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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?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-05-24 15:10 +0200
                        Re: Issue with notebook (maybe the battery?) Fungi4All <fungilife@protonmail.com> - 2017-05-24 17:20 +0200
                          Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-05-25 03:00 +0200
                        Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-05-25 02:30 +0200
                          Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-05-25 03:00 +0200
                            Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-05-25 03:30 +0200
                              Re: Issue with notebook (maybe the battery?) Daniel Bareiro <daniel-listas@gmx.net> - 2017-05-28 03:00 +0200
                                Re: Issue with notebook (maybe the battery?) David Wright <deblis@lionunicorn.co.uk> - 2017-06-02 21:40 +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

Page 2 of 2 — ← Prev page 1 [2]

#181357

On Wed 24 May 2017 at 21:50:20 (-0300), Daniel Bareiro wrote:

> When you talk about "the numbers", do you mean to see by the console the
> values that are obtained for both batteries (voltage, for example) to
> make a comparison?

Yes, the bash function I use is:

battery () 
{ 
    local BATTERYFILE="/sys/class/power_supply/BAT0/uevent";
    [ ! -r $BATTERYFILE ] && printf '%s\n' "$BATTERYFILE not found!" && return 1;
    date +%Y-%m-%d-%H-%M-%S;
    cat $BATTERYFILE;
    local FILEBATNOW="/sys/class/power_supply/BAT0/charge_now";
    local FILEBATPREV="/sys/class/power_supply/BAT0/charge_full";
    local CHARGE=$(( 100 * $(< $FILEBATNOW) / $(< $FILEBATPREV) ));
    [ $CHARGE -lt 100 ] && printf '%s\n' "Charge: $CHARGE%"
}

AIUI uevent gives you the lot, which varies by model etc.
so just   cat /sys/class/power_supply/BAT0/uevent
should do it, with and without the power supply connected.

(I run a slightly more sophisticated version that also
reads the CPU temperature, has error trapping, and changes
the root window colour according to battery state and,
if frying, temperature.)

Cheers,
David.

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#181528

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Hi, David.

On 24/05/17 22:23, David Wright wrote:

>> When you talk about "the numbers", do you mean to see by the console the
>> values that are obtained for both batteries (voltage, for example) to
>> make a comparison?

> Yes, the bash function I use is:
> 
> battery () 
> { 
>     local BATTERYFILE="/sys/class/power_supply/BAT0/uevent";
>     [ ! -r $BATTERYFILE ] && printf '%s\n' "$BATTERYFILE not found!" && return 1;
>     date +%Y-%m-%d-%H-%M-%S;
>     cat $BATTERYFILE;
>     local FILEBATNOW="/sys/class/power_supply/BAT0/charge_now";
>     local FILEBATPREV="/sys/class/power_supply/BAT0/charge_full";
>     local CHARGE=$(( 100 * $(< $FILEBATNOW) / $(< $FILEBATPREV) ));
>     [ $CHARGE -lt 100 ] && printf '%s\n' "Charge: $CHARGE%"
> }

Interesting... thanks for sharing :-)

I had to modify it because in my case I don't have "BAT0/charge_full"
and "BAT0/charge_now". I have "BAT0/energy_now" and "BAT0/energy_full".
Maybe you're using Stretch or a Backports kernel?

> AIUI uevent gives you the lot, which varies by model etc.
> so just   cat /sys/class/power_supply/BAT0/uevent
> should do it, with and without the power supply connected.

Sending the values to a file, I then graphed them using GNUPlot. A
picture tells more than thousands of words :-) It is interesting to see
how the charging curve describes almost a perfect straight line
and then begins to decelerate as it approaches 100%.

https://ibin.co/3Ny1TPsm9oNn.png

> (I run a slightly more sophisticated version that also
> reads the CPU temperature, has error trapping, and changes
> the root window colour according to battery state and,
> if frying, temperature.)

It would be interesting to see it :-)


Kind regards,
Daniel

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#181705

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On Sat 27 May 2017 at 21:55:06 (-0300), Daniel Bareiro wrote:
> Hi, David.
> 
> On 24/05/17 22:23, David Wright wrote:
> 
> >> When you talk about "the numbers", do you mean to see by the console the
> >> values that are obtained for both batteries (voltage, for example) to
> >> make a comparison?
> 
> > Yes, the bash function I use is:
> > 
> > battery () 
> > { 
> >     local BATTERYFILE="/sys/class/power_supply/BAT0/uevent";
> >     [ ! -r $BATTERYFILE ] && printf '%s\n' "$BATTERYFILE not found!" && return 1;
> >     date +%Y-%m-%d-%H-%M-%S;
> >     cat $BATTERYFILE;
> >     local FILEBATNOW="/sys/class/power_supply/BAT0/charge_now";
> >     local FILEBATPREV="/sys/class/power_supply/BAT0/charge_full";
> >     local CHARGE=$(( 100 * $(< $FILEBATNOW) / $(< $FILEBATPREV) ));
> >     [ $CHARGE -lt 100 ] && printf '%s\n' "Charge: $CHARGE%"
> > }
> 
> Interesting... thanks for sharing :-)
> 
> I had to modify it because in my case I don't have "BAT0/charge_full"
> and "BAT0/charge_now". I have "BAT0/energy_now" and "BAT0/energy_full".
> Maybe you're using Stretch or a Backports kernel?

