Lets go with the usual reminder: de-soldering / soldering Li-ion cells can be super dangerous. With a bit too much of heat it can fire or even explode...
It doesn't quite explode. Instead it shoots out a super hot flame that is nearly impossible to put out.
Imagine having a blowtouch that you can't extinguish or touch which is likely rolling around.
Hobbyists should buy cells with pre-welded tabs. You solder onto the tabs, not the cell terminals.