If you actually think commercially available battery packs are being produced in super high tech, super safe, quality-controlled factories by experts, you should try disassembling one.
You do not need millions of dollars of equipment to solder battery cells together. You probably need “expert” training, meaning, like, watching a YouTube video. This stuff is not complicated.
I didn’t know soldering vs welding could damage cells, thanks for that! The battery packs I’ve built are all made from cells that have threaded terminal posts, because I don’t have a laser welder (which as I understand it is the tool that gets used for this most often).
I stand by my point though, because a laser welder is not particularly expensive or exotic equipment, you can safely operate one in a garage, and you can learn to use one effectively with a little bit of practice.
Attitudes like “IT’S DANGEROUS DON’T EVEN TRY IT” are silly, and lead to people having unwarranted fear about really basic, easy-to-understand technology.
You do not need millions of dollars of equipment to solder battery cells together. You probably need “expert” training, meaning, like, watching a YouTube video. This stuff is not complicated.