Mercury 9.9hp 4 stroke outboard 2011 rectifier

[boatfishermalta]

i have just purchased a mercury 9.9hp 4 stroke outboard,
what do i require to charge a battery? the dealer i purchased the motor from told me that i only need a rectifier, would you be able to help me with this problem?
thanks
paul

[boats.net]

What is the serial number from your motor?