in a reverse enquiry kind of way, anyone know if you can charge the new internal battery with the PCME1 machine, possibly just need a micro usb-micro usb cable?
No, unfortunately. It uses a proprietary plug rather than either of those standards. Typical Shimano.. otherwise we could use a whole host of mini or micro USB chargers that are available.
Has anyone confirmed that you can add a 9070 rear derailleur to 6770 and it will support 11 speed?
This is a really good discussion / pictures on using the internal battery with Di2.http://glorycycles.blogspot.com/2013/03 ... rsion.html
They have this to say in the comments below:
"Something interesting that came out in looking into this again is
1. Shimano Ultegra Di2 Shifters work as 11 Speed with 9070 derailleurs and vi/vi 9070 Shifters work as 10 Speed with Ultegra Di2 derailleurs."
I would read that as you could do it, but it would require replacing both the front and rear derailleur. Which would make sense, since apparently the brains are in the FD. Feel free to correct me if anyone has more solid info (on a RD-only swap working).