I get the same filenames on my systems with wheezy, jessie, and the
latter using a backported 4.9 kernel. But I've never investigated
where these decisions are made. Similarly it's a mystery to me why
wheezy gives one laptop two sound controls, whereas jessie gives
it five.

> > (I run a slightly more sophisticated version that also
> > reads the CPU temperature, has error trapping, and changes
> > the root window colour according to battery state and,
> > if frying, temperature.)
> 
> It would be interesting to see it :-)

Sure. Feel free to modify it to your taste. The laptop I wrote it
for has one critical temperature point (99), hence the two headroom
values which are arbitrary. The first would be reached at such
times as playing videos, so it warned me in case it was lying
on a soft surface, which interferes with its ventilation.

This laptop, which is older, appears to be more sophisticated,
having four trip point temperatures, and also a battery temperature.
But it doesn't overheat so I've never bothered to modify the code.

The charge colours are more useful most of the time, especially
when the batteries are as old as these are.

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

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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

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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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#179540

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

Hi, Joe.

On 27/03/17 16:01, Joe wrote:

>>>> 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.

Thank you for these observations.

>> 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

Thanks for the clarification.

>>> 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...

But in any case, whether the problem is in the charger or the battery, I
suppose that to solve the issue I will have to change the part. I
suppose if the problem is in the charger, the cost will be less compared
to a battery.

>> 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.

If I understood correctly, I think that here you was suggested that it
could also be a problem related to another internal component of the
notebook that diverts power from the charger to the battery for its charge.

>>>> 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.

Yes, it is good that they have had that good predisposition. In fact,
when I talked to them on the phone, I told them that if I saw that when
I plugged in the charger, the charge led behaves correctly, I could
assume the issue was on the battery and that would make the test a
little quick. But the person I spoke insisted on doing a full load cycle
so they would be reassured that everything works fine. Going there and
back takes me at least three hours (plus the the time awaiting for full
charge of the battery) so the trip would be a pain (not to mention go to
leave the notebook for the test, go back, and go later for it). The
alternative is that while the battery is charging, I stay there using
the notebook to take advantage of the time :-)

>>> 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...

This is very weird. I do not had any reading. The slots of the contacts
are very thin (attached image) and I tried placing the probes
horizontally, vertically and trying several combinations leaving one
probe fixed and changing the position of the other, but without
differences. I tried with the scale of 20V and then with the next one,
but I did not have readings in any case. In fact later, to test the
operation of the multimeter, I measured the charge of an old 9V battery
and got a reading of 2.10V, so I do not think it's a problem with the
multimeter.

https://ibin.co/3H7uKkzIf4Ui.jpg


Thanks for your reply.

Kind regards,
Daniel

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#179543 — [OT] Re: Issue with notebook (maybe the battery?)

On Tue, 28 Mar 2017 14:14:15 -0300
Daniel Bareiro <daniel-listas@gmx.net> wrote:

> Hi, Joe.
> 

> 
> >> 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...  
> 
> But in any case, whether the problem is in the charger or the
> battery, I suppose that to solve the issue I will have to change the
> part. I suppose if the problem is in the charger, the cost will be
> less compared to a battery.

Yes, but it is unlikely that a schematic diagram of the laptop
motherboard will be available. It shouldn't be too hard to locate the
parts used in charging, but if the main IC is faulty, it may not be
available in your part of the world. Less of a problem these days, as
many Chinese parts can be sourced directly, but some years ago, my son
blew up an electronic switch on a MB by seating a memory PCB badly. I
could identify the IC, but was unable to find anyone, anywhere in
Europe, selling it. Finally, you need someone happy to make repairs on
a laptop motherboard. It may not work out cheaper than the battery.


> 
> >> 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.  
> 
> If I understood correctly, I think that here you was suggested that it
> could also be a problem related to another internal component of the
> notebook that diverts power from the charger to the battery for its
> charge.

Just that supplying power to the laptop and supplying charge to the
battery are likely to be separate functions, and if one works, that
proves nothing about whether the other works.



