Just made a 4S BMS and it just started smoking??? Can I still use these batteries?
So I've been working on this BMS for a few weeks now using online research (it's my first time making a battery pack myself, also I didn't use any AI) and so far it's been going well. I haven't got access to a spot welder so I used these cheap amazon cases to solder them. The wires on them were kinda thin so I used some UK mains cable I had lying around for the main series connection and the thin ones for balancing. However, there were no solder points on the cases, so I had to kind of wedge the wire ends into the spring and the other contact. I charged all the batteries to ~4.25V with a "smart" charger I got on ebay. The batteries were of course all connected to the BMS board which I also found online, and the output of the BMS was connected to a buck converter which is activated by a switch I added.
I tried it out last night when the batteries weren't all at 100% and it worked fine without issues. But when I connected them up today and flipped the switch, smoke started coming from all the case joints, so I turned the circuit back off.
Anyone have any idea how to fix this issue? I know it's probably the shoddy case joints, but do I need to buy new solderable cases? and can I still use these batteries? They seem to be fine now.
P.S. this is my first reddit post, am I in the right place? also please don't clown on me too much for my ass setup