18650 is supposed to mean 18mm x 65.0mm?
Depends on who makes them. Thats a pretty good chart to follow to compare sizes. Most devices allow for the different tolerances.? It ultimately matters on who is making these. I've seen 18650s that were too fat to be reported sleeved or fit in a tube. I had one so long, I couldn't get it in my device and screw the bottom on. That was the early days though. The protection circuit was insanely janky. It was held on by a? single metal tab bent 90¡ã
Some devices won't accept flat styles at all. Like my head lamp. Its the way the battery bay is designed. The positive terminal is recessed slightly and won't make contact otherwise because of the plastic.?Anything annoying think is when flashlights bottom negative post dents the bottom of the battery.?
Jack of All Trades