You should not leave your laptop plugged in charging to 100%. The commonly used value for being constantly plugged in is 80%. Lenovo and Dell both recommend this. I use the Battery Threshold system on my two Lenovo laptops and they stay plugged in and use a maximum of 80%
Battery Health on my X1 is excellent (battery is 16 months old). Battery Health on my X230 is about half (battery is 4 years old).
All batteries wear out from age more than from the charging threshold used. Try the steps to recalibrate your battery and see if it works normally. Possibly it needs to be replaced.
You need to do two things:
1. Reset (recalibrate) the battery. Hopefully this step will cause your battery to show correct readings.
https://www.ultrabookreview.com/20942-calibrate-laptops-battery-fix-inaccurate-wear-info/
Here is a summary of the steps:
Step 1: First, you will need to let your laptop charge to its “full”
capacity. OEMs like Dell and Lenovo allow the user to set
charging-thresholds on the battery in order to preserve the battery
health (this is a very good practice that I encourage all OEMs to
follow). Thus, to charge the laptop fully, you’ll need to find that
setting and set your charging threshold temporarily to 100%. On XPS
machines, this is done through Dell Power Manager or the BIOS.
You’ll need to set the charging behavior to “Standard” or change the
slider manually to 100% to complete the first step. Once this is done,
make sure your laptop is plugged-in and allow it to charge completely.
Step 2: Next, you need to let the battery completely discharge until
forced shut-off (not just hibernation). There are a few ways to do
this, but my favourite method is the simplest: Restart the laptop in
BIOS mode, then go out of the house for the day. With this method, you
don’t need to worry about the laptop going to sleep or hibernating as
these features are not enabled when viewing the BIOS. Additionally,
power-saving states are not enabled for the CPU when in the BIOS
either, meaning the laptop will run down significantly faster than it
would in Windows under normal usage.
You could also use the laptop normally and let it run down until it
automatically hibernates, then leave it in BIOS as described above as
well. This requires your turn off all of the sleep and hibernation
timers in the Power Options control panel first, however.
Step 3: WAIT. Do not immediately charge the laptop; be sure the laptop
has been sitting cool and unplugged for 3-5 hours before the next
step. Failing to perform this step can result in making your reported
battery wear worse.
Step 4: Plug the laptop in and let it charge to maximum uninterrupted.
You should be able to use the laptop in Windows at this point, but I
let it charge in BIOS out of superstition. When you generate your
battery report again, you should (hopefully) see a much higher rated
capacity for your new battery.
Conclusion That’s it! Using this method I was able to reduce my 9575
reporting 14% wear down to 4%, my 9570 reporting 10% down to 3.8%, and
my 9370 reporting 8% wear down to 4%, and I hope it fixes the problem
for you simply as well. As always, try to practice good battery care
to prolong their lives: Keep them cool, don’t run them dry, and don’t
charge them to maximum often. If you are interested in reading more
about safety and care for Li-Ion batteries, you can check out this
guide for further reading.
2. Set the threshold to 80%
Method to set threshold
Go to the Battery Setting page, and then click Custom. Under Start
Charging, move the slider to the percentage threshold at which the
battery begins charging, or enter a number in the text box. For
example, entering 60 causes the battery to start charging when it
depletes to 60 percent of the total available charge. Under Stop
Charging, move the slider to the percentage threshold at which the
battery stops charging, or enter a number in the text box.
Enter 80 in this box to set the Threshold to 80%
This setting allows you to run the laptop plugged in all the time.
