Tuesday, November 21, 2017

windows 7 - Battery stops charging at 84% and gets very hot


My laptop battery always charges to about 84% to 87%. Once it reaches a charge level in that range, it stops charging, but Windows says it is "plugged in and charging". Because it has not reached 100%, it keeps trying to charge the battery, but instead of charging it gets very hot. It causes CPU temperatures of about 51°C (normal temperatures range from 35°C when idle, to 43°C when running an IDE and a compiler).


The machine is an HP Pavilion dv7-6157cl running Windows 7. I have set the fan in the BIOS to run continuously, and it is always on a table or some surface which allows plenty of airflow to the vents on the bottom.


I have reinstalled the battery drivers and updated all of the other drivers. Nothing seems to help. I have also tried calibrating the battery. I also tried changing several power settings. The problem persists.


However, it works correctly as long as the charge does not exceed 84%.


What might be causing the problem? Is there a way I can get Windows to stop charging the battery at about 80%? Should I get a new battery?


Answer



Battery heating can be a sign that there's a bad cell in the stack.


The other cells charge up to full capacity and the bad cell then just turns into a resistor, creating a lot of heat as it dissipates the wasted current, and in the case of Li-Poly, eventually smoke.


No comments:

Post a Comment

hard drive - Leaving bad sectors in unformatted partition?

Laptop was acting really weird, and copy and seek times were really slow, so I decided to scan the hard drive surface. I have a couple hundr...