First, thank you @aulakiria for this amazing device and also big up to @rojitor for all these feedbacks, I read it carefully and it helps a lot !
So you just convinced me and I sent my money in the next second.
Now come the question of the battery. You advice to use 3S lipo for spot welding (with nickel) and 4S (and even more) for soldering. Am I right ?
So do I really need to buy different batteries (don't have 3S or 4S, only 5S, 6S) ?
What is your opinion about that ?