In 2014, we were assigned a group science project that involved making a device that can make everyday life easier. The device also had to involve some type of energy transfer. I chose to work with my two friends: Jason Fan and Eliot Min. As we began brainstorming, we were drawn towards the idea of charging an iPhone. The iPhone is a huge part of life in the working class, so it made sense to transfer some type of energy to power an iPhone. We browsed the internet, and found something called a Solar Powered Backpack Charger. The idea was a backpack with solar panels built on its surface could power several devices.
Step 1: Planning
We checked several versions of the appliance, and decided to come up with our own unique idea. We began simplifying the design. Most versions had several large solar panels on its surface. We decided to cut it down to one solar panel, due to a limited budget. By doing so however, we had to change the schematics. We decided to have a usb female along with a circuit board to adapt the wiring between the solar panel and the iPhone 4 charging cable.
Step 2: Experiments
We needed to find a USB female. A USB female is the socket where a regular USB (male) is inserted. We broke down a USB hard drive only to realize that the USB female was not compatable for our device. Later, we broke apart a USB car charger. We were able to test the circuit by substituting the solar panel with a set of batteries (left image). This time it worked perfectly. It even had a nifty blue LED that lit up indicating an electricity flow.
Step 3: Trial
The next step was to attach the solar panel, which required using a soldering iron. We soldered the wires onto the solar panel. From the previous trial, we found that it was necessary to add a diode. The diode regulates electricity passing through so that the circuit board would not overheat. Unfortunately, electricity was not passing through for some reason, so we decided not to add the diode. We later found that the diode was not necessary, because the solar panel always kept below 6 watts, which the circuit board could easily handle.
Step 4: Finishing touches
The last step was to embed the circuit into the briefcase. Using super-glue and electrical tape, we got the contraption to fit in the briefcase snuggly. The apparatus worked perfectly when we demonstrated it to our class.
This project was such a success, some of our classmates asked if they could purchase one. However, his device still has a lot of room for improvement. Like I told my class, the ideal owner of this device would likely be a businessman who regularly goes to the beach.
SOLAR BRIEFCASE IPHONE CHARGER
