I am just getting started and I want to connect an ultrasonic distance sensor to an Arduino Nano and power it using a rechargeable battery. I've been looking about and there seems to be different options for powering the Nano but I like something like the Adafruit LiIon/LiPoly Backpack. I found this in relation to powering a Pro Trinket here.
The thing I am having trouble understanding is around the supply voltage. The supply from the board to the sensor seems to be 5V and the backpack has 3.3V. I am just making the assumption of using this backpack for illustration at the moment. Do you need a battery that can supply 5V? If so are there any recommendations for one that could fulfill the role?
Thanks very much.