Hi, my name is Bennett Liu, and I am a rising sophomore at Colorado Academy. When I was young, I was always fascinated by engineers’ ability to build anything, almost as if they possessed a superpower. My interest for engineering has only grown from there on. I especially have an interest in bringing renewable energy to third world countries. My starter project is the minty boost, and my intensive project is the solar powered battery (inspired by hackaday.io). I am excited to build a solar powered battery and will hopefully be able to turn it into a final project in which I can bring it to a third world country where electricity is not as accessible.
Even though I only had two weeks at BlueStamp Engineering, I learned a lot about circuitry and electrical engineering.This was my first experience in engineering, and even though I did not know what I was doing for most of the time, I feel inspired to learn more and dig deeper. The freedom of this program, unlike the rigid structure of the school system, taught me that sometimes the best path to learning is failure. I thought that my project would be predominantly mechanical energy, but it was all electrical. Electrical systems are complex and fickle, but when it works in the end, it is rewarding. In the future, I will definitely consider a career in renewable energy.
For my final milestone, I hooked up my solar panel system so that it could read me data for the battery percentage, voltage, amps, watts, and battery health. In order for this to happen, I had to implement the battery babysitter, and arduino uno into the system. To do this, I connected the solar panel to the lipo usb charger. The lipo usb charger’s job is to take the power of the solar panel and convert it into the appropriate voltage and amps to travel through the battery babysitter. Then, I connected the battery babysitter to the lipo usb charger. I did this by grounding the negative wire into the voltage in port, and soldering the positive wire into a lead that reads the voltage coming through. From the battery babysitter, I connected the battery into battery socket, and I connected my mintyboost into the voltage out leads. Finally, to get the readings I connected wires from the battery babysitter to the arduino into the VPU, SDA, SCL, GPOUT, ports and grounded the system. Once I had the electrical side of the project set up, I had to work with the software and programming to get my readings. There was a library for my code on the internet, so I downloaded and used it; however, the program did not work at first. I had to fiddle around with it a little, but finally I got it to work. The second problem I ran into was that how the system was hooked up, it disabled me from being able charge my phone and the lithium ion battery at the same time. The battery had to be charged in a port, then removed and put into another port to charge the phone. This gave me strange data from my arduino. So, I looked at the schematic of of the battery babysitter and soldered the positive wire from the lipo usb charger to a lead that reads voltage directly from the BQ27441 chip. This solved my issue and now the circuit runs through from the solar panel to the phone.
My first milestone was connecting the basic solar panel system and testing the efficiency of the power going from the solar panel to the battery and the power going from the battery to the phone. In order to find the efficiency, I had to test for three readings: the current, voltage, and power. To find the current, I made a break in the positive wire and tested the current with the meter. To find the voltage, I used the charge from the positive and negative wire. To find the power, I simply multiplied the voltage by the current. Once I had the power, I found the efficiency by dividing the power going in by the power going out. The first test I did to find the efficiency of the solar panel to battery gave me a 51% efficiency, which seemed low. As a result, I did a re-test, but this time, I drained the lithium battery first to make sure that the fullness of battery did not play a role in determining the efficiency. On the second test, the efficiency was 81%, much more of a reasonable efficiency. Then, for my second test, testing the efficiency from the battery to the battery to my phone. The efficiency was 71%.
I chose the Minty Boost for my starter project because it has helped me learn about the electrical side of engineering which will help me with my intensive project, a solar powered battery. Also, because battery power is unfriendly to mother nature, I am going to try to connect the minty boost to the solar powered battery so that the power is renewable rather than wasteful. The minty boost works by converting the high voltage of the battery to the low voltage required to power the phone through resistors. Here is a video of the minty boost working and a description of all the elements that goes into the making of the minty boost.