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Issue with notebook (maybe the battery?)

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  Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-25 17:50 +0100
    Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-03-25 20:40 +0100
      Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-25 22:00 +0100
    Re: Issue with notebook (maybe the battery?) Joe <joe@jretrading.com> - 2017-03-25 22:40 +0100
      Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-25 23:40 +0100
        Re: Issue with notebook (maybe the battery?) Eike Lantzsch <zp6cge@gmx.net> - 2017-03-26 00:20 +0100
          Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-26 04:50 +0200
        Re: Issue with notebook (maybe the battery?) Richard Owlett <rowlett@cloud85.net> - 2017-03-26 11:50 +0200
          Re: Issue with notebook (maybe the battery?) <tomas@tuxteam.de> - 2017-03-26 12:10 +0200
            Re: Issue with notebook (maybe the battery?) Joe <joe@jretrading.com> - 2017-03-26 13:00 +0200
              Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-26 22:10 +0200
                Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-03-27 05:20 +0200
                  Re: Issue with notebook (maybe the battery?) <tomas@tuxteam.de> - 2017-03-27 10:00 +0200
                  Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-28 20:50 +0200
                    Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-03-28 21:30 +0200
            Re: Issue with notebook (maybe the battery?) cbannister@slingshot.co.nz - 2017-04-03 14:20 +0200
          Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-26 21:40 +0200
            Re: Issue with notebook (maybe the battery?) Joe <joe@jretrading.com> - 2017-03-26 22:50 +0200
              Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-27 20:00 +0200
                Re: Issue with notebook (maybe the battery?) Joe <joe@jretrading.com> - 2017-03-27 21:10 +0200
                  Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-28 19:20 +0200
                    [OT] Re: Issue with notebook (maybe the battery?) Joe <joe@jretrading.com> - 2017-03-28 19:50 +0200
                      Re: [OT] Re: Issue with notebook (maybe the battery?) <tomas@tuxteam.de> - 2017-03-28 21:40 +0200
                        Re: [OT] Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-03-30 22:40 +0200
                          Re: [OT] Re: Issue with notebook (maybe the battery?) kAt <giathnygeia@openmailbox.org> - 2017-03-31 00:20 +0200
    Re: Issue with notebook (maybe the battery?) Stefan Monnier <monnier@iro.umontreal.ca> - 2017-03-27 05:50 +0200

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#179311 — Issue with notebook (maybe the battery?)

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Hi all!

Last night, when I was going to close my notebook (with Jessie), I
unplugged the charger cable waiting for the notebook to automatically go
to sleep mode and surprisingly it turned off. It was a bit late so I
left the issue to check it out today.

I re-plugged the charger cable and KDE displays a message saying
"Charging ..." but the charge level does not exceed 38%.

Some observations:

* If I unplug the charger, the notebook turns off. I would expect it to
not turn off if the battery has a 38% charge.

* When I plug in the charger, I notice that the battery LED blinks green
for a few seconds (as if it was charging), then blinks orange for a
moment (as if the battery is low) and finally it goes out (as if it were
already loaded).

* If with the cable plugged in I go to the KDE option to sleep the
notebook, it works. But as soon as I disconnect the cable, the notebook
turns off.

Maybe it's a problem with the battery? Can you think of any other tests
I can do to identify the source of the problem?


Thanks in advance.

Kind regards,
Daniel

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#179320

On Sat 25 Mar 2017 at 13:42:11 (-0300), Daniel Bareiro wrote:
> Hi all!
> 
> Last night, when I was going to close my notebook (with Jessie), I
> unplugged the charger cable waiting for the notebook to automatically go
> to sleep mode and surprisingly it turned off. It was a bit late so I
> left the issue to check it out today.
> 
> I re-plugged the charger cable and KDE displays a message saying
> "Charging ..." but the charge level does not exceed 38%.
> 
> Some observations:
> 
> * If I unplug the charger, the notebook turns off. I would expect it to
> not turn off if the battery has a 38% charge.
> 
> * When I plug in the charger, I notice that the battery LED blinks green
> for a few seconds (as if it was charging), then blinks orange for a
> moment (as if the battery is low) and finally it goes out (as if it were
> already loaded).
> 
> * If with the cable plugged in I go to the KDE option to sleep the
> notebook, it works. But as soon as I disconnect the cable, the notebook
> turns off.
> 
> Maybe it's a problem with the battery? Can you think of any other tests
> I can do to identify the source of the problem?

Sounds like the battery has lost one of more of its cells.
A charge of 38% is not bad in itself, but if the voltage
isn't there, the computer won't run.

Do you have a file along the lines of /sys/class/power_supply/BAT0/uevent
that has more information in it than just the charge numbers?

Cheers,
David.

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#179323

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Hi, David.

On 25/03/17 16:34, David Wright wrote:

>> Hi all!
>>
>> Last night, when I was going to close my notebook (with Jessie), I
>> unplugged the charger cable waiting for the notebook to automatically go
>> to sleep mode and surprisingly it turned off. It was a bit late so I
>> left the issue to check it out today.
>>
>> I re-plugged the charger cable and KDE displays a message saying
>> "Charging ..." but the charge level does not exceed 38%.
>>
>> Some observations:
>>
>> * If I unplug the charger, the notebook turns off. I would expect it to
>> not turn off if the battery has a 38% charge.
>>
>> * When I plug in the charger, I notice that the battery LED blinks green
>> for a few seconds (as if it was charging), then blinks orange for a
>> moment (as if the battery is low) and finally it goes out (as if it were
>> already loaded).
>>
>> * If with the cable plugged in I go to the KDE option to sleep the
>> notebook, it works. But as soon as I disconnect the cable, the notebook
>> turns off.
>>
>> Maybe it's a problem with the battery? Can you think of any other tests
>> I can do to identify the source of the problem?
> 
> Sounds like the battery has lost one of more of its cells.
> A charge of 38% is not bad in itself, but if the voltage
> isn't there, the computer won't run.
> 
> Do you have a file along the lines of /sys/class/power_supply/BAT0/uevent
> that has more information in it than just the charge numbers?

