odd charging problem with BQ E4.5 OTA-3 r3



  • I have an odd charging problem with the above device. It charges fine with the normal charger provided by BQ, but it seems to have a problem with some USB charger gadget, build by my own 10 years ago and used all the time with my E4.5 running the Canonical UT versions.

    The charger is the so called 'minty boost', see here:
    https://learn.adafruit.com/minty-boost?view=all

    When this is used for charging, the device says it is charging, but does not do so. Here are the details:

    Without the charger connected the ..../battery/ file says:

    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ ls -l
    total 0
    -r--r--r-- 1 root root 4096 Oct 13 09:42 BatteryAverageCurrent
    -r--r--r-- 1 root root 4096 Oct 13 09:42 BatterySenseVoltage
    -r--r--r-- 1 root root 4096 Oct 13 09:42 batt_temp
    -r--r--r-- 1 root root 4096 Oct 13 09:42 batt_vol
    -r--r--r-- 1 root root 4096 Oct 12 19:51 capacity
    -r--r--r-- 1 root root 4096 Oct 12 19:51 capacity_2nd
    -r--r--r-- 1 root root 4096 Oct 13 09:42 ChargerVoltage
    lrwxrwxrwx 1 root root    0 Oct 13 09:42 device -> ../../../battery
    -r--r--r-- 1 root root 4096 Oct 12 19:51 health
    -r--r--r-- 1 root root 4096 Oct 13 09:42 InstatVolt
    -r--r--r-- 1 root root 4096 Oct 13 09:42 ISenseVoltage
    drwxr-xr-x 2 root root    0 Oct 13 09:42 power
    -r--r--r-- 1 root root 4096 Oct 12 19:51 present
    -r--r--r-- 1 root root 4096 Oct 12 19:51 present_2nd
    -r--r--r-- 1 root root 4096 Oct 12 19:51 status
    -r--r--r-- 1 root root 4096 Oct 12 19:51 status_2nd
    lrwxrwxrwx 1 root root    0 Oct 13 09:42 subsystem -> ../../../../../class/power_supply
    -r--r--r-- 1 root root 4096 Oct 12 19:51 technology
    -r--r--r-- 1 root root 4096 Oct 12 19:51 temp
    -r--r--r-- 1 root root 4096 Oct 13 09:42 TempBattVoltage
    -r--r--r-- 1 root root 4096 Oct 13 09:42 TemperatureR
    -r--r--r-- 1 root root 4096 Oct 13 09:42 type
    -rw-r--r-- 1 root root 4096 Oct 12 19:52 uevent
    -r--r--r-- 1 root root 4096 Oct 12 19:51 voltage_max_design
    -r--r--r-- 1 root root 4096 Oct 12 19:51 voltage_now
    
    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ grep '.' capacity*
    capacity:90
    capacity_2nd:50
    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ grep a stat*
    status:Discharging
    status_2nd:Discharging
    

    Why there are two files, status and status_2nd, and capacity and capacity_2nd? This was not with Canonicals versions.

    When I now plug-in the minty boost charger it shows that it is charging:

    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ grep a stat*
    status:Charging
    status_2nd:Discharging
    

    and on the display too:

    • battery symbol in the bar on top turns green
    • battery screen shows: Charging now and Charge level 90%

    But the battery level is going down:

    10 minutes later:

    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ grep a stat*
    status:Charging
    status_2nd:Discharging
    phablet@ubuntu-phablet:/sys/devices/platform/battery/power_supply/battery$ grep '.' capacity*
    capacity:86
    capacity_2nd:50
    

    Why is this?

    When I use the same charger and same cable with another E4.5, still running the latest Canonical OTA, it works fine.



  • Is there some developer forum / channel where I could bring this up?



  • One year later and now with OTA-11 installed ...

    I bought a so called USB power meter and run the test below. In summary the ALTOIDS with two AA batteries of 2700mAh each charges the BQ E4.5 to nearly 40%:

    
    LogiLink PA0067
    https://www.reichelt.de/usb-messgeraet-5-v-4000-ma-usb-logilink-pa0067-p145269.html
    
    charging test with ALTOIDS "powerbank"
    
    time   LogiLink         BQ E4.5 battery display
    14:45  4.55V / 0.12A    44% ALTOIDS connected
    14:50  4.58V / 0.19A    49%
    14:55  4.59V / 0.21A    50%
    15:10  4.62V / 0.27A    57%
    15:15  4.62V / 0.30A    60%
    15:20  4.62V / 0.29A    63%
    15:25  4.63V / 0.31A    65%
    15:30  4.63V / 0.32A    67%
    15:35  4.64V / 0.32A    68%
    15:40  4.63V / 0.32A    70%
    15:45  4.63V / 0.32A    71%
    
    ~ 1h * 4.6 * 0.3 = 1380mAh
    
    15:50  4.63V / 0.32A    72%
    15:55  4.63V / 0.31A    73%
    16:00  4.63V / 0.31A    74% ALTOIDS disconnected
    
    (break)
    
    18:20  4.60V / 0.25A    41% ALTOIDS reconnected
    18:25  4.57V / 0.20A    45%
    18:30  4.56V / 0.17A    47%
    18:35  4.56V / 0.14A    49%
    18:40  4.54V / 0.09A    50%
    18:45  4.54V / 0.07A    50%
    18:48  4.52V / 0.00A    50%
    
    ~ 0.5h * 4.55 * 0.15 = 340mAh
    


  • This sounds like a problem with the charger code which is normally the same like in Android. We do not in any way influence this, we just read the stats and display them. Charging is coupled with a kernel driver that does all the magic.

    Since BQ devices do not have an opensourced tree its very hard to even analyze the issue. You could however see if there are any log entries in dmesg that look suspicious when you connect / disconnect the charger.

    My girlfriend has an E 4.5 since 3 years or so and its charging pretty well. So I suspect rather a hardware problem, but of course idk...

    BR



  • @Flohack
    I had fun with my m10 fhd , a long time ago, it would not charge off , my old Samsung chargers, but was ok on it's own BQ charger
    ( Originaly Ubuntu device).


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