A very simple method to get double output voltage within the space of a single AA battery. Useful for strengthen your single battery powered device, eg. flash light, nose hair trimer and etc.
Step 1: reason
Sometimes you are not satisfy with the POWER of your single battery powered device, such as your dim tiny flash light, tooth polisher or the MOST common used nose hair trimmer.
For me, I have changed a lot of them but they are all slow even when I use a NEW battery.
Each time I used them I sweared to put TWO batteries inside it someday.