Below copy the output of the values obtained by this file:

-----------------------------------------------------
$ cat /sys/class/power_supply/BAT0/uevent
POWER_SUPPLY_NAME=BAT0
POWER_SUPPLY_STATUS=Unknown
POWER_SUPPLY_PRESENT=1
POWER_SUPPLY_TECHNOLOGY=Li-ion
POWER_SUPPLY_CYCLE_COUNT=0
POWER_SUPPLY_VOLTAGE_MIN_DESIGN=10800000
POWER_SUPPLY_VOLTAGE_NOW=10938000
POWER_SUPPLY_POWER_NOW=0
POWER_SUPPLY_ENERGY_FULL_DESIGN=60000000
POWER_SUPPLY_ENERGY_FULL=48920000
POWER_SUPPLY_ENERGY_NOW=18790000
POWER_SUPPLY_CAPACITY=38
POWER_SUPPLY_CAPACITY_LEVEL=Critical
POWER_SUPPLY_MODEL_NAME=45N1107
POWER_SUPPLY_MANUFACTURER=L
POWER_SUPPLY_SERIAL_NUMBER= 4375
-----------------------------------------------------


I had also consulted this file, although it seems that it shows the same
information but with a different format:

-----------------------------------------------------
$ upower -i /org/freedesktop/UPower/devices/battery_BAT0
  native-path:          BAT0
  vendor:               L
  model:                45N1107
  serial:               4375
  power supply:         yes
  updated:              sáb 25 mar 2017 17:49:46 -03 (57 seconds ago)
  has history:          yes
  has statistics:       yes
  battery
    present:             yes
    rechargeable:        yes
    state:               charging
    warning-level:       none
    energy:              18,79 Wh
    energy-empty:        0 Wh
    energy-full:         48,92 Wh
    energy-full-design:  60 Wh
    energy-rate:         0 W
    voltage:             10,939 V
    percentage:          38%
    capacity:            81,5333%
    technology:          lithium-ion
    icon-name:          'battery-good-charging-symbolic'
-----------------------------------------------------


Thanks for your reply.

Kind regards,
Daniel

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#179327

On Sat, 25 Mar 2017 13:42:11 -0300
Daniel Bareiro <daniel-listas@gmx.net> wrote:

> Hi all!
> 
> Last night, when I was going to close my notebook (with Jessie), I
> unplugged the charger cable waiting for the notebook to automatically
> go to sleep mode and surprisingly it turned off. It was a bit late so
> I left the issue to check it out today.
> 
> I re-plugged the charger cable and KDE displays a message saying
> "Charging ..." but the charge level does not exceed 38%.
> 
> Some observations:
> 
> * If I unplug the charger, the notebook turns off. I would expect it
> to not turn off if the battery has a 38% charge.
> 
> * When I plug in the charger, I notice that the battery LED blinks
> green for a few seconds (as if it was charging), then blinks orange
> for a moment (as if the battery is low) and finally it goes out (as
> if it were already loaded).
> 
> * If with the cable plugged in I go to the KDE option to sleep the
> notebook, it works. But as soon as I disconnect the cable, the
> notebook turns off.
> 
> Maybe it's a problem with the battery? Can you think of any other
> tests I can do to identify the source of the problem?
> 

Quick question: how old is the battery? I've seen it alleged that
lithium batteries lose up to 20% of capacity a year, regardless of
charge cycles, and I certainly had a laptop battery which stopped
charging after about five years of reducing capacity. I also have a
netbook, of the same brand, which is more than seven years old and
still holds about half the charge it did when it was new.

Many people replace laptops in much less than five years, though
probably not people who run Linux on them.

-- 
Joe

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#179331

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Hi, Joe.

On 25/03/17 18:29, Joe wrote:

>> Hi all!
>>
>> Last night, when I was going to close my notebook (with Jessie), I
>> unplugged the charger cable waiting for the notebook to automatically
>> go to sleep mode and surprisingly it turned off. It was a bit late so
>> I left the issue to check it out today.
>>
>> I re-plugged the charger cable and KDE displays a message saying
>> "Charging ..." but the charge level does not exceed 38%.
>>
>> Some observations:
>>
>> * If I unplug the charger, the notebook turns off. I would expect it
>> to not turn off if the battery has a 38% charge.
>>
>> * When I plug in the charger, I notice that the battery LED blinks
>> green for a few seconds (as if it was charging), then blinks orange
>> for a moment (as if the battery is low) and finally it goes out (as
>> if it were already loaded).
>>
>> * If with the cable plugged in I go to the KDE option to sleep the
>> notebook, it works. But as soon as I disconnect the cable, the
>> notebook turns off.
>>
>> Maybe it's a problem with the battery? Can you think of any other
>> tests I can do to identify the source of the problem?

> Quick question: how old is the battery? I've seen it alleged that
> lithium batteries lose up to 20% of capacity a year, regardless of
> charge cycles, and I certainly had a laptop battery which stopped
> charging after about five years of reducing capacity. I also have a
> netbook, of the same brand, which is more than seven years old and
> still holds about half the charge it did when it was new.
> 
> Many people replace laptops in much less than five years, though
> probably not people who run Linux on them.

Thanks for your interest.

Checking the purchase invoices, I bought the notebook on September 19,
2013, and then changed the battery on November 2, 2015. So less than two
years ago I have this battery.

The notebook I use it practically every day and I leave it sleeping from
one day to the next so I do not have to open every application every
time. I'm not sure if that impacts so much on the battery life.

But in any case, in all this time, whenever the battery was charged, the
charge level was up to 100%. So just since yesterday I suddenly saw that
the load stayed at 38% and I started to experience this issue.

Kind regards,
Daniel

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#179332

On Saturday, 25 March 2017 19:29:59 -03 Daniel Bareiro wrote:
> Hi, Joe.
> 
> On 25/03/17 18:29, Joe wrote:
> >> Hi all!
> >> 
> >> Last night, when I was going to close my notebook (with Jessie), I
> >> unplugged the charger cable waiting for the notebook to automatically
> >> go to sleep mode and surprisingly it turned off. It was a bit late so
> >> I left the issue to check it out today.
> >> 
> >> I re-plugged the charger cable and KDE displays a message saying
> >> "Charging ..." but the charge level does not exceed 38%.
> >> 
> >> Some observations:
> >> 
> >> * If I unplug the charger, the notebook turns off. I would expect it
> >> to not turn off if the battery has a 38% charge.
> >> 
> >> * When I plug in the charger, I notice that the battery LED blinks
> >> green for a few seconds (as if it was charging), then blinks orange
> >> for a moment (as if the battery is low) and finally it goes out (as
> >> if it were already loaded).
> >> 
> >> * If with the cable plugged in I go to the KDE option to sleep the
> >> notebook, it works. But as soon as I disconnect the cable, the
> >> notebook turns off.
> >> 
> >> Maybe it's a problem with the battery? Can you think of any other
> >> tests I can do to identify the source of the problem?
> > 
> > Quick question: how old is the battery? I've seen it alleged that
> > lithium batteries lose up to 20% of capacity a year, regardless of
> > charge cycles, and I certainly had a laptop battery which stopped
> > charging after about five years of reducing capacity. I also have a
> > netbook, of the same brand, which is more than seven years old and
> > still holds about half the charge it did when it was new.
> > 
> > Many people replace laptops in much less than five years, though
> > probably not people who run Linux on them.
> 
> Thanks for your interest.
> 
> Checking the purchase invoices, I bought the notebook on September 19,
> 2013, and then changed the battery on November 2, 2015. So less than two
> years ago I have this battery.

