USB Powered Laptop Charger





Introduction: USB Powered Laptop Charger

About: Youtube:

Hello everyone,

In this instructable, we will be reusing a defective wall adaptor as a USB powered laptop charger.

This example is intended for macbook air users but this charger can be altered to be compatible with other laptops.

This is a slightly modified version of this instructable by blorgggg

Youtube Version of this project is available here:

Step 1: Parts

Components used in this project:

Enclosure: Magsafe 2 Charger or Junction box

Magsafe wire

Step up Voltage regulator

Small voltmeter with display

USB cable

Step 2: Disassemble

Using this video as a guide, disassemble the macbook charger using pliers.

Since this is a defective wall adaptor, only the outer shell and the charging cable was utilized for this project.

Additionally, the silver ground pin should also be removed for USB cable access.

In order to monitor the voltage display, the power pins have to be removed using pliers.

Step 3: Connect

Output: Connect the ground wire from the magsafe cable to the - Out connector.

Output: Connect the positive wire from the magsafe cable to the + Out connector.

Output: Connect the ground wire from the voltmeter to the - Out connector.

Output: Combine the white and red wires of the voltmeter together and connect it to the + Out connector.

Remove the micro usb from the usb power cable and thread it through the ground pin hole.

Input: Connect the ground wire from the usb cable to the - Vin connector.

Input: Connect the positive wire from the usb cable to the + Vin connector.

Solder everything together and make sure that all the wires are secured.

Step 4: Assemble

Use double sided tape to secure the voltage regulator inside the enclosure.

The input side of the voltage regulator should face the top of the charger where the usb cable is connected.

The output side of the voltage regulator should face the bottom of the charger where the magsafe cable is connected.

The voltmeter should be mounted at the corner of the charger so it can be monitored visually.

Once all the pieces are in place, use hot glue gun to glue all the components to the enclosure.

Before closing the enclosure, drill a hole next to the potentiometer so that the voltage can be changed.

Step 5: Done

After sealing the charger shut, adjust the potentiometer to match your laptop's charging requirements. (macbook air charges at 15v)



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    11 Discussions

    Awesome! yours looks prettier than mine!!

    Apart from the design, always beautiful with Apple, I don't see the utility of this device. Well, it's a voltage converter from 5v to 15v, but it is far too big for its power. It can only deliver 10w which, to my opinion, is not enough to feed a MacBook. (Converter accepts 2A max, in or out, so 2Ax5v=10w)

    Never connect its input to a standard USB port, it will burn.

    2 replies

    Sorry, I didn't see that's a charger, not a supply. Of course, it works even limited to 10w.

    Sorry, I didn't see your answer until today. A USB port is able to deliver 0.5A max, this is the standard, not my wish. If you ask it to furnish 10W it must deliver 2A which it isn't able to do and it will burn, try it if you've got an USB port to loose, or more !

    Last time I took apart a Mac charger it took a sledgehammer... Nice work for getting it apart so cleanly!


    2 years ago

    This device can damage your laptop battery ?

    1 reply

    no, but it will only charge it effectively when the laptop powered off, and it'll still be on the slow side.

    Cool USB Powered Laptop Charger! I could've used this many times when I didn't have access to 120V power!

    Why should I charge my battery with another battery? I would probably need another battery to charge that one. And another to charge that one. And ...

    Is it very slow? Why such a big case?