Here is my project for a portable power supply.
I'm using parkside batteries (20v)
buck boost converter from aliexpress :
https://fr.aliexpress.com/item/1005004271286303.html
Jack plugs : https://fr.aliexpress.com/item/1005004654096753.html
XT60 Plug : https://fr.aliexpress.com/item/1005004731161841.html
male connectors : https://fr.aliexpress.com/item/1005002765359666.html
hot glue for connectors
and M3 inserts : https://fr.aliexpress.com/item/1005004535859664.html

On picture it's my proto, the switch is optionnal

Anet

A8

No

No

30