Instructables

Some times one's car breaks down at night in the middle of no where and there may be no light to fix it! For that I have made an easy solution to fix that problem!

An easy USB rechargeable magnetic led assistant!

Step 1: What you need:

Picture of What you need:

You will need:

  • Some skills!
  • 1w/2w/3w leds (one or more. Actually one 2/3w led will do. if using 1w use two of them)
  • A small 3.6v ni-dc 100mah and higher button cell battery (use more mah count battery if using more leds/more watt led)
  • Male USB port
  • small Perf board
  • Magnet
  • Soldering Iron and soldering wire

Step 2: Prepare your board

Use the schismatics above, it will help you...

Remember: Connect the USB +5v to the positive side of the battery and GND(ground or negative) to the negative side of the battery. NOT vice-versa or you will screw up the battery or the usb port!

efahrenholz6 months ago
This is a fine idea, but you really need a few more components to limit charging current to the battery. Try adding a series resistor to the 5v vcc. Nicads will charge over 1c, so the only safe way to charge that little battery without it catching fire is a usb on a regulated system. I wouldn't recommend trying this on a wall wart based usb charger.
pawanvs99 (author)  efahrenholz6 months ago
Thank you! Yes I know we need a limiting circuit for the battery... but charging it for less than 30 mins will do good. One can also turn on the light when its charging to see how bright it is when it is being charged and then turn off the charger to see the level of brightness. That way one can see the level of charge! I totally agree with what you said!
I shall include that in my ible!