Let's assume I am going to build a Li-ion battery pack with 12 18650s, where I connect four cells together in parallel and then the three sets of four in series.
My understanding is that a BMS keeps an eye on the voltage and keeps it from going too high or too low. Thus, would I then use a BMS module that connects three batteries in a series, or would I need to have a BMS with 12 connections, including the cells that are connected in parallel.
TBH, I am not at that level yet, but just trying to understand the nuances of li-ion batteries before I get my hands dirty.