Power suggestions for Arduino sensor shield

Hello Arduino community,
I am working on a project that will use two 9g servos, a led matrix and some sensors. The current required (that I calculated) is around 2A. In my case, I have a pair of batteries that, connected in series, will make up to 7.4v and 3A. The issue I have is that all my parts (the servos, matrix,sensor, etc) use 5v.

Do any of you know anything I can add or do so that I can make the 7.4v -> 5v and still keep the 3A?

In case the battery are useless, please recommend a battery to power it.

Thanks!
If it is of any help, the sensor shield I am using is attached