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can i use 4 AAA rechargeable batterys for my usb altoids charger without capacitors or anything?

i want to build altoids usb phone charger. i have 2 options using 9v battery and 5v voltage regulator, or using 4 AAA rechargeable batterys without anything expect female USB . So can i build 4 x AAA usb charger and what else i need ( diode, capacitor,....)?

tealk (author) 1 year ago
Then, can i use 6 aaa rechargeable batterys with voltage regulator? That is 7.4 volts or more because rech. Bart. when they are recgarged they have 1.3-1.4 volts
quatch1 year ago
neither of those have the capacity to charge a phone.

Have a look at: http://www.ladyada.net/make/mintyboost/
Setting aside the fact that the 9V won't last very long and the 4x AAAs will output more than the 5V your phone needs... they both have the capacity to add a bit of charge to a phone. Much more so than the Minty Boost can with a single AA. A single 9V battery and 4x AAAs have more overall power to give then a single AA in the minty boost. The Minty boost takes the 1.5V of the AA and boosts it to 5V while sacrificing amperage. You don't get any more power out of the battery then you would if it was on it's own. In the end your still only getting a single AA's worth of power into your device minus the bit of energy lost in the minty boost doing the DC to DC conversion. But that loss is much less than you loss putting the 9V through a 7805.
rechargables are 1.2v each nominal; they'll total 4.8 which might work for some usb devices but many might be angry about it.
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