Mysterious icon in Notification Area It is on a Sony Xperia T. The first icon from the left that looks like a battery in hands. I checked the manual and asked around. No one knows... There is no information when I drag down the Notification Area.
According to the Xperia Z manual, that icon indicates that "Stamina Mode" is active.

I don't see it in the Xperia T manual, so I'm guessing that there was a recent update to your device that added that feature.