Ok folks, I'm countin' on ya here... I'm tired of replacing batteries in electronics. And I know you can get batteries and chargers about everywhere. My problem is that I need to know what sizes to get. For instance, if I remember correctly, 2 of the CR123A batteries are the equivalent of an 18650 rechargeable pack in size, shape and voltage. I dont know if the type of battery changes the part, i.e. nicad, LiOn, etc. So my question is this: Is there a chart or table somewhere that has this information? 'Cause I can't find nuthin! Even if a complete reference can't be found, please post what you do know... 3 AA's = ?????? School me on batteries...I appreciate the help! Edited for clarity and other random thoughts.