Sony PCG-R505GCP - Manual (Page 13)

Frequently asked questions
How do I know when the battery is charged?
To determine the remaining battery charge, see Displaying battery information.
When is the computer using AC power?
When the computer is directly connected to the AC adapter, it uses AC power, even if a battery is installed.
When should I recharge the battery?
 When the battery level falls below 10 percent.
 When both the battery and power indicators blink.
 When you have not used the battery for a considerable amount of time.
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