Prototypes don't need to work as long as they teach you something. Here's v2:
Aluminum cans work great for bridging multiple batteries in the pack together, but not so well when conecting to a #Meshtastic node. Crimping just isn't reliable enough and the whole "dissimilar metals" is a problem for soldering.
But wrapping stripped wire around seems to work great. It seems to be holding up to the initial field testing.
If it pans out, next I'll have to figure out some way to attach the node to the batter holder so I'm not putting as much stress on the wires.