Did you purchase an original battery?
Usually the spare original batteries come with the same container as the 
laptops. Consequently the "new" batteries are as old as the laptop. For that 
reason it is usually better to purchase after-market batteries which contain 
fresher cells.
> 
> The notebook I use it practically every day and I leave it sleeping from
> one day to the next so I do not have to open every application every
> time. I'm not sure if that impacts so much on the battery life.
> 
> But in any case, in all this time, whenever the battery was charged, the
> charge level was up to 100%. So just since yesterday I suddenly saw that
> the load stayed at 38% and I started to experience this issue.
> 
> Kind regards,
> Daniel


-- 
Eike Lantzsch ZP6CGE
Agencia Shopping del Sol
Casilla de Correo 13005
1749 Asuncion / Paraguay
Land-line: +595-21-553984
SIP-gate: +49 4131 9279632
Cell-phone: +595-971-696909
Wire: @eikelantzsch
Skype: eikelan

Zuviel Zucker ist ungesund. Daher:
Tragt den Zuckerberg ab!

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#179338

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Hi, Eike.

On 25/03/17 20:13, Eike Lantzsch wrote:

>>>> Last night, when I was going to close my notebook (with Jessie), I
>>>> unplugged the charger cable waiting for the notebook to automatically
>>>> go to sleep mode and surprisingly it turned off. It was a bit late so
>>>> I left the issue to check it out today.
>>>>
>>>> I re-plugged the charger cable and KDE displays a message saying
>>>> "Charging ..." but the charge level does not exceed 38%.
>>>>
>>>> Some observations:
>>>>
>>>> * If I unplug the charger, the notebook turns off. I would expect it
>>>> to not turn off if the battery has a 38% charge.
>>>>
>>>> * When I plug in the charger, I notice that the battery LED blinks
>>>> green for a few seconds (as if it was charging), then blinks orange
>>>> for a moment (as if the battery is low) and finally it goes out (as
>>>> if it were already loaded).
>>>>
>>>> * If with the cable plugged in I go to the KDE option to sleep the
>>>> notebook, it works. But as soon as I disconnect the cable, the
>>>> notebook turns off.
>>>>
>>>> Maybe it's a problem with the battery? Can you think of any other
>>>> tests I can do to identify the source of the problem?

>>> Quick question: how old is the battery? I've seen it alleged that
>>> lithium batteries lose up to 20% of capacity a year, regardless of
>>> charge cycles, and I certainly had a laptop battery which stopped
>>> charging after about five years of reducing capacity. I also have a
>>> netbook, of the same brand, which is more than seven years old and
>>> still holds about half the charge it did when it was new.
>>>
>>> Many people replace laptops in much less than five years, though
>>> probably not people who run Linux on them.

>> Thanks for your interest.
>>
>> Checking the purchase invoices, I bought the notebook on September 19,
>> 2013, and then changed the battery on November 2, 2015. So less than two
>> years ago I have this battery.

> Did you purchase an original battery?

Yes. The parts I purchased were always original from Lenovo. The part
number is 45N1107.

> Usually the spare original batteries come with the same container as the 
> laptops. Consequently the "new" batteries are as old as the laptop. For that 
> reason it is usually better to purchase after-market batteries which contain 
> fresher cells.

Yes, I guess so. With the battery that came with the notebook I had
problems a while later and that is why then, in November 2015, I had to
buy another one that is the one I am using now, as I mentioned in a
previous message. But I'm not sure if this other battery is having
problems too. Is there any clue in the outputs copied in an previous
message that would suggest that?


Thanks for your reply.

Kind regards,
Daniel

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#179346

On 03/25/2017 05:29 PM, Daniel Bareiro wrote:
> Hi, Joe.
>
> [snip]
>
> Checking the purchase invoices, I bought the notebook on September 19,
> 2013, and then changed the battery on November 2, 2015. So less than two
> years ago I have this battery.
>
> The notebook I use it practically every day and I leave it sleeping from
> one day to the next so I do not have to open every application every
> time. I'm not sure if that impacts so much on the battery life.

If it was a long term degradation, possibly. With some battery 
technology/technologies(?) there is a "memory" effect. If there is a 
repeated "shallow discharge"/recharge cycle ( sleep overnight followed 
by running during day with charger plugged in) the effective battery 
capacity will decrease. IIRC that applies to only one technology but 
can't remember which.


>
> But in any case, in all this time, whenever the battery was charged, the
> charge level was up to 100%. So just since yesterday I suddenly saw that
> the load stayed at 38% and I started to experience this issue.

That makes me think of a component failure. Likely the battery, but 
conceivably something in the laptop.

>
> Kind regards,
> Daniel
>

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#179349

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Sun, Mar 26, 2017 at 04:46:37AM -0500, Richard Owlett wrote:
> On 03/25/2017 05:29 PM, Daniel Bareiro wrote:
> >Hi, Joe.
> >
> >[snip]
> >
> >Checking the purchase invoices, I bought the notebook on September 19,
> >2013, and then changed the battery on November 2, 2015. So less than two
> >years ago I have this battery.
> >
> >The notebook I use it practically every day and I leave it sleeping from
> >one day to the next so I do not have to open every application every
> >time. I'm not sure if that impacts so much on the battery life.
> 
> If it was a long term degradation, possibly. With some battery
> technology/technologies(?) there is a "memory" effect. If there is a
> repeated "shallow discharge"/recharge cycle ( sleep overnight
> followed by running during day with charger plugged in) the
> effective battery capacity will decrease. IIRC that applies to only
> one technology but can't remember which.

That would be the nickel family (NiMH and its predecessors). Laptops
changed long ago (I'd venture somewhere in the 90-ies) to Li-whatever.

Those have other weak spots: overcharging shortens their lives,
especially being overcharged *and* higher temps. More overcharging
leads to fireworks. They *need* some electronics to take care of
that. Deep discharge is also fatal to their lifetimes.

Regards
- -- tomás
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#179353

On Sun, 26 Mar 2017 12:07:46 +0200
<tomas@tuxteam.de> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> On Sun, Mar 26, 2017 at 04:46:37AM -0500, Richard Owlett wrote:
> > On 03/25/2017 05:29 PM, Daniel Bareiro wrote:  
> > >Hi, Joe.
> > >
> > >[snip]
> > >
> > >Checking the purchase invoices, I bought the notebook on September
> > >19, 2013, and then changed the battery on November 2, 2015. So
> > >less than two years ago I have this battery.
> > >
> > >The notebook I use it practically every day and I leave it
> > >sleeping from one day to the next so I do not have to open every
> > >application every time. I'm not sure if that impacts so much on
> > >the battery life.  
> > 
> > If it was a long term degradation, possibly. With some battery
> > technology/technologies(?) there is a "memory" effect. If there is a
> > repeated "shallow discharge"/recharge cycle ( sleep overnight
> > followed by running during day with charger plugged in) the
> > effective battery capacity will decrease. IIRC that applies to only
> > one technology but can't remember which.  
> 
> That would be the nickel family (NiMH and its predecessors). Laptops
> changed long ago (I'd venture somewhere in the 90-ies) to Li-whatever.

