The Peltier element is a thermoelectric converter. It works as follows. When current flows through its elements, one side of the Peltier element is heated and the other is cooled. If you change the direction of the current, then the sides of the cooling-heating will also change. Also, the operation of the Peltier element has the opposite effect, when heating one of the sides (or cooling) at the output, we get a current. The author decided to take advantage of these amazing physical features of the Peltier element. The author decided to make a lunch box in which, regardless of the time of year, you can heat or cool the food.
Tools and materials:
-Lunch box;
-The Peltier element;
-Solar panel with battery;
-3-position polarity switch;
-Two metal plates;
-Two sheets of polystyrene;
-Soldering iron;
-Glue;
-Knife;
Step One: Panel Installation
On the lid of the box marks the place under the solar panel. Cuts out part of the cover. Sets the panel into the cutout, fixes it with glue.
Step Two: Switch
Cut out a place for a switch in the lid. Installs it.
Step Three: Install the Peltier Element
At the bottom of the box draws the outline of the element. Cuts the marked out part. On the outside, the bottom of the box, glues a metal plate. Glues the Peltier element on a metal plate. Lays on the bottom a thermally insulating material, having previously cut out a place under the Peltier element. Glue a second metal plate on top. Connects the wires of the Peltier element to the solar panel through a switch.
Step Four: Polystyrene
Cuts polystyrene according to the size of the lower and upper inner part of the box. Sticks it.
Lunch box with the possibility of cooling or heating is ready.
A little on my own, for those who decide to do something like that.
1. The Peltier element must not be glued, but installed on thermal grease.
2. The author did not indicate those. characteristics of the element and the solar panel. But if necessary, all the information is online.
3.According to my information, the wiring of the three-position polarity switch is as follows: middle legs (2 and 5) + -, and crosswise 1-6.4-2.