The link below which describes the external and internal battery and why the Emergency reset is used.
Procedures or Details
***Remember this option should be used for EMERGENCY as a last resort only, as this could damage hardware as well as OS if used often.
NOTE: Before trying the below, try a couple of options, like pressing CTRL + Alt + Delete button and see if you can restart or end the service that may be the cause of the computer freezing.
Check the power adapter as this might be bad or the connector might be lose.
IF NONE of the above work, then:
- Unplugged the power cord
- Use a paper clip and push into the Emergency reset hole and release it.