Quote Originally Posted by Charlie View Post
... overheating is only a potential issue if you are charging a totally pancaked battery. In normal use you really don't need to worry.
What if the battery dies, sulfates, whatever?


The 317 is a bit light, but conceptually you could use it as a reference with a couple power transistors that turn on as required.

The circuit in the link seems fine.
I'm open to using higher rated components, I'm not merchandising. I try to follow his math on how to select resistors but I get lost.

Robert