I normally do not use my battery, but once a month, I normally drain my battery to 12%, charge it to 100%, then drain it to around 40% before removing it and storing it.
This time it is different.
I drain the battery to 12%.
I then charge it to 100%.
I unplug the laptop and drain the battery back to 40%, but this time, it went from 90% to 50%, drains to 45%, and it jumps up to 55%. I let it drain to 50%, and it jumps up to 65% all the while the laptop is unplugged.
I then let it drain all the way down to 12%, but when it is at 13%, it jumped down to 10%, then I waited till it goes to 9%, but the laptop shuts down before it reached 9%. By shut down, I mean the kind where if you didn't have a battery in your laptop, and you pulled the AC cord out.
My laptop now thinks 0% charge is 10% charge, and at 10%, the laptop shuts down.
How do I fix this?