And am planning to run the arduino using 6V battery source.
That part might be a problem. Anything over 5V implies you're powering the Arduno via its internal voltage regulator, but that needs 7V or more to produce 5V. If you supply the voltage regulator with 6V (or perhaps less, when there are other loads on the battery) the actual voltage on the 5V line will be less than 5V. That might cause stability problems, so if you take this route test it carefully and be prepared to look for other options.