compare, it is even more obvious.

You would also find out when you send that damaged piece of equipment back to Duracell or Eveready and have them inform you whether the batteries are real or not.

Peter Wieck
Melrose Park, PA
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Default 9v Batteries

On Thu, 14 Feb 2019 10:48:54 -0800 (PST), "
wrote:

About the only sure method I have found to determine what is counterfeit
and what is real, other than by very close examination of the 'fit and
finish' is the weight.

Real batteries are typically significantly heavier than the fakes, even
discernible between two AAA types. And if you have a 4, 6 or 10 pack
to compare, it is even more obvious.


Yeah, that worked for a while with LiIon 18650 cells.
https://www.instructables.com/id/How-to-know-a-fake-18650-battery/
Then, I started getting cells that all weighed about 65 grams, which
is rather high for an 18650. So, I cut one apart and found that it
was topped off with sand and some hot melt glue to hold the sand in
place. Foiled again.

You would also find out when you send that damaged piece of equipment
back to Duracell or Eveready and have them inform you whether the
batteries are real or not.


In this case, the friend that sent me the photos had already thrown
out the 9V battery. It didn't explode inside any equipment. I blew
up on his incredibly messy desk/workbench when the exposed terminals
were shorted by something conductive. If I had possession of the
remains, I would have doing my own autopsy on the battery, instead of
sending it to the manufacturer.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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