I am developing a remote module (not wired to a computer) that has an Arduino Uno board, 5 volt hall effect sensor, xbee radio and data logger connected together. On this remote module,the data from the sensor will be recorded to my data logger every 15 or 30 minutes. The xbee radio though would need to be available the vast majority of the times.
For the xbee, I will configure the sleep mode the best I can to preserve battery. Ideally, I would like this to last a couple of years (as long as possible ) without changing/charging the battery. For now, I am purchasing the hardware.
I wanted to ask what is the best battery I can purchase for this (i.e lithium, how many volts etc)? For this much time, I am thinking that I should use a few batteries and have something autotmatically switch or share power among batteries. Which switching regulator and battery would be good for this project? If need be, I can purchase a voltage regulator if it's needed.