Laptop battery and Linux

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Any idea how to get a netbook battery to re-calibrate? I have an Acer Aspire One A0532h. It was given to me to "dispose" of it, so I wiped the Win7 that was on it and put Linux Mint on. The old battery was quite tired so I bought a replacement. Trouble is, it seems to be stuck thinking it has lots more life than I can get out of it. Once it gets to about 54%, it just stops dead and won't power up until I plug it in. Unfortunately, after a couple rounds of this it hasn't changed its predicted life at all. The BIOS has no utility to calibrate the battery. Google even pointed me to something called power-calibrate, but when I ran it it reports the hardware isn't compatible.
 
Update to the latest BIOS (1.26) first if it doesn't have it already. Looks like since Windows is out, you'll need to do it in DOS so I guess creating a bootable thumbdrive in Rufus or similar would be in order.
 
Typically when you see this behaviour the battery is pretty worn and nearing its useful life.

That being said, and without knowing specifics of the "fuel gauge" in this example, the general procedure to re-calibrate the fuel gauge is:

1. Plug the charger and let it reach 100%, then let it stay at 100% for a few hours. It's important not to unplug during this time but you can use the laptop normally during this time.

2. Remove the charger and let the battery discharge to zero through normal use. Do not re-plug the charger at any time, but it's OK to shutdown the laptop during the discharge phase.
=> Note: Since the OS may shutdown before it reaches 0%, you can boot into BIOS and let it discharge the remaining amount until it shuts off due to no remaining battery capacity. Also, it's recommended to reduce the load, such as using low screen brightness, when you reach the end of the discharge cycle. A high discharge current on a weak battery will lead to an earlier shutdown.

3. Let the battery "rest" in this fully discharged state for a few hours before you plug in the charger. I usually let it sit in this state overnight then let it charge back to 100%. It may be needed to repeat the cycle a few times, but take note that each full charge/discharge cycle further wears the battery.

Here's the science behind it: The fuel gauge typically has a small microprocessor that monitors the battery during charging and discharging cycles in order to predict the capacity. As the battery ages and/or if there are not sufficient discharge cycles (20-100%), it can lose calibration leading to sudden shutdowns at seemingly high states of charge (battery %). Even though the battery is at 0% and the system won't turn on, there is usually enough energy in the battery to power the fuel gauge which allows it to re-calibrate at the 0% level. It will then relearn the low and the high capacity states.

This procedure works for most Apple and Dell products, but may vary depending on the battery manufacturer.
 
Last edited:
Originally Posted by WagonWheel
This procedure works for most Apple and Dell products, but may vary depending on the battery manufacturer.

Yeap, battery calibration is mostly independent of the OS on the machine. The BIOS is what really keeps track. While Windows may have the ability to bypass the BIOS and 'read' the battery capabilities directly, you can still teach it using steps like you gave.
 
A different take- " I bought a replacement " battery. Was this a rebuilt or aftermarket battery ? I have had poor results with aftermarket and rebuilt batteries. I can understand in the case of aftermarket- they cut corners and do not put in the electronic controls like the OEM battery. In some cases the OEM puts in controls into the battery that discourage the aftermarket. For rebuilt batteries though- all they are doing is replacing the cells in an OEM battery, so this should come out fine right ? But in my experience I am 0 for 2 getting rebuilt batteries, but I have not tried in over 5 years. At one point I saw some software that was supposed to assist in recalibrating batteries, but it was only sold to professionals and was very costly (like many thousands of $$).
 
Linux power calibration from the terminal.

sudo apt install power-calibrate

Then type
power-calibrate -r
 
As far as I know it was new battery, but maybe it was a refurb. The netbook had Windows 7 starter edition on it originally according to the tag, and I managed to download the ISO for it. I'll have to say, I'm a little disappointed by PeppermintOS (which I had tried first) and Mint. I didn't think it would be a screamer by any stretch with a no-frills video, but it was very jerky watching any kind of video. Put Win 7 back on it, got the key to work, and it's much better under Windows. We'll see if it works any kind of magic on getting the battery to be any more accurate.

Anybody know if the Win10 media creation tool mentioned at the top of the form works for Win 7 starter edition? Even if I don't keep Windows I can at least run the BIOS update now.
 
a lot of aftermarket batteries lie about their capacity.
a dead giveaway is say a 5200mah pack that showed wear level of 70% after 1 cycle.
the cheap pack had all the id and capacity calibration for a genuine pack but instead of the 2600mah cells it should have been built with it had 1800mah cells.
this is a common fraud with cheap packs on ebay and amazon.
https://www.nirsoft.net/utils/battery_information_view.html
 
Originally Posted by kc8adu
a lot of aftermarket batteries lie about their capacity.
a dead giveaway is say a 5200mah pack that showed wear level of 70% after 1 cycle.
the cheap pack had all the id and capacity calibration for a genuine pack but instead of the 2600mah cells it should have been built with it had 1800mah cells.
this is a common fraud with cheap packs on ebay and amazon.
https://www.nirsoft.net/utils/battery_information_view.html


Thanks for the link, it's showing some useful info.

Things aren't much better under Windows. I'm thinking I must have a bum battery that's got problems or it's a bad refurb. Shows 4-5 hours of life, but once it gets down around 50% it just dies with no warning. I can let it sit for a couple hours to let the battery cool and rest, but pushing the power button it's definitely not turning on. Once i plug it in and boot up, it still reports it's at 50% capacity and charging, but if I pull the plug it will run for a very short time and shut off. It seems to be incapable of calibrating itself.

This utility actually reports only about 50 minutes of capacity, but the percentage agrees with the battery tray.
 
Wild West of Linux and especially laptops! When it works it is incredible and elegant otherwise the time sink of figuring out drivers and tweaks takes a special person.
 
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