Why is choosing a simple AA battery such a daunting selection process?  Manufacturers are keen on giving their products different names and brag about the chemical technology that makes them up.  However, it is nearly impossible to make package-to-package comparisons of the battery’s capacitor.

Denis Hennessay has a GREAT write up on Measuring Battery Capacity with an Arduino.  In addition to full details on how his project works, Denis even shares the results of several AA batteries.  Nice!