> 
> This is very weird. I do not had any reading. The slots of the
> contacts are very thin (attached image) and I tried placing the probes
> horizontally, vertically and trying several combinations leaving one
> probe fixed and changing the position of the other, but without
> differences. I tried with the scale of 20V and then with the next one,
> but I did not have readings in any case. In fact later, to test the
> operation of the multimeter, I measured the charge of an old 9V
> battery and got a reading of 2.10V, so I do not think it's a problem
> with the multimeter.
> 
> https://ibin.co/3H7uKkzIf4Ui.jpg
> 
Lots of contacts. It is possible that the battery electronics can tell
if it is correctly seated in the right model laptop, and will not supply
power if that is not the case. For your safety, of course.

-- 
Joe

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#179552 — Re: [OT] Re: Issue with notebook (maybe the battery?)

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

On Tue, Mar 28, 2017 at 06:47:58PM +0100, Joe wrote:
> On Tue, 28 Mar 2017 14:14:15 -0300
> Daniel Bareiro <daniel-listas@gmx.net> wrote:
> 
> > Hi, Joe.
> > 
> 
> > 
> > >> 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...  
> > 
> > But in any case, whether the problem is in the charger or the
> > battery, I suppose that to solve the issue I will have to change the
> > part. I suppose if the problem is in the charger, the cost will be
> > less compared to a battery.
> 
> Yes, but it is unlikely that a schematic diagram of the laptop
> motherboard will be available. It shouldn't be too hard to locate the
> parts used in charging, but if the main IC is faulty, it may not be
> available in your part of the world [...]

It's worth stressing on this point, since I've the suspicion that there
is a misunderstanding on your part, Daniel: the charge controller isn't
that external brick: that is probably just a more or less dumb power
source. The charge controller is buried somewhere in your laptop (as
Joe puts it, on the laptop's motherboard).

Regards
- -- tomás
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#179613 — Re: [OT] Re: Issue with notebook (maybe the battery?)

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

Hi, Joe an Tomás.

>>>>> 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...  

>>> But in any case, whether the problem is in the charger or the
>>> battery, I suppose that to solve the issue I will have to change the
>>> part. I suppose if the problem is in the charger, the cost will be
>>> less compared to a battery.

>> Yes, but it is unlikely that a schematic diagram of the laptop
>> motherboard will be available. It shouldn't be too hard to locate the
>> parts used in charging, but if the main IC is faulty, it may not be
>> available in your part of the world [...]

> It's worth stressing on this point, since I've the suspicion that there
> is a misunderstanding on your part, Daniel: the charge controller isn't
> that external brick: that is probably just a more or less dumb power
> source. The charge controller is buried somewhere in your laptop (as
> Joe puts it, on the laptop's motherboard).

Yes, now that he talked about the schematic of the motherboard, I see
that he was referring to some internal component of the notebook. Thanks
for pointing this out, Tomás :-)

And about that:

> > Lots of contacts. It is possible that the battery electronics can
> > tell if it is correctly seated in the right model laptop, and will
> > not supply power if that is not the case. For your safety, of
> > course.

It could be a possibility...

Next week I'll take the notebook to the supplier for the test with a new
battery. They offered doing tests with a new battery for an entire day.
I think I'm going to suggest them to use a liveCD as System Rescue CD or
something like that, since the disk is encrypted. Although I'm not sure
if they will feel comfortable using GNU/Linux (and I don't know if there
is liveCD's with Windows).


Kind regards,
Daniel

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#179619 — Re: [OT] Re: Issue with notebook (maybe the battery?)

Daniel Bareiro:
> Next week I'll take the notebook to the supplier for the test with a new
> battery. They offered doing tests with a new battery for an entire day.
> I think I'm going to suggest them to use a liveCD as System Rescue CD or
> something like that, since the disk is encrypted. Although I'm not sure
> if they will feel comfortable using GNU/Linux (and I don't know if there
> is liveCD's with Windows).

There is the installation disk that would boot up, I haven't tried this
madness of installing windows on a thumbstick, I have managed to install
full systems on them.

If your hd needs to be encrypted I wouldn't trust it on anyone and walk
away from it.  Eventually if it is copied out it may get decrypted given
sufficient time and resources.  It is pretty simple to take a HD out and
a service dept. know how to deal with a laptop without a hd.
So don't hand them out your data if you don't care to share them.

> Kind regards,
> Daniel

Simple electrical tests, like voltage measured on contacts can tell you
whether the battery holds charge and whether the charge circuit goes on
or not.  In 90% of the time it is a failing battery.

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#179421

> Maybe it's a problem with the battery?

Sounds very much like it.
Try another battery in the same laptop (or the same battery in another
laptop) to confirm.


        Stefan

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