I get the idea from this forum thread:
https://www.hovatek.com/forum/thread-38775.html
I used 2x 1000uF/10v electrolitic capacitors in paralel, 10k resistor, 10ohm resistor and piece of copper wire. After soldering everything I covered connections with hot glue.
Battery contact points are made by wraping piece of copper wire around groves in printed frame.
Initial test shows that it works.
Printed with 0 bottom and top layers, 3 perimeters, 20% hexagonal infill. I did it that way for better ventilation.
The author marked this model as their own original creation.