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After checking two HP Laptops, one relatively new, only 2 months old and the battery is less than a week old. The other one is about a year old. both have the same issue. The laptop's battery charges up to a certain percentage and then stops right there.

Here is an image of what I see when checking the charge:

enter image description here

The way I read this is that the Total Battery Energy by design is 88.8Wh. After 12 hours charging (after discharging the battery completely to recalibrate) it gets to 34.1Wh and stays there. Only 38.4% of the 100% battery charging level.

The other laptop does the same but up to 32.1%.

Here is another pic with the /proc info:

enter image description here

And yet another one with the acpi -V command:

enter image description here

I checked if the connection was grounded. I checked that the cable connected to the laptop was good, even checked with a tester the current, voltage, etc.. Somehow is not charging completely or not showing the correct percent.

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up vote 0 down vote accepted

I have seen that happen on old, almost-dead batteries. I have also seen that happen when the power supply on the laptop failed. On my 18-month old Dell, acpi -V returns "last full capacity = 87%".

Are the 2 laptops the exact same model? Perhaps it's an incompatibility between the laptop model and the battery. Do you have access to a different laptop model that uses the same battery?

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After careful checking, the battery was sold as new but was an old one. – Luis Alvarado Aug 28 '12 at 2:10

You should try recalibrating it; discharge first to the auto-shutdown/hibernate point (~5%), not to 0%. Does it charge with earlier Ubuntu versions? If so, that may indicate a problem with Ubuntu.

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Already mentioned in the question that I did a recalibration with both. – Luis Alvarado Aug 10 '12 at 16:22

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