Hi, I'm looking to measure and display the power level of a rechargeable battery through arduino. Is this possible and if so what are your recommendations?
Yes is possible. There are many threads on it. Basically bring voltage in to an analog pin, scaled down with voltage divider (2 resistors) to meet 0-5V range of the input (assuming you are running from +5V one way or another). Battery ground connected to arduino ground. value = analogRead(input_pin); value * (5/1024) = your voltage.
Here is how I did. :)