Have you checked that the fan vents on the bottom of the laptop are clean and clear of dust etc you didn’t say?
Can you hear if the laptop fan is operating or feel the air coming out of the vent indicating that the fan in the laptop is operating, you didn’t say?
If you can’t hear the fan or feel the air coming out of the vent then there may be a problem with the fan.
As the laptop is only 2 years old there shouldn’t be a problem with the thermal paste on the CPU drying out yet which can also cause overheating. usually it takes about 4 years for this to occur but it may depend on the environmental conditions where the laptop is located I suppose
These are the two major factors that cause overheating in a computer i.e. faulty fan (or blocked vent) and dried out CPU thermal paste.
Here’s the service manual for the laptop, taken from this webpage.
Go to p.43 to view the necessary pre-requisite steps and then the procedure to remove the fan. This will allow you to check that it is still connected properly and also to see if it is working OK or not.
I don’t know what you used to ascertain the state of the battery but get a second opinion as to its condition by creating a Win 10 battery report. In the results check the Design Capacity value in comparison to the Full Charge capacity value to see if it is also at ~54%, (you have to do the maths ;-) Batteries are meant to be used and if not regularly used and charged can deteriorate and eventually fail.
Hopefully this is of some help.