I did search for this problem and found many related posts but nothing exactly like what is going on with my machine. I have a Thinkpad 440p running XFCE.
My battery icon shows 83% charged. I ran a check from the terminal and this was confirmed.
Problem is, when I try to power the computer on, nothing happens, as if the battery is dead. I connect it to the charger and it boots up.
More than that, when it is connected to a power source, it shows itself to be charging but isn’t. The icon reads 83% and charging but doesn’t change at all. As soon as I disconnect the power cord…out go the lights.
My uneducated guess is that it isn’t a dead battery, but who knows. The only thing that has changed recently is I had a USB mic hooked up. Could that have drained the battery? But why isn’t the computer reading the power level properly?
My guess is that you do have a dead battery, at least in the sense that it cannot provide energy.
The non null measurement would be linked to how charge is measured…
Please read this: How to provide good information
and press the three dots … below your post and press the to give us more information so we can see what’s really going on.
Now we know the symptom of the disease, but we need some more probing to know where the origin lies…
An inxi --admin --verbosity=7 --filter --no-host --width would be the minimum required information for us to be able to help you. (Personally Identifiable Information like serial numbers and MAC addresses will be filtered out by the above command)
Also, please copy-paste that output in-between 3 backticks ``` at the beginning and end of the code/text.
The output to:
sudo tlp-stat --battery
would be helpful as well to be 100% sure.
P.S. If you want to notify me that you did provide this information, please this message and I’ll come back and have another look.
P.P.S. If you enter a bit more details in your profile, we can also see which Desktop Environment you’re using, which exact CPU/GPU or Kernel, … you have without typing it every time
Welcome to Manjaro! 
to give us more information so we can see what’s really going on.
this message and I’ll come back and have another look.