In this I will show you how to make a solar rechargeable automatic led night light. I made mine for outside use but hey you could do whatever with yours! :) 
 How did this idea come about? first I have been meaning to get some sort of light fixture in our back yard, I was going to install an outside light but that fell short once I saw the ratherr poor wiring in the garage. Now the light I wanted shouldnt be so bright but just enough light to see the table and surroundings so I decided to use leds, so I finaly came up with this product. Its a 2l bottle turned into a table light. but its more than that, Its solar rechargeable, and turns on by its own at night. I used a 3.7v lithium ion battery and a charge controller to properly charge the battery, an npn and a LDR circuit. now if you are not familiar with these types of batteries and how dangerous they can be then I recommend using normal batteries such as 4 double As, rechargeable of course. If you charge lithium ions inproperly it could end bad. That being said, do this at your own risk.
before starting give the video a watch :)
it lights at night and charges in the day time

Step 1: things needed.

npn switching transistor (2n3904)
10k resistor
5 white leds
5 volt power supply (needs to be rechargeable ((4xAA batteries should work just fine)) )
blocking diode 
2l bottle

If you change the value of the resistor you can alter the sensitivity of the on/off action. dont change the value by alot because you could fry the npn.
<p>Thanks for sharing... Anyway, Can you share the solar panel details ?</p>
<p>You don't need the LDR, the solar panel can charge the battery and turn the circuit on. Use a PNP transistor so that when the solar panel voltage goes low, the transistor turns on. You'll also need to put a Shottkey diode to the battery so that it's voltage does not keep the PNP base high and keep the solar cell from draining any power.</p>

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Bio: My name is Taylor, Im currently going to school for electrical technology, going to school for what I love. I have been in love with ... More »
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