External Battery

External Battery

Non-series components SM-BTR1

The Shimano SM-BTR1 is the Di2 external battery. While external battery mounts have changed over the years, the battery has stayed the same. The only external battery is still the SM-BTR1. Most bikes these days will be equipped with internal batteries such as the BT-DN110.

It weighs about 70g, has a rated capacity of 500 mAh / 3.7 WH and a rated voltage of 7.4 V. You charge the battery by taking it out of the bike and putting it in the SM-BCR1 external battery charger.

Affiliate Links

Using the affiliate links to purchase anything earns the site a small commission, at no additional cost to you.