Disk Depot Articles » What Different Types of Batteries are There, and What are the Differences Between Them?
Energizer e2 Lithium AA Battery, 2900 mAh, 1.5 V, Pack of 4 - Walmart.com
Amazon.com: Energizer Rechargeable AA Batteries, 2,000 mAh NiMH, Pre-charged, Chargeable for 1,000 Cycles, 8 Count (Recharge Universal) : Everything Else
If an alkaline AA battery is rated at 2700 mAh when brand new, what is the capacity of the battery when the particular device (i.e. wall clock) drains it fully and stops