Lithium isn't particularly sensitive to state and depth of charge,
apparently the optimal long-term storage state is about half-charge.
> 
> Those have other weak spots: overcharging shortens their lives,
> especially being overcharged *and* higher temps. More overcharging
> leads to fireworks. They *need* some electronics to take care of
> that. Deep discharge is also fatal to their lifetimes.

Complete discharge is instantly fatal, they can never wake up again.
All lithium cells have rudimentary electronics to cut off discharge
earlier than this, typically 2.8-3.0V per cell. Charging is relatively
complex, constant current of about half capacity to around 4.1V, then
constant voltage to fairly precise 4.2V, then when the current drops
below a certain level, cutoff.

It should be possible to leave a lithium battery permanently connected
to the charger. No 'trickle charge' will occur, no additional current
will flow until the cell voltage drops by a certain amount. But full
charge is not recommended for long-term storage.

Yes, I had to build a lithium battery into something a few years ago,
I had to learn how to charge it. 

-- 
Joe

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#179404

[Multipart message — attachments visible in raw view] — view raw

Hi, Tomás and Joe.

On 26/03/17 07:49, Joe wrote:

>>>> [snip]
>>>>
>>>> Checking the purchase invoices, I bought the notebook on September
>>>> 19, 2013, and then changed the battery on November 2, 2015. So
>>>> less than two years ago I have this battery.
>>>>
>>>> The notebook I use it practically every day and I leave it
>>>> sleeping from one day to the next so I do not have to open every
>>>> application every time. I'm not sure if that impacts so much on
>>>> the battery life.  

>>> If it was a long term degradation, possibly. With some battery
>>> technology/technologies(?) there is a "memory" effect. If there is a
>>> repeated "shallow discharge"/recharge cycle ( sleep overnight
>>> followed by running during day with charger plugged in) the
>>> effective battery capacity will decrease. IIRC that applies to only
>>> one technology but can't remember which.  

>> That would be the nickel family (NiMH and its predecessors). Laptops
>> changed long ago (I'd venture somewhere in the 90-ies) to Li-whatever.

> Lithium isn't particularly sensitive to state and depth of charge,
> apparently the optimal long-term storage state is about half-charge.

>> Those have other weak spots: overcharging shortens their lives,
>> especially being overcharged *and* higher temps. More overcharging
>> leads to fireworks. They *need* some electronics to take care of
>> that. Deep discharge is also fatal to their lifetimes.

> Complete discharge is instantly fatal, they can never wake up again.
> All lithium cells have rudimentary electronics to cut off discharge
> earlier than this, typically 2.8-3.0V per cell. Charging is relatively
> complex, constant current of about half capacity to around 4.1V, then
> constant voltage to fairly precise 4.2V, then when the current drops
> below a certain level, cutoff.
> 
> It should be possible to leave a lithium battery permanently connected
> to the charger. No 'trickle charge' will occur, no additional current
> will flow until the cell voltage drops by a certain amount. But full
> charge is not recommended for long-term storage.
> 
> Yes, I had to build a lithium battery into something a few years ago,
> I had to learn how to charge it. 

Thank you for sharing these interesting comments. I think some time I've
inadvertently consumed the entire battery charge (although this was
something that happened a long time ago, I think). Perhaps the
recommendation to avoid this is to check the "Enable Power Management"
option in KDE.

Do you think that of the information I showed in
/sys/class/power_supply/BAT0/uevent or
/org/freedesktop/UPower/devices/battery_BAT0 can be detected any
electrical problem with the battery?


Kind regards,
Daniel

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#179420

On Sun 26 Mar 2017 at 17:09:01 (-0300), Daniel Bareiro wrote:
> Hi, Tomás and Joe.
> 
> On 26/03/17 07:49, Joe wrote:
> 
> >>>> [snip]
> >>>>
> >>>> Checking the purchase invoices, I bought the notebook on September
> >>>> 19, 2013, and then changed the battery on November 2, 2015. So
> >>>> less than two years ago I have this battery.
> >>>>
> >>>> The notebook I use it practically every day and I leave it
> >>>> sleeping from one day to the next so I do not have to open every
> >>>> application every time. I'm not sure if that impacts so much on
> >>>> the battery life.  
> 
> >>> If it was a long term degradation, possibly. With some battery
> >>> technology/technologies(?) there is a "memory" effect. If there is a
> >>> repeated "shallow discharge"/recharge cycle ( sleep overnight
> >>> followed by running during day with charger plugged in) the
> >>> effective battery capacity will decrease. IIRC that applies to only
> >>> one technology but can't remember which.  
> 
> >> That would be the nickel family (NiMH and its predecessors). Laptops
> >> changed long ago (I'd venture somewhere in the 90-ies) to Li-whatever.
> 
> > Lithium isn't particularly sensitive to state and depth of charge,
> > apparently the optimal long-term storage state is about half-charge.
> 
> >> Those have other weak spots: overcharging shortens their lives,
> >> especially being overcharged *and* higher temps. More overcharging
> >> leads to fireworks. They *need* some electronics to take care of
> >> that. Deep discharge is also fatal to their lifetimes.
> 
> > Complete discharge is instantly fatal, they can never wake up again.
> > All lithium cells have rudimentary electronics to cut off discharge
> > earlier than this, typically 2.8-3.0V per cell. Charging is relatively
> > complex, constant current of about half capacity to around 4.1V, then
> > constant voltage to fairly precise 4.2V, then when the current drops
> > below a certain level, cutoff.
> > 
> > It should be possible to leave a lithium battery permanently connected
> > to the charger. No 'trickle charge' will occur, no additional current
> > will flow until the cell voltage drops by a certain amount. But full
> > charge is not recommended for long-term storage.
> > 
> > Yes, I had to build a lithium battery into something a few years ago,
> > I had to learn how to charge it. 
> 
> Thank you for sharing these interesting comments. I think some time I've
> inadvertently consumed the entire battery charge (although this was
> something that happened a long time ago, I think). Perhaps the
> recommendation to avoid this is to check the "Enable Power Management"
> option in KDE.

I didn't know you could. I thought the battery would stop supplying
current before that happened. I was under the impression that to get
any lower, you had to leave it empty so it could self-discharge.

I ran a laptop on a faulty battery for 17 months. Throughout that
period, the charge indicator flashed four yellows and a green. Apart
from running down quite quickly, there were no other signs of
distress. About a week before it finally gave up the ghost, I had the
same behaviour as yours: removing the power cable would kill the laptop.

The battery itself had a charge indicator when you pressed a button,
lighting a steady line of one to five LEDs. When it died, just the
2nd and 4th LEDs flashed on and off instead, and the laptop wouldn't
run at all.

Fortunately, I had a spare (smaller) battery of the same vintage which
is still going. (I won't say still going strong.) The laptop is also
showing its age: the display gives problems most of the time so I run
it hooked up to a monitor.

> Do you think that of the information I showed in
> /sys/class/power_supply/BAT0/uevent or
> /org/freedesktop/UPower/devices/battery_BAT0 can be detected any
> electrical problem with the battery?

