Hey everyone!
years ago I developed a ESP8266 based door/window sensor that runs on battery. The whole system is set up to last up to 2 years on one CR123A battery (yes unusual, but fitted perfectly for my needs).
I designed my own circuit and wrote the necessary SW. The Box is meant to be 3D printed. I made multiple versions depending on the place it is supposed to go (more or less space)
I promised to share the project here back then, but never got around to it.
If anyone is interested, you can find everything across 3 repos on github:
https://github.com/BigFood2307/ESP_WindowContact_Box
Here a couple pics to give you an impression:
Feel free to ask me any questions regarding this project!