I just figured that being stretched to the end-of-travel and only gripping near the edge of the cell vs more towards the middle, was bending it outwards. Probably the shrinkwrap was acting juuuuust enough as a spacer to keep the relatively flat pad from making contact. The perfect storm of no-contact. :confounded:

Right now I got ’em going, and am taking care to not even breathe on the whole setup.

Fwiw, these are the blue-wrap LKs, not the black ones. Both tested to 3.6V almost exactly, within a few mV of each other. Both topped off at about the exact same time, and are running neck’n’neck in the discharge cycle right now. Nicely matched.

Well, at least this one pair. Still got the other to do.

Fully intend to pull ’em when charging back up to about 3.6V as well, vs topping off. Probably going back into storage unless I put a couple more F13s into rotation…