Design, Build, and Test a Solar Powered Phone Charger

In this paper, a solar powered phone charger was designed, built, and tested. Initially, a hydrogen fuel cell was constructed using a series of razor blades, wires, and an aqueous solution of potassium hydroxide. Since the fuel cell failed in delivering power to electronic devices, a four parallel stacks of six NiMH AA rechargeable batteries in series were substituted to deliver roughly 8 V to an Arduino Uno, which powered a DROK integrated circuit in order to provide charge to small electronics, such as cell phones. A 50 W solar panel was used to charge these batteries. To maximize the efficiency of this solar panel, a mount was designed and built using a servo motor and CdS photo resistors that was capable of orienting the photovoltaic cell to the strongest source of light. A program for the Arduino Uno was composed to control this mount to provide power to the DROK integrated circuit, and read the battery stack's relative state of charge and illuminate LEDs accordingly. A switch was incorporated into the design that would cut power to the microcontroller when the prototype was not being used. After constructing the prototype, multiple tests were run both on subassemblies and on the overall device to verify its electrical capabilities, mechanical stability, and aesthetic appeal to a broader audience. Appropriate design changes were made as a direct result of these tests, consequently strengthening the legitimacy of the overall design. Possible improvements include a manufactured hydrogen fuel cell, increased electronic charging capabilities using a simple transformer, and linear actuators to improve the solar-tracking capabilities of the photovoltaic cell mount.