Solar Cell(phone)

Inspiration

The EE 185 class was going to throw away a box full of perfectly working solar cells. Individually they could barely charge a AAA battery, but together they can charge a phone. I decided to take them along with some other used parts from the Industrial Engineering building and make something useful out of the otherwise considered junk.

What it does

You can either plug your phone directly into the USB port and charge it using the sun or charge a battery bank and use the battery to charge your phone later when it's dark/cloudy.

How I built it

With 6 cells in series and five of those rows in parallel, enough current and voltage can be generated to charge a phone. Pass that power through a voltage regulator circuit to make sure that the voltage stays constant and you have a cellphone charger.

Challenges I ran into

Design issues were a huge problem. Making something functional and making something presentable are two very different things

Accomplishments that I'm proud of

I am proud that I have a finished product that, in my opinion, looks rather nice. I'm also proud that I didn't stop when I was done with that project and that I started another project. Even though I did not finish the LED clock that I started, I am proud of the progress that I have made.

What I learned

I've learned that when connecting the cells together, the best way to do that is by measuring the current and putting like-current cells in series, as the current is the limiting factor. Also, never be afraid to ask for help from someone with more skills or equipment than you.

What's next for Solar Cell(phone)

I would like to make a PCB for the voltage regulator and maybe re-re-design the whole thing with an Industrial Design major to make it look even better. I finished the solar panels rather quickly so I started working on an LED analog clock. I was 4 LED's short out of 181 LED's used total, so I will buy more LED's, wire everything up and write the Arduino code for the LED clock.

Built With

• battery
• solar-cells
• voltage-divider-circuit