Summary

I looked for a long time for effective way to mount power bank on my helmet so the action camera will last for many days of use, And haven't found something simple that fits few power banks models.
This is my best solution up to now and it allows me to mount 2 different types of power banks (not at the same time of course).
The power bank can be attached to the surface with : Rubbers/Velcro/Double sided nano glue.
You can basically attach ANYTHING with this adapter.
It has to notches underneath so you can use it with thick rubber in order to attach stuff.
I also bought the red aluminum adapter part via aliexpress :
https://www.aliexpress.com/item/32906586967.html
(You can print/buy plastic base for the mount, But from my experience with them - They break after few months at most, And this part I'm using for more than a year now).
I've connected it to the helmet with 2 short screws (I've put a piece of nano tape between the base mount and the helmet before screwing it to the helmet).

Update : I've also uploaded another flat mount for bigger battery that connect from it's edge and have more support slots at the buttom