Gravel Dropper Post with Di2

One of my gravel bikes is set up with 2x Shimano Di2. I’d like to add a dropper post. Couple questions… One is how to accommodate the Di2 battery in the setup. Are there dropper posts with built-in battery carrier (have not come across any), or does one simply drop the Di2 battery down the seat tube to the bottom bracket, and then place the seatpost? Secondly, since I am running 2x, can one program the accessory buttons on top off the drops to activate the dropper post? My other gravel bike is built with SRAM AXS - obviously much easier to integrate a dropper post with this setup as compared to Di2.

I have no input regarding di2 battery placement.
I will just point you to the Magura Vyron Elect dropper post, it is wireless. I use that on my gravel bike. The trigger can easily be placed in the drops, as it uses rubber bands.
I works quite well.
Note the I’m running 1x, but that placement should work with 2x.


I put the battery in the fork steerer tube on my MTB. The other option is the down tube, if you can get to that.

You would probably have to take out the fork, and push the battery in through the head tube… not ideal. Or indeed put it in the down tube through the bottom bracket.
Both are not that great, since you’d have to remove the cranks/BB or fork if you ever need to get to the battery.

My MTB frame/handlebar were not really made for internal Di2 routing, so I made a small hole in one of the spacers and routed the wire through that:

And no, the battery hasn’t fallen out the steerer tube yet ;-). It’s pretty secure!

(here’s more on that battery holder: Install the Di2 battery in the fork steerer)

2x, can one program the accessory buttons on top off the drops to activate the dropper post?

Not as far as I know :frowning:

Seems like Shimano need to make an electronically activated dropper post with an internal Di2 battery. An e-tube connector on the bottom would allow any Di2 bike an easy upgrade. Either configure the additional buttons in the levers or that useless left hand 1x shifter to control it…