How to get the correct battery status?

Question

At this moment, ever since I installed Ubuntu on this machine, the battery status says: not present.

Looking at this answer, however, I find that /proc/acpi/battery/BAT1/info (sometimes its /proc/acpi/battery/BAT0/info, use tab complete to help) has the following info:

present: yes
design capacity: 4400 mAh
last full capacity: 4400 mAh
battery technology: rechargeable
design voltage: 11100 mV
design capacity warning: 300 mAh
design capacity low: 132 mAh
cycle count: 0
capacity granularity 1: 32 mAh
capacity granularity 2: 32 mAh
model number: BAT1      
serial number: 11        
battery type: 11        
OEM info: 11        

In accordance to this answer, I've checked the /proc/acpi/battery/BAT1/state file:

present:                 yes
capacity state:          ok
charging state:          charged
present rate:            unknown
remaining capacity:      unknown
present voltage:         10000 mV

The acpi -b command returns:

Battery 0: Unknown, 0%, rate information unavailable

Any suggestions on getting the battery info updated?

Solution 1

The acpi -b error you have reported most probably indicate an ACPI type issue.

ACPI is an open-standard for device and power-management.

Some laptops (most googled that I found were Acer) incorrectly report its battery details to Ubuntu. I'm not sure of your laptop type and model - nor its BIOS version.

Sometimes you need to compile your own kernel with a fixed DSDT table.

Sometimes you need to upgrade your BIOS to the very latest offered by your manufacturer.

If you decide on the latter action you should remember that updating the BIOS of a motherboard or laptop is always a risky operation, because if something goes wrong, the risk of irreparably damaging the hardware is very high.

You will need to follow the instructions for BIOS updates from your manufacturer.

Solution 2

I was able to solve this problem using fossfreedom's suggestion to update BIOS. I have an Acer Aspire TimelineX 4820T, running ubuntu 11.10. Here's what I did:

1. sudo apt-get install unetbootin
2. inserted blank flashdrive, used diskutil to format it to FAT
3. downloaded the CORRECT bios update from Acer (I typed in my serial number and used the latest bios update .exe file)
4. used unetbootin to make the USB bootable with FreeDOS
5. copied the bios .exe file to the USB drive
6. restarted and chose option "5" for FreeDos
7. switched to C: drive and ran the bios executable. (Make sure you have enough power, although this doesn't take very long)
8. removed USB drive, rebooted into Ubuntu and battery problem was solved!

Thanks go to 4zzdawg for instructions on how to update the bios!

Comments

[GUI Junkie]

Acer Aspire 5745G. Which option is easier? Compiling the kernel or updating the BIOS?

[nilsonneto]

... updating your BIOS ... what version is your BIOS? I would carefully read the release notes first because BIOS updating, if not done correctly can leave you without a working laptop.

[nilsonneto]

... I found this link - look at the ACPI on that page. That looks like good news! linlap.com/wiki/acer+aspire+5745g

[GUI Junkie]

The BIOS version is v1.11 (sudo dmidecode -s bios-version)

[nilsonneto]

the latest version on the acer website is v1.19 - I couldnt find any release notes though :(

[GUI Junkie]

I've downloaded the software and will have to create a bootable CD or flash. Will report back.

[GUI Junkie]

Finally, did the BIOS update and it works. I used rufus.exe to create the USB MS-DOS flash drive.

[nilsonneto]

sounds intriguing ... can you create a question and answer this yourself ... this could be very useful info!

[GUI Junkie]

Not sure, this is a Windows program. Look here