Your Dashboard is showing the same thing. Mine shows Normal, even after clicking on the Battery icon doing a "Run battery check". Somehow this indicator needs to be cleared. Have you tried the "Run battery check"? Its a long shot but maybe uninstalling the HP Support Assistant and reinstalling might fix it.
36 WHr is 75% of the original capacity, after calibration that 36 WHr should be 100% of the current capacity.
So, yes it needs calibration, and indeed that is what it says.
"I keep the computer plugged in all the time, "
You have to unplug the AC adapter to calibrate the battery.
Basically to calibrate it you run down the battery to a low level. Then fully recharge it.
The point of doing this is to ensure that when the Laptop goes in to Sleep/Hibernation at a certain level lets say 5% or 10% (part of the power plan) there is still power left.
If it is not calibrated then the battery is empty before the sleep/hibernation, or it stops working at say 25% capacity. The capacity indicator is not accurate.
Capacity will gradually reduce over the years. Calibration does not increase the life of a battery.
So you need to calibrate maybe once/twice a year.
This is from HP, they use HP diagnostics to run down the battery, probably to avoid modding Windows power plans, however obviously you can think of your own method to run the battery down.
Calibrate the Battery on HP Notebooks | HP Computers | @HPSupport - YouTube
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