Inspired by this https://www.thingiverse.com/thing:3091337 I decided to design my own light, that is easier to print.

I made 2 versions in Fusion360, one to fix with fasteners below at the seat post and the other with an adapter to existing clip-on lights.

For the diffusor plate I used a transparent filament and scaled it a bit up in the slicer, because the first version kept falling out after a few rides.

I used a 5V LED strip and used XT-30 plugs for easy taking of, and then connected it to the existing light cable of my E-Bike.

You can probably also modify it to use some kind of battery for normal bikes.