The old Flip phone AA pack used six AA cells, enormous by today's standards. But a normal sized modern cell phone could easily be made to run on two AA's. That should run the phone for a lot longer than the typical 900 mah 3.6v lithium ion pack. I just completely despise lithium ion and having to buy more special purpose batteries and chargers for every device that uses them. The very existence of these AA powered chargers for them shows how dysfunctional lithium ion systems are. I'm doing everything I can to select portable electronic products that run on AA's or AAA's exclusively (digicam, mp3 player, flashlights, etc). Cell phone is the one item where it seems near-impossible these days.