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USB battery Answered


Last summer I made a solar charger(maybe I'll post some pictures), I used a 5v 320mA solar panel, 5V regulator and a USB port.
So now I can charge my cellphone and mp3-player through USB.
This works fine, but I would like to make an USB battery that I can charge and take with me..

Something like this http://www.dealextreme.com/p/rechargeable-usb-emergency-power-backup-pack-2400mah-3060

I have no clue on how to make this.
Can anyone help me with this ?

I have some li-poly batteries so I would only have to know wich electronics to use and how to solder them :)

The battery pack should be charged through USB and have and USB output :)

Thanks in advance,



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9 years ago


A unit with two USB leads - a male jack to charge from the PC, a female to plug in the device you want to power.

Attach suitable diodes to ensure that current flows from PC to battery, and battery to device, rather than the opposite direction.

Should be a fairly simple job, just remember not to plug a device into the battery while the battery is plugged into the PC, or you'll risk over-loading the device.

(Having never done this, please remember to insert as many caveats as you can, and that free advice on the internet is often worth less than you paid for it.)