SM-BTR2
Brand: Shimano
The first internal Di2 battery, slid into the seatpost or frame. Shimano quotes 500 mAh at 7.4 V for 50 g, charging in about 1.5 hours from a USB mains adapter — 3 hours from a computer USB port — through the SM-BCR2 charger plugged into junction A, without removing the battery. It connects through a single E-Tube SD50 port and was replaced in the catalogue by the BT-DN110 in 2017.
| Type | Electronic shifting accessory |
|---|---|
| Model years | 2013–2017 |