First steps, Charge the battery, Plug the charger in – Nikon D300 User Manual
Page 56: Remove the terminal cover
Charge the Battery
The D300 is powered by an EN-EL3e rechargeable Li-ion battery
The EN-EL3e is not fully charged at shipment. To maximize
shooting time, charge the battery in the supplied MH-18a quick
charger before use. About two and a quarter hours are required to
fully recharge the battery when no charge remains.
Plug the charger in.
Insert the AC adapter plug into the
battery charger and plug the power
cable into an electrical outlet.
Remove the terminal cover.
Remove the terminal cover from the