Sony vaio vgn-p Benutzerhandbuch

Can my computer enter Hibernate mode while running on battery power? 

Your computer can enter Hibernate mode while running on battery power, but some software programs and peripheral 
devices prevent the system from entering Hibernate mode. If you are using a program that prevents the system from entering 
Hibernate mode, save your data frequently to avoid losing data. See Using Hibernate Mode 

 for information on 

how you can manually activate Hibernate mode.

 

Why doesn't the charge indicator light go out when it seems the computer and the AC 
adapter have been connected for long enough?

When the temperature is below approximately 59°F (15°C), the battery pack (VGP-BPS15 or VGP-BPL15) is designed to 
charge to approximately 80% capacity. In such a case, the charge indicator light remains on while the computer is connected 
to the AC adapter. However, this is normal and does not indicate a malfunction.