I've built a few Li-ion 14.8v battery packs now and I am very happy with them. My question is why do I have two seperate leads coming from my packs "one for charging and the other for balancing" and the same packs for sale on battery websites only have the single lead. I built my packs to their specs with the NON-Equilibrium PCB and poly switch. Do I even need the seperate leads or should I build it like they do??? Maybe I'm just confused about what the PCB does. Thanks.