I have mechanical mods and I use them from time to time. Many of them are bare metal where the battery installs. For the most part, I have sets of
batteries just for the mechanicals. 21700s and 18650s. They have known characteristics. They are marked with markers. I also keep a good supply of wraps and positive side insulators for both types. lol It's good to be paranoid about batteries. The wraps are cheap. I would keep a supply of the positive insulators as well. I have had them split. It's super easy to rewrap them if you're unsure. Maybe 5 or 10 minutes work. Probably would not use electrical tape. If it heats up, the adhesive will melt, it's probably going to slide off the battery. Just my opinion.