03-16-2017 08:31 PM
Can I use the Laptop without battery, only power adapter...
Yes, you can. I am not sure why you would want to but it's possible. Here is the OMEN by HP Laptop PC Maintenance and Service Guide which will show you how to remove/replace the battery and etc.
Personally, I recommend leaving the battery in at all times because a power failure (accidental disconnect of AC adapter, brownout, outage) might cause data loss/system corruption on your system.