No, I don't like the DC-DC, too much hardware, not enough energy. That is sweet! But I'm targeting 8-10kwh, which means I'll need 40Ah, I'm thinking I'll split the 4-pack into two 40ah each. That means I now only need to add 43-40ah cells, where I would have needed ~60 before. Now onto the fun stuff, how do I build a battery management and PHEV filtering pass-through ECU?