I have an application that's powered by a typical 3S LiPo battery pack and charged through an MPPT solar charger. The charging circuit in the link doesn't balance the battery pack, however, which means that I have to do it some other way. It's trivial enough to buy an off-the-shelf balancing circuit, but I need to be able to shut it off when not charging so that it doesn't drain the battery.
The question is this: given a standard xS LiPo battery pack, and access to the
CHRG pin off the charger (meaning a signal that goes high when charging), where do I need to interrupt the balancing plug to safely shut down an arbitrary external balancing circuit? Do I have to interrupt all x+1 lines, or can I just interrupt one of them?