By Evan Ackerman
Yes, I know that this thing is most likely not real, especially since it’s from a company called “Naivetek.” The idea is you stick D batteries in one side, and it charges up AA or AAAs on the other. It sounds silly, kind of like the solar powered flashlight, but it actually could end up being something useful.
Disposable D batteries have a typical capacity of 12,000 mAh, whereas rechargeable AA batteries normally have capacities of 2,500 mAh or less. It looks like this thing can hold maybe 4 D batteries on one side, and 2 AAs on the other. So hypothetically, that gives you 48,000 mAh capacity with which you could recharge your AA batteries 9 or 10 times. Say you’re off camping for a week and need to keep your camera running… Would you rather carry 10 sets of AAs, or 1 set of AAs, 4 Ds, and this charger?
Guess what? You can actually do this by taping D batteries together with any lower size.
um… 10 sets of AA's actually – it would take up less space and would weigh less. That said, I agree Naivetek is probably a big hint.
You would never actually get all of the MAh out of the Ds and into the AAs. Large amounts would be dissipated by heat. Also, rechargable batteries need more wattage than that to charge efficiently. Ultimately, I suspect 4 D cells would be able to charge 2 AA cells about 1/2 times, but it could be used as a pocket warmer in the mean time.
You would never actually get all of the MAh out of the Ds and into the AAs. Large amounts would be dissipated by heat. Also, rechargable batteries need more wattage than that to charge efficiently. Ultimately, I suspect 4 D cells would be able to charge 2 AA cells about 1/2 times, but it could be used as a pocket warmer in the mean time.