Fixable?

[u/_beef_cake]

I tried charging and realized it wasn’t because the + is concaved in.

[u/Darkest_HourEDC]

If you can get in there with a pair of strong tweezers or pliers you should be able to just bend it back into usable shape. The tweezers was recommended to me by Simon from convoy.

Keep in mind, if you damage the insulating ring or wrap in the process then you would want to replace the damaged insulation specially at the positive end of a cell

[u/iamlucky13 → u/Darkest_HourEDC]

Keep in mind, if you damage the insulating ring or wrap in the process...

This part is very important.

If you damage the wrap or the insulating ring around the positive terminal, it is possible to short the positive to negative, which can create a fire risk.

The cutaway image at the top of the following link shows this.

https://www.electricbike.com/inside-18650-cell/

The contrast could be better, but in the middle top, we're seeing the positive terminal. It's legs are squeezed against the current interrupt device by a plastic insulator (translucent white-ish in this case), which prevents the positive terminal from contacting the casing for the rest of the battery. The entirety of this casing is effectively the negative terminal. Without the insulating ring around the positive terminal, and the battery wrap surrounding most of the case, there's only 2-3mm of air standing between the positive terminal, and accidentally shorting to negative with your tweezers or pliers.

It can be done, but pay attention to what you're doing.

[u/Darkest_HourEDC → u/iamlucky13]

Thank you for hitting those points, i realize it was irresponsible of me not to elaborate on those details, when there could be people that read this and don’t understand proper safety around Li-ion cells.