How to Construct a Charger for Li-Ion Phone Batteries
- 1). Strip an inch of the wire covering off of the USB adapter to expose the red and black wires.
- 2). Solder the red and black wires to the first and second pins on the 5-volt integrated regulator.
- 3). Take your alligator clips and strip the end off of the cable, leaving the clip end intact.
- 4). Solder the clip wires to the last pin on the regulator.
- 5). Connect the red alligator clip to the positive terminal on your battery and the black clip to the negative terminal on the battery. Any standard battery, such as a AA or 9- volt battery will charge the phone.
- 6). Connect one end of the USB cable to the USB adapter and the other end to the port on your phone. Make sure the USB cable you purchase from your retailer is compatible with your phone.
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