Originally posted by stevebrot One word in caution: HEAT
Probably yes, although the charging current via USB can be reduced, along with increased charge time, that's not great.
I bought a usb charger so that I'd be able to recharge my D-LI90 on the go, and for me that was an eye opener, as I now think I'd not have much use of usb charging on a camera, I'd still use an external charger anyway. Let me explain...: the charging time of a D-LI90 is about 6 hours, so I need to have two battery anyway, one in the camera and one spare. If the camera in body is discharged I don't have time to wait for a usb recharge in camera, because it is much faster to remove the empty battery from the camera and insert a fully charged one. I have some use of the external usb charger for charging a spare battery in the car while driving, otherwise recharging batteries over night in the hotel room with the normal BC90 charger is just fine and it costs nothing. IMO, USB charging in camera is more for adding some extra charge when not using the camera but not a substitute for charging batteries externally.