The fire/etc safety is important and I have considered it before even working on the PIC code. I will have a mechanical, electricity independent solution. I'll have a small lever that will have to be turned 90 degrees to release the door.
If I want to create a charging solution, a circuit where, as suggested by someone, the batteries will power the system and will be charged constantly, what would such a circuit be? Any web pages?
Also, what is a filter cap and how does it work?
Thanks!!