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Is it possible to use a usb recharger to charge a 12v power source? Answered

   I'm new to electronics and was wondering if it was possible to use a usb charger to recharge a 12v power source.  I'm pretty sure it's not possible but i dont know where to look to find a definite answer.  Any help would be appreciated.
   Some extra info: the usb would only need power to go through it, no data.  I'm still deciding on a 12v power source to use.  Sorry if this is a stupid question but I'm still learning.


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Best Answer 9 years ago

USB is a 5 Volt bus which cannot charge a 12 V battery
with the necessary 13½ VDC.

But you said possible and the answer is a definite YES

You have to build an UpVerter to raise the voltage at the
expense of current but it is possible to charge a 12 volt
battery with about 100ma.....



9 years ago

In order to charge a battery you have to put in more voltage then what the battery puts out. You have to push electrons into the battery. If the flow of electrons is weaker then what the battery is trying to output then nothing gets in.

If you want to use a 12V power source to run USB devices you'll need to use a voltage regulator to bring the voltage down to 5V.