Internal Battery Charging Cable
The EW-EC300 Internal Battery Charging Cable is used to charge the newer Di2 series: Ultegra R8150 and DURA-ACE R9250. It charges the BT-DN300 Internal Battery through the charge port on the rear derailleur.
Also, it can charge the new power meters, FC-R9200-P and FC-R8100-P. It does not charge the older FC-R9100-P.
While the older SM-BCR2 charged the internal battery through the A Junction, the newer Di2 groupsets no longer feature any junction boxes. This functionality has moved to the rear derailleur and so have the charge port, status LEDs and buttons.
To charge you simply pop open the charge port cover on the rear derailleur and then attach the charger. The charger has a magnet built into and it should just snap onto the derailleur charge port automatically.
One end plugs into the rear derailleur and the other end is just a simple USB port.
Details & Specifications
|Shimano model number:||EW-EC300|
|E-Tube Port type:||None|
|Component series:||Non-series components NON (All)|