The only obvious oddity I can see is POWER_SUPPLY_STATUS=Unknown but
I'm not sure I haven't seen that myself in the past, though probably
only momentarily. But the voltages you see are a bit suspicious.

I just ran this same laptop down to 7% capacity (takes about 20 minutes)
and it was down at 10.797 volts. On reconnecting the power, it rose to
11.7 volts within, say, 15 seconds (but still reading 7% of course).
So the low voltage you see with the charger attached might suggest
that the battery is loading the charger somewhat. (Unfortunately you
don't appear to get current amps, which may be related to Unknown above.)

So if I were you I'd be buying a new battery in case the machine won't
run when this old one completely fails. (I don't know about the wisdom
of running with no battery; anyway this laptop looks as if the underside
of the touchpad is very vulnerable when the battery is removed, and
you lose two feet.)

Cheers,
David.

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#179425

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Sun, Mar 26, 2017 at 10:08:10PM -0500, David Wright wrote:
> On Sun 26 Mar 2017 at 17:09:01 (-0300), Daniel Bareiro wrote:
> > Hi, Tomás and Joe.

[...]

> > Thank you for sharing these interesting comments. I think some time I've
> > inadvertently consumed the entire battery charge (although this was
> > something that happened a long time ago, I think). Perhaps the
> > recommendation to avoid this is to check the "Enable Power Management"
> > option in KDE.
> 
> I didn't know you could. I thought the battery would stop supplying
> current before that happened. I was under the impression that to get
> any lower, you had to leave it empty so it could self-discharge.

That's right: those things have a charge controller which should take
care of that (at both ends: overcharge, because *boom*, and that's
expensive for the manufacturer, ask Samsung [1]) and deep discharge.

Unless the charge controller is somehow defective -- and they are all
a bit, because it's a tradeoff: if you just allow 70% max charge
wrt what is usual, your battery pack will live quite a bit longer,
but you can't boast "8 hours" or something. I wouldn't expect that
from Lenovo, but what do I know?

regards
- -- t
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)

iEYEARECAAYFAljYxKsACgkQBcgs9XrR2kb/XACdFq+49NKjlcwpICJgH1cdQY2j
+L8An2guyN7z1N42aGJ3OGNu5Fp8Asg/
=ZFWi
-----END PGP SIGNATURE-----

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#179546

[Multipart message — attachments visible in raw view] — view raw

Hi, David.

On 27/03/17 00:08, David Wright wrote:

>>> Complete discharge is instantly fatal, they can never wake up again.
>>> All lithium cells have rudimentary electronics to cut off discharge
>>> earlier than this, typically 2.8-3.0V per cell. Charging is relatively
>>> complex, constant current of about half capacity to around 4.1V, then
>>> constant voltage to fairly precise 4.2V, then when the current drops
>>> below a certain level, cutoff.
>>>
>>> It should be possible to leave a lithium battery permanently connected
>>> to the charger. No 'trickle charge' will occur, no additional current
>>> will flow until the cell voltage drops by a certain amount. But full
>>> charge is not recommended for long-term storage.
>>>
>>> Yes, I had to build a lithium battery into something a few years ago,
>>> I had to learn how to charge it. 

>> Thank you for sharing these interesting comments. I think some time I've
>> inadvertently consumed the entire battery charge (although this was
>> something that happened a long time ago, I think). Perhaps the
>> recommendation to avoid this is to check the "Enable Power Management"
>> option in KDE.

> I didn't know you could. I thought the battery would stop supplying
> current before that happened. I was under the impression that to get
> any lower, you had to leave it empty so it could self-discharge.
> 
> I ran a laptop on a faulty battery for 17 months. Throughout that
> period, the charge indicator flashed four yellows and a green. Apart
> from running down quite quickly, there were no other signs of
> distress. About a week before it finally gave up the ghost, I had the
> same behaviour as yours: removing the power cable would kill the laptop.
> 
> The battery itself had a charge indicator when you pressed a button,
> lighting a steady line of one to five LEDs. When it died, just the
> 2nd and 4th LEDs flashed on and off instead, and the laptop wouldn't
> run at all.
> 
> Fortunately, I had a spare (smaller) battery of the same vintage which
> is still going. (I won't say still going strong.) The laptop is also
> showing its age: the display gives problems most of the time so I run
> it hooked up to a monitor.

Thank you for sharing these experiences. In my previous email I was
talking about a full discharge because that's what I thought happened
when I saw the KDE charge indicator after I plugged in the charger once
the notebook shut down abruptly because I did not have enable the
"Enable Power Management" option of KDE. That's why I thought that it
would avoid that situation happens again

>> Do you think that of the information I showed in
>> /sys/class/power_supply/BAT0/uevent or
>> /org/freedesktop/UPower/devices/battery_BAT0 can be detected any
>> electrical problem with the battery?

> The only obvious oddity I can see is POWER_SUPPLY_STATUS=Unknown but
> I'm not sure I haven't seen that myself in the past, though probably
> only momentarily. But the voltages you see are a bit suspicious.
> 
> I just ran this same laptop down to 7% capacity (takes about 20 minutes)
> and it was down at 10.797 volts. On reconnecting the power, it rose to
> 11.7 volts within, say, 15 seconds (but still reading 7% of course).
> So the low voltage you see with the charger attached might suggest
> that the battery is loading the charger somewhat. (Unfortunately you
> don't appear to get current amps, which may be related to Unknown above.)

I was observing these values:

------------------------------------------------------------------------
$ upower -i /org/freedesktop/UPower/devices/battery_BAT0
(...)
  battery
(...)
    percentage:          37%
    capacity:            81,5333%
(...)
------------------------------------------------------------------------

But I'm not sure if that will be indicator of something. "Percentage"
seems to be the battery charge level. Looking at the upower
documentation I found this [1]:

The "Percentage" property: The amount of energy left in the power source
expressed as a percentage between 0 and 100. Typically this is the same
as (energy - energy-empty) / (energy-full - energy-empty). However, some
primitive power sources are capable of only reporting percentages and in
this case the energy-* properties will be unset while this property is set.

The "Capacity" property: The capacity of the power source expressed as a
percentage between 0 and 100. The capacity of the battery will reduce
with age. A capacity value less than 75% is usually a sign that you
should renew your battery. Typically this value is the same as
(full-design / full) * 100. However, some primitive power sources are
not capable reporting capacity and in this case the capacity property
will be unset.

