I have assembled my firts 18650 pack, however I am facing some issues with it. Before assembling it, I measured all the cells voltage and they were around 4.12V, however, after having connected all the batteries in a 4s3p configuration, when I measure the pack voltage it is at 14.2V and the cells are at 3.56V and the BMS is therefore cutting the battery. If I measure the voltage of the parallel packs(from possitive to negative on each cell), the voltage measured is again 4.12V.
Any idea of what is happening here? Is there any problem in the connections or I just have to charge the complete pack? Since the individual cells were fully charged, I am afraid of over charging it.