I've been working on a AA-battery module for my old Motorola for months! The batteries fit in the space under the extended-battery caseback, but their 2.4v output doesn't meet with the phone's 3.6v expectation, so I'm trying to build a small boost converter. Except I'm not very good at it, nor am I very diligent.

Ham radios have come with AA-battery auxiliary cases for years, because we all know you don't always have a charger handy. It's almost criminally stupid that cellphones, which the majority of the population now rely on for emergency calls while traveling, don't offer a similar option. Well, I guess they do now!

Once upon a time ago I accidentally realized cellphones have removable battery packs. Ok, it was a long time ago but anyway, why not just take a spare battery pack with you instead of AAA cells?

I realize it means on the road you can't buy the spare pack so easily but then it makes more sense to adopt a universal battery pack standard for cellphones instead of sticking with proprietary and then adding bulk to house a AAA cell too.

Taking a spare battery pack involves buying a spare battery pack - often quite expensive - that you may never need. You'll have to carry it everywhere, and make sure you keep swapping it over and charging it, because they can self-discharge in a matter of weeks.

An AAA holder will always be handy, as long as you're somewhere near a shop, or even near something that you can pinch the battery out of (a remote control, for example).