Background: I have built a 2S 7.4V battery out of two 18650 batteries. I have some TP4056 (5V 1A Micro-USB) charging modules lying around. I would like to use these the TP4056 modules (one per 18650) to charge the batteries but from the information I've found, having any connection between the two batteries is not a good idea while charging.
Therefore, I'm looking for a switch that would only switch on one circuit at a time. Either the serial connection b/w the batteries, or the charging input to the TP4056s.
What exactly is such a switch called (if it exists)? Is there a more elegant solution to this?
Excuse my noobness.
With a DPDT switch (thanks @Solar Mike!), does the following circuit make sense?