Battery Charged at 97%

That battery appears to be in fairly good shape for a 3 year old laptop with 87% of original capacity remaining, not "broken" at all.

Looking a bit more closely at your output:

state:               fully-charged
energy:              55,5333 Wh
energy-full:         57,1428 Wh
energy-rate:         0,0111 W

Looking at "energy rate", the battery is actually still charging, just at a very slow rate, something not uncommon when the battery is nearly full.

It appears that the battery controller just signals "fully charged" due to the very slow charge rate (also not uncommon, just a convenience for the user), e.g. it tries to tell you this:

Just go ahead and unplug the device now, because topping the battery off will take a long time.

Leave the laptop plugged in, and you will see the battery charge creep up to 100% very slowly.

My laptop does the same thing, it will show "fully charged" (and even a green LED on the charger will light up) as soon as it reaches 95%.

This makes perfect sense, since charging it from 10% to 90% takes 2 hours, from 90% to 95% takes 30 minutes, and from 95% to a full 100% can take another 1-1.5 hours.

Edit:

To answer your question in comment "it is plugged in for 24 hours already", and given the very low rate at which it charges currently, this can be a sign that the part of the battery that is still charging is about to fail, again very normal for an aged battery.

In this case, the battery controller will soon update the "energy-full" value (likely after plugging it out and restarting the device from being turned off) to the new capacity.

With your output above, you'll probably then be looking at a remaining total capacity of about 85% instead of 87% like you have now, which is still excellent for a 3 year old battery.

Last week my laptop battery was stuck at 97% charged for a few days.

Finally I got annoyed, unplugged it for 1/2 hour then plugged it back in. After awhile (wasn't paying attention) it was fully charged, the charging led (front of laptop) went out and Ubuntu reports 100% charge.

The laptop is normally 100% charged as it's always plugged in, never shutdown and simply put to sleep via lid close.

Have no idea how it got stuck at 97% in the first place, but unplugging it for 1/2 hour and letting it charge "full speed ahead" allowed it to get over that 97% speed bump.

I think it more of a BIOS issue than Ubuntu or Linux.

More anecdotal and less scientific than the preceding answer but, hey it works for me.