To continue my DIY Solar Lantern project, I’ll now talk about the charging module. This is composed of the Nicad battery, Solar Cell, and a diode.

Charging Module

A diode is an electronic component that allows current to flow to one side but not the other way. For solar charging, we would be using a diode to allow current to pass from the solar cell to the battery.

However, during night time when there is no sun, a small current goes from the battery to the solar cell. This is what we would like to prevent and the diode blocks that current.

This is a simple charging circuit but it does not protect the battery from over charging. Maybe in the future, I’ll design something that would automatically switch off the charging process once the battery voltage goes to a pre-determined value. But for now, I’ll just make my DIY solar lantern as simple as possible.

Overcharging is the number 1 cause of battery damage. So for now, I’ll just have to estimate the number of hours I’ll leave my solar lantern under the sun.

The Solar Cell

I’ll be using a mini solar module (solar cell) which has an output voltage of 5v and a current of about 70mA at full sunlight. (This makes about 0.35watts of power).

How long does it take to charge the battery?

This depends on the capacity of the battery. In my case, I have a 280mAh Nicad battery. If my battery is fully depleted, it would take around (280mA/70mA= 4 hours) to fully charge.

Putting it all Together

First is to make a hole at the center of the canister cover. This is where the wire from the solar cell would pass through. I outlined the underside of the solar cell with a double adhesive tape so it will stick well on the cover. This also protects the solar lantern from getting rain so that water won’t go into the center hole where the wire goes. (It is not water proof though so I don’t suggest leaving yours outside if it rains). I might put some silicon someday (the one used in making aquariums) to make it waterproof.

On the underside, I also added a double adhesive tape to close the center hole where the wire passed through. I added some more double adhesive tape and then press down my Nicad battery. I then drilled a hole for the switch.

To be continued….

Technorati Tags: diy, diy solar lantern, solar lantern, solar gadget, solar led lights, solar powered light

australia home loans 106cash $5000 loan2007 loan car usedunsecured loan 25000alabama quick loan cashloans 40,000 studentservice loan acsloan ace funding Map

536 credit ratingdirectory program casino affiliatefree affiliate casino programcredit abacus unions australiastep earning credits ad time visitorscasino dice 3bonus deposit 20 casinocredits 14 three 411vm volume issue Map