I was comparing the values with those of the original battery:

------------------------------------------------------------------------
# upower -i /org/freedesktop/UPower/devices/battery_BAT0
  native-path:
/sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:08/PNP0C09:00/PNP0C0A:00/power_supply/BAT0
  vendor:               SANYO
  model:                45N1001
  serial:               5581
  power supply:         yes
  updated:              Wed Nov 27 20:26:02 2013 (23 seconds ago)
  has history:          yes
  has statistics:       yes
  battery
    present:             yes
    rechargeable:        yes
    state:               fully-charged
    energy:              55.76 Wh
    energy-empty:        0 Wh
    energy-full:         55.81 Wh
    energy-full-design:  56.16 Wh
    energy-rate:         4.626 W
    voltage:             12.53 V
    percentage:          99.9104%
    capacity:            99.3768%
    technology:          lithium-ion
------------------------------------------------------------------------

For example, for the current battery the "energy-rate" value is
extremely low:

------------------------------------------------------------------------
(...)
  battery
    present:             yes
    rechargeable:        yes
    state:               charging
    warning-level:       none
    energy:              18,31 Wh
    energy-empty:        0 Wh
    energy-full:         48,92 Wh
    energy-full-design:  60 Wh
    energy-rate:         0,00728571 W
    voltage:             10,928 V
    percentage:          37%
    capacity:            81,5333%
    technology:          lithium-ion
    icon-name:          'battery-good-charging-symbolic'
------------------------------------------------------------------------


> So if I were you I'd be buying a new battery in case the machine won't
> run when this old one completely fails. (I don't know about the wisdom
> of running with no battery; anyway this laptop looks as if the underside
> of the touchpad is very vulnerable when the battery is removed, and
> you lose two feet.)

Yes, as I mentioned in another message in this thread, I have already
contacted the supplier to go asking for availability and prices.


Thanks for your reply.

Kind regards,
Daniel

[1] https://upower.freedesktop.org/docs/Device.html

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#179549

On Tue 28 Mar 2017 at 15:46:36 (-0300), Daniel Bareiro wrote:
> I was observing these values:
> 
> ------------------------------------------------------------------------
> $ upower -i /org/freedesktop/UPower/devices/battery_BAT0
> (...)
>   battery
> (...)
>     percentage:          37%
>     capacity:            81,5333%
> (...)
> ------------------------------------------------------------------------
> 
> But I'm not sure if that will be indicator of something. "Percentage"
> seems to be the battery charge level. Looking at the upower
> documentation I found this [1]:

Yes, I just looked at the earlier lines that I'm familiar with, viz.

POWER_SUPPLY_ENERGY_FULL_DESIGN=60000000
POWER_SUPPLY_ENERGY_FULL=48920000
POWER_SUPPLY_ENERGY_NOW=18790000

> Yes, as I mentioned in another message in this thread, I have already
> contacted the supplier to go asking for availability and prices.

I'll cross my fingers for you. Please do likewise as these are
the figures from one of my laptops:

Charger in:
POWER_SUPPLY_CHARGE_FULL_DESIGN=3800000
POWER_SUPPLY_CHARGE_FULL=872000
POWER_SUPPLY_CHARGE_NOW=3800000

Charger out:
POWER_SUPPLY_CHARGE_FULL_DESIGN=3800000
POWER_SUPPLY_CHARGE_FULL=872000
POWER_SUPPLY_CHARGE_NOW=828000

IOW my baseline after 8 years is about 20% capacity.

Cheers,
David.

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#179729

On Sun, Mar 26, 2017 at 12:07:46PM +0200, tomas@tuxteam.de wrote:
> On Sun, Mar 26, 2017 at 04:46:37AM -0500, Richard Owlett wrote:
> > On 03/25/2017 05:29 PM, Daniel Bareiro wrote:
> > >Hi, Joe.
> > >
> > >[snip]
> > >
> > >Checking the purchase invoices, I bought the notebook on September 19,
> > >2013, and then changed the battery on November 2, 2015. So less than two
> > >years ago I have this battery.
> > >
> > >The notebook I use it practically every day and I leave it sleeping from
> > >one day to the next so I do not have to open every application every
> > >time. I'm not sure if that impacts so much on the battery life.
> > 
> > If it was a long term degradation, possibly. With some battery
> > technology/technologies(?) there is a "memory" effect. If there is a
> > repeated "shallow discharge"/recharge cycle ( sleep overnight
> > followed by running during day with charger plugged in) the
> > effective battery capacity will decrease. IIRC that applies to only
> > one technology but can't remember which.
> 
> That would be the nickel family (NiMH and its predecessors). Laptops
> changed long ago (I'd venture somewhere in the 90-ies) to Li-whatever.

http://batteryuniversity.com/learn/archive/memory_myth_or_fact

-- 
The media's the most powerful entity on earth. 
They have the power to make the innocent guilty 
and to make the guilty innocent, and that's power.
 -- Malcolm X

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#179399

[Multipart message — attachments visible in raw view] — view raw

Hi, Richard.

On 26/03/17 06:46, Richard Owlett wrote:

>> [snip]
>>
>> Checking the purchase invoices, I bought the notebook on September 19,
>> 2013, and then changed the battery on November 2, 2015. So less than two
>> years ago I have this battery.
>>
>> The notebook I use it practically every day and I leave it sleeping from
>> one day to the next so I do not have to open every application every
>> time. I'm not sure if that impacts so much on the battery life.

> If it was a long term degradation, possibly. With some battery
> technology/technologies(?) there is a "memory" effect. If there is a
> repeated "shallow discharge"/recharge cycle ( sleep overnight followed
> by running during day with charger plugged in) the effective battery
> capacity will decrease. IIRC that applies to only one technology but
> can't remember which.

I remember that when I bought this battery, I was advised to leave the
charger plugged in for a little more than an hour after the charging
level reaches 100%. And for the subsequent times, try to avoid having
the charger plugged in when the battery charge level reaches 100%. So I
was following that criteria. What do you think about that?

>> But in any case, in all this time, whenever the battery was charged, the
>> charge level was up to 100%. So just since yesterday I suddenly saw that
>> the load stayed at 38% and I started to experience this issue.

> That makes me think of a component failure. Likely the battery, but
> conceivably something in the laptop.

Perhaps the ultimate test is going to a business where they have
original Lenovo components, ask them for a new battery to test it at the
moment with the notebook and, if all goes well, then buy it.

Thanks for your reply.

Kind regards,
Daniel

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#179406

On Sun, 26 Mar 2017 16:38:29 -0300
Daniel Bareiro <daniel-listas@gmx.net> wrote:

> Hi, Richard.
> 
> On 26/03/17 06:46, Richard Owlett wrote:
> 
> >> [snip]
> >>
> >> Checking the purchase invoices, I bought the notebook on September
> >> 19, 2013, and then changed the battery on November 2, 2015. So
> >> less than two years ago I have this battery.
> >>
> >> The notebook I use it practically every day and I leave it
> >> sleeping from one day to the next so I do not have to open every
> >> application every time. I'm not sure if that impacts so much on
> >> the battery life.  
> 
> > If it was a long term degradation, possibly. With some battery
> > technology/technologies(?) there is a "memory" effect. If there is a
> > repeated "shallow discharge"/recharge cycle ( sleep overnight
> > followed by running during day with charger plugged in) the
> > effective battery capacity will decrease. IIRC that applies to only
> > one technology but can't remember which.  
> 
> I remember that when I bought this battery, I was advised to leave the
> charger plugged in for a little more than an hour after the charging
> level reaches 100%. And for the subsequent times, try to avoid having
> the charger plugged in when the battery charge level reaches 100%. So
> I was following that criteria. What do you think about that?

