The inherent technology in rechargeable batteries has been advancing, with interesting options for users. Duracell offers a Ni-MH charger with AA and AAA (the most usual ones) capability and a surprising recharging time of 15 minutes. Although that time is not for a 100% charge nor to those batteries that have more capacity than alkaline ones (up to 2500mAh), with a little quantity of time the user could get a 50% or 75% charge, enough for quick applications, especially for those who constantly employ portable devices.
The model Duracell Ion Speed 8000 is capable of charging four batteries at the same time. It has another option not usually seen: “Bad battery indicator”, and auto shutoff when batteries are fully charged.
The quick charger comes with two rechargeable batteries with warranty for five years. Not bad, and Duracell says that these batteries “[...] are 50% longer-lasting per charge” in this condition: “Duracell NiMH 2400mAh AA vs. 1350 mAh within the first 200 cycles”. They could last 100% more comparing them with 500 mAh ones […], this marketing sentence seems pretty logical!
Technically the quick charger provides 8000mW, being equal to 8W. With four 1.2V AA batteries you add approximately 4.2V and then applying the equation for power (I = P / V) the result is 1.9A each battery and 3.3A per battery charging two (8000 / 2.4).
Usual quick chargers provide 1A per battery and charging a maximum of two batteries. This charger is very audacious, and it must have a good construction for handling high temperatures (did you read somewhere “Active cell cooling”?) during charging and security measures.