Looking to add a rechargeable rc battery and am looking to level out the current along with the voltage. Wondering what i can do to level the over powering battery to suit the board. I am comparing what power the board needs by using the power capabilities of a 9v which can be added on as a backup option. Was looking for a dc power transformer but am having no luck.
Okay... Not quite sure what you are asking there...
Whatever battery you use you will have to give the Arduino 5VDC. If your battery voltage is higher (needs to be 7V or higher) then feed it into the external power connector and the 5V regulator will supply the 5V the Arduino needs. A bigger capacity battery will not "Overpower" your Arduino any more that the power company can "overpower" your appliances at home. More capacity in your batteries will not "overpower" your Arduino, it will just let the Arduino run longer before the batteries need charging or changing.