I would hesitate to contradict a supplier, but a lithium battery
charger should not permit overcharging. It *must* not, as there is a
serious risk of fire or explosion, not just a reduction of life as
will occur with other types. The maximum charge voltage must be a fairly
precise 4.20V per cell, and really the only practical way to charge
these batteries is to use one of many specialised integrated circuits
designed to do just that.

There's a time sequence: first, with a completely discharged battery,
which will have been disconnected by its own internal electronics, a
significant current charge is given and the cell voltage monitored
(calculated for a multi-cell battery). If it does not exceed 3.0V
within a few minutes, the charger gives up and produce an error signal,
the battery is faulty. If all is well, the recommended charge current
for the cells, normally about half the capacity i.e. about a two-hour
charge, is applied until the voltage reaches about 4.1V/cell, when the
charger switches to a third mode to bring the output voltage to
precisely 4.2V. During this mode, as the cell reaches full charge, the
current drops away and when a particular value is reached, the charger
cuts off. No further charge will be applied until usage or
self-discharge of the cell reduces the voltage to below about 4.1V. If
a charger is connected to a battery that is already charged to between
3.0V and 4.1V per cell, phase two is immediately started, and if the
cell voltage is already between 4.1V and 4.2V, nothing will happen.
There is no continuous trickle-charge mode. Assuming, of course, the
charger is designed properly, and with a specialised IC, this is pretty
much guaranteed.

So a lot of warnings about overcharging, memory effect, about removing
the battery when external power is used, and suchlike, are hangovers
from the days of nickel battery technologies, and don't apply to
lithium. Conversely, the charger has to be matched to the battery
capacity, and there's no way to charge lithium batteries with any kind
of general-purpose charger, you need the supplier's own charger, which
may be built-in to the appliance.

> 
> >> But in any case, in all this time, whenever the battery was
> >> charged, the charge level was up to 100%. So just since yesterday
> >> I suddenly saw that the load stayed at 38% and I started to
> >> experience this issue.  
> 
> > That makes me think of a component failure. Likely the battery, but
> > conceivably something in the laptop.

Yes. The problem is that it's not possible to rig up a quick charging
test for lithium, or a dummy battery load to check the charger. With
other technologies, a current source powered from a higher voltage,
with a voltmeter, would give some idea of the battery state. 
> 
> Perhaps the ultimate test is going to a business where they have
> original Lenovo components, ask them for a new battery to test it at
> the moment with the notebook and, if all goes well, then buy it.
> 
Sadly, that's the only real test.

Something worth trying if you have access to a voltmeter: the battery
pack will have at least three terminals, maybe more, and a voltage
should be measurable across two of them. The voltage value may show a
missing (shorted) cell. Discharged as far as possible, a lithium cell
should be around 3.0V, and fully charged, 4.2V. The battery should be
marked as to how many cells it contains. If you get a reading of less
than 3.0V per cell, there is almost certainly a dead cell. Probably you
won't get a conclusive reading, if the charger thinks there's 38%
charge, then the volts per cell is probably higher than 3.0, which it
can be if one cell is missing but the others are well-charged.

-- 
Joe

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#179483

[Multipart message — attachments visible in raw view] — view raw

Hi, Joe.

>>>> Checking the purchase invoices, I bought the notebook on September
>>>> 19, 2013, and then changed the battery on November 2, 2015. So
>>>> less than two years ago I have this battery.
>>>>
>>>> The notebook I use it practically every day and I leave it
>>>> sleeping from one day to the next so I do not have to open every
>>>> application every time. I'm not sure if that impacts so much on
>>>> the battery life.  

>>> If it was a long term degradation, possibly. With some battery
>>> technology/technologies(?) there is a "memory" effect. If there is a
>>> repeated "shallow discharge"/recharge cycle ( sleep overnight
>>> followed by running during day with charger plugged in) the
>>> effective battery capacity will decrease. IIRC that applies to only
>>> one technology but can't remember which.  

>> I remember that when I bought this battery, I was advised to leave the
>> charger plugged in for a little more than an hour after the charging
>> level reaches 100%. And for the subsequent times, try to avoid having
>> the charger plugged in when the battery charge level reaches 100%. So
>> I was following that criteria. What do you think about that?

> I would hesitate to contradict a supplier, but a lithium battery
> charger should not permit overcharging. It *must* not, as there is a
> serious risk of fire or explosion, not just a reduction of life as
> will occur with other types. The maximum charge voltage must be a fairly
> precise 4.20V per cell, and really the only practical way to charge
> these batteries is to use one of many specialised integrated circuits
> designed to do just that.

I think he made that recommendation about disconnecting the charger when
the charge reaches 100% because he thought otherwise would affect the
battery life.

> There's a time sequence: first, with a completely discharged battery,
> which will have been disconnected by its own internal electronics, a
> significant current charge is given and the cell voltage monitored
> (calculated for a multi-cell battery). If it does not exceed 3.0V
> within a few minutes, the charger gives up and produce an error signal,
> the battery is faulty. If all is well, the recommended charge current
> for the cells, normally about half the capacity i.e. about a two-hour
> charge, is applied until the voltage reaches about 4.1V/cell, when the
> charger switches to a third mode to bring the output voltage to
> precisely 4.2V. During this mode, as the cell reaches full charge, the
> current drops away and when a particular value is reached, the charger
> cuts off. No further charge will be applied until usage or
> self-discharge of the cell reduces the voltage to below about 4.1V. If
> a charger is connected to a battery that is already charged to between
> 3.0V and 4.1V per cell, phase two is immediately started, and if the
> cell voltage is already between 4.1V and 4.2V, nothing will happen.
> There is no continuous trickle-charge mode. Assuming, of course, the
> charger is designed properly, and with a specialised IC, this is pretty
> much guaranteed.
>
> So a lot of warnings about overcharging, memory effect, about removing
> the battery when external power is used, and suchlike, are hangovers
> from the days of nickel battery technologies, and don't apply to
> lithium. Conversely, the charger has to be matched to the battery
> capacity, and there's no way to charge lithium batteries with any kind
> of general-purpose charger, you need the supplier's own charger, which
> may be built-in to the appliance.

Very interesting what you mention in these paragraphs. So in this case a
measurement on the battery would have to give a voltage between 3.0V and
4.1V per cell if the battery works correctly?

>>>> But in any case, in all this time, whenever the battery was
>>>> charged, the charge level was up to 100%. So just since yesterday
>>>> I suddenly saw that the load stayed at 38% and I started to
>>>> experience this issue.  

>>> That makes me think of a component failure. Likely the battery, but
>>> conceivably something in the laptop.

