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malua mada!
Guest

Wed Feb 13, 2019 4:45 am   



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

Quote:

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?

Quote:
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.

Quote:

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.

Quote:
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?


Quote:
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.

Mike
Guest

Wed Feb 13, 2019 6:45 am   



On 2/12/2019 7:26 PM, malua mada! wrote:
Quote:
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.
Quote:

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.
Quote:


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.
Quote:

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.

malua mada!
Guest

Wed Feb 13, 2019 7:45 am   



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

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.



Quote:

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.

Mike
Guest

Wed Feb 13, 2019 10:45 pm   



On 2/12/2019 10:12 PM, malua mada! wrote:
Quote:
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-Rechargeable-Batteries-Battery-Charger/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.
Quote:


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.


malua mada!
Guest

Thu Feb 14, 2019 6:45 am   



On Wednesday, February 13, 2019 at 12:48:23 PM UTC-8, Mike wrote:
Quote:
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 Smile

Mike
Guest

Thu Feb 14, 2019 7:45 am   



On 2/13/2019 9:01 PM, malua mada! wrote:
Quote:
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.

Martin Brown
Guest

Thu Feb 14, 2019 12:45 pm   



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.
Quote:

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.
Quote:

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

Jeff Liebermann
Guest

Thu Feb 14, 2019 7:45 pm   



On Thu, 14 Feb 2019 11:16:24 +0000, Martin Brown
<'''newspam'''@nezumi.demon.co.uk> wrote:

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

pfjw@aol.com
Guest

Thu Feb 14, 2019 8:45 pm   



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

Jeff Liebermann
Guest

Thu Feb 14, 2019 10:45 pm   



On Thu, 14 Feb 2019 10:48:54 -0800 (PST), "pfjw_at_aol.com"
<peterwieck33_at_gmail.com> wrote:

Quote:
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.

Quote:
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 jeffl_at_cruzio.com
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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