Mine has a notch in the case for the Manual Batts as well. No
mod needed. And you can actually hold 2 carts, 1 batt, 1 atty + cart for a total of 3 carts, not 2. Also, I purchased a Car Lighter Adapter and Wall Charger that is USB compatible and bought 2 extra USB cables.
That was, if I stay at a hotel or something, and they don't have a USB port, I can still charge the PCC via wall outlet. And on long drives, I can charge the PCC case in the car. I got all my stuff sans the extra USB cables from RUYANDIRECT for a really cheap price. I got the USB cables from MONOPRICE for like 1.25 each or something. In total, I got all the accessories for my PCC (under $10). And BTW, the PCC at RUYANDIRECT is the one that has a notch for the MAN batt with no
mods. It's really cheap there, too.