Gregory Hall wrote:

snip
Problem is I am not at all sure how to secure a conductor from "plus" to
"minus" with the cells to make a strong and long-lasting series
connection.
Is there some kind of conductive adhesive or conductive film that can be
used for this application? Larry, where are you when we need you (weak
humor)?



Use copper wire and solder it to the top and bottom's of the respective
batteries. The trick is to not get the battery ends too hot. Use one of
those fancy butane torches that have a tiny flame. They will melt and stick
the solder without harming the battery. Practice on a couple dead batteries
first to get your technique down. Use rosin core solder.


Our local "Batteries Plus" (USA) will weld tabs onto customer's batteries
for a small token payment ($2 last time I had a dozen done).

Michael