Hi all,
I have a problem that is repeating itself frequently.
I am working a lot with 18650 cells, and I assemble different packs.
Sometimes, after a while (within several weeks), one of the cells seems to be broken, to a voltage of 0V. So that brings trouble to the balance of the total pack.
It is not the CID (current interrupt device), because overall voltage of the pack is still intact. Meaning the other cells are getting to high in voltage to compensate the broken one.
I do use decent BMS modules on the packs, I do not believe this has anything to do with it. The cells that I use are NCR18650B (Panasonic), VTC5 (Sony), INR18650-30A (Samsung, a while ago). All these types had this issue sometimes.
My question is, can I discover that broken cell before I put the pack together?
It is very frustrating, it occurs very often recently, and cost a lot of money..
Thanks for your help!
Best regards,
John