AA vs AAA Batteries:

This battery holder is designed for two AA batteries, while the battery holder that comes with

micro:bit Go Bundle is suitable for two AAA batteries. So what's the difference? The capacity!

AA battery is bigger in size than AAA battery. Since energy storing capacity is proportional to

the size of the battery (within the same chemistry type), AA battery can supply power to your

application for a longer time. Generally AA batteries have about three times the capacity of

AAA batteries.