Heat Flashlight
This project represents my abilities in 2019
The Heat Flashlight is a project that I've always wanted to do, but didn't have the tools to do so until this summer. This was the first project that utilized the 3D printer that I built, and is comprised of a plastic housing as well as some electronics, all of which is detailed in the following sections.
CAD Exploded View
I designed the housing of the flashlight in SolidWorks. There were several design constraints that I had to work around, including the size of the peltier tiles and ice capsule that I had selected. The design consists of three printed parts: the body, LED cap, and the cap that secures the ice capsule to prevent its movement within the body.
Ice Capsule between the Peltier Tiles
The thermoelectric capability of the flashlight is enabled through the use of Peltier tiles. Peltier tiles are made of silicon material sandwiched between two layers of ceramic, and they heat one side and cool the other when power is applied to them. I'm using this same property, but in reverse, to create power by heating one side and cooling the other. The users hand heats the outer wall of the tile, while the ice capsule cools the interior wall.
In my testing, the peltier tiles were only able to create 0.1V, which I needed to increase to 1.8V for the LED. I achieved this through a circuit containing the tiles in series and a component known as a boost converter, which can increase DC voltage.
After soldering together all the components, the flashlight worked perfectly. After the user places the ice capsule in the base of the flashlight and grips the exterior, the light turns on almost instantly.
Final Flashlight Brightness