> Yes. The problem is that it's not possible to rig up a quick charging
> test for lithium, or a dummy battery load to check the charger. With
> other technologies, a current source powered from a higher voltage,
> with a voltmeter, would give some idea of the battery state. 

Do you think the problem might be in the charger? At the beginning I had
thought that maybe not since the notebook works when it is connected.
Although perhaps it could be that if the electronics that manages the
phases that you mentioned before is physically in the charger, the
problem is in the charger.

>> Perhaps the ultimate test is going to a business where they have
>> original Lenovo components, ask them for a new battery to test it at
>> the moment with the notebook and, if all goes well, then buy it.

> Sadly, that's the only real test.

Earlier I telephoned the supplier where I bought this battery and he
offered to test (without cost) my notebook with a new battery for a full
charge cycle to make sure the problem was in the battery.

> Something worth trying if you have access to a voltmeter: the battery
> pack will have at least three terminals, maybe more, and a voltage
> should be measurable across two of them. The voltage value may show a
> missing (shorted) cell. Discharged as far as possible, a lithium cell
> should be around 3.0V, and fully charged, 4.2V. The battery should be
> marked as to how many cells it contains. If you get a reading of less
> than 3.0V per cell, there is almost certainly a dead cell. Probably you
> won't get a conclusive reading, if the charger thinks there's 38%
> charge, then the volts per cell is probably higher than 3.0, which it
> can be if one cell is missing but the others are well-charged.

I have a multimeter, so I could try that. This is a 6 cell battery. Here
[1] are the specifications of Lenovo in case this is useful.


Thanks for your reply.

Kind regards,
Daniel

[1] https://support.lenovo.com/ar/en/solutions/pd024285

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#179489

On Mon, 27 Mar 2017 14:54:25 -0300
Daniel Bareiro <daniel-listas@gmx.net> wrote:

> Hi, Joe.
> 
> >>>> Checking the purchase invoices, I bought the notebook on
> >>>> September 19, 2013, and then changed the battery on November 2,
> >>>> 2015. So less than two years ago I have this battery.
> >>>>
> >>>> The notebook I use it practically every day and I leave it
> >>>> sleeping from one day to the next so I do not have to open every
> >>>> application every time. I'm not sure if that impacts so much on
> >>>> the battery life.    
> 
> >>> If it was a long term degradation, possibly. With some battery
> >>> technology/technologies(?) there is a "memory" effect. If there
> >>> is a repeated "shallow discharge"/recharge cycle ( sleep overnight
> >>> followed by running during day with charger plugged in) the
> >>> effective battery capacity will decrease. IIRC that applies to
> >>> only one technology but can't remember which.    
> 
> >> I remember that when I bought this battery, I was advised to leave
> >> the charger plugged in for a little more than an hour after the
> >> charging level reaches 100%. And for the subsequent times, try to
> >> avoid having the charger plugged in when the battery charge level
> >> reaches 100%. So I was following that criteria. What do you think
> >> about that?  
> 
> > I would hesitate to contradict a supplier, but a lithium battery
> > charger should not permit overcharging. It *must* not, as there is a
> > serious risk of fire or explosion, not just a reduction of life as
> > will occur with other types. The maximum charge voltage must be a
> > fairly precise 4.20V per cell, and really the only practical way to
> > charge these batteries is to use one of many specialised integrated
> > circuits designed to do just that.  
> 
> I think he made that recommendation about disconnecting the charger
> when the charge reaches 100% because he thought otherwise would
> affect the battery life.

As I say, it shouldn't. Lithium chargers don't provide a continuous
trickle charge. Various sources on the Net claim that life will be
longer if you never fully-charge the battery, but with a laptop, you're
always going to be looking for maximum running time. Supposedly it's
best to store the battery for long periods half-charged, but then
whenever you need to use the laptop, you have about an hour to wait for
full charge. You can't win.
> 

> 
> Very interesting what you mention in these paragraphs. So in this
> case a measurement on the battery would have to give a voltage
> between 3.0V and 4.1V per cell if the battery works correctly?

Pretty much. The discharge protection should come in about 3V, but
might allow discharge a bit further. There is little energy left in the
cell at 3V. Here's a set of discharge curves at various currents:

http://www.richtek.com/battery-management/img/battery-discharge.png

> 
> >>>> But in any case, in all this time, whenever the battery was
> >>>> charged, the charge level was up to 100%. So just since yesterday
> >>>> I suddenly saw that the load stayed at 38% and I started to
> >>>> experience this issue.    
> 
> >>> That makes me think of a component failure. Likely the battery,
> >>> but conceivably something in the laptop.  
> 
> > Yes. The problem is that it's not possible to rig up a quick
> > charging test for lithium, or a dummy battery load to check the
> > charger. With other technologies, a current source powered from a
> > higher voltage, with a voltmeter, would give some idea of the
> > battery state.   
> 
> Do you think the problem might be in the charger?

Yes, certainly. That's why I said it's difficult to know what's going
on without either a known good battery or a known good charger. You'd
better hope it's the battery, as that is easy to fix...

> At the beginning I
> had thought that maybe not since the notebook works when it is
> connected. Although perhaps it could be that if the electronics that
> manages the phases that you mentioned before is physically in the
> charger, the problem is in the charger.

The external power for the laptop is separate from the charger
electronics. The charger must supply a defined current, and if some of
this were diverted to run the laptop, it would be difficult for the
charger to monitor the state of the battery. So the external power is
supplied to two paths, to the laptop electronics and to the charger,
with laptop power being taken from the battery when the external power
is not present.

> 
> >> Perhaps the ultimate test is going to a business where they have
> >> original Lenovo components, ask them for a new battery to test it
> >> at the moment with the notebook and, if all goes well, then buy
> >> it.  
> 
> > Sadly, that's the only real test.  
> 
> Earlier I telephoned the supplier where I bought this battery and he
> offered to test (without cost) my notebook with a new battery for a
> full charge cycle to make sure the problem was in the battery.

You are lucky. Many suppliers have neither the equipment nor the
willingness to help after the warranty period.
> 
> > Something worth trying if you have access to a voltmeter: the
> > battery pack will have at least three terminals, maybe more, and a
> > voltage should be measurable across two of them. The voltage value
> > may show a missing (shorted) cell. Discharged as far as possible, a
> > lithium cell should be around 3.0V, and fully charged, 4.2V. The
> > battery should be marked as to how many cells it contains. If you
> > get a reading of less than 3.0V per cell, there is almost certainly
> > a dead cell. Probably you won't get a conclusive reading, if the
> > charger thinks there's 38% charge, then the volts per cell is
> > probably higher than 3.0, which it can be if one cell is missing
> > but the others are well-charged.  
> 
> I have a multimeter, so I could try that. This is a 6 cell battery.
> Here [1] are the specifications of Lenovo in case this is useful.
> 

So you're looking for 18V or more. But five well-charged cells will
give you 20V...

-- 
Joe

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