My ASUS laptop shut down unexpectedly when unplugged. Even with battery charge over 50%.
The OS installed is Linux, and it is set to shut-down at a critical percentage of 5%.
It doesn't look like an OS behavior, which takes some seconds to close all processes
What's happening is a snap shut down in a fraction of second.
How can I find out whats causing it?
This may or may not be relevant, but a similar problem plagues Acer laptops. There is a safety feature which kills power when the hardware detects the case is open (and power is on). By tightening some screws on the reverse of the laptop, the problem magically goes away. The screws are self-loosing so this may need to be repeated every few years.
The problem (with resolution) is described in great detail here.
