Nikon D7000 User Manual page 84

Choose whether the battery in the camera or the batteries in the
battery pack are used first when an optional MB-D11 battery
pack is attached. Note that if the MB-D11 is powered by an
optional EH-Sa AC adapter and EP-SB power connector, the AC
adapter will be used regardless of the option selected.
A _ icon is displayed in the camera control panel when the
batteries in the MB-D11 are in use. The information display
shows the type of battery inserted in the MB-D11 as follows:
i--_!°on_!!i:°'° I Battery type
EN-EL15rechargeable Li-ion battery
_] AA batteries
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