DI2 on S40

[James Lombardo]

My S40 is getting close to completion but there’s a question of where to mount the DI2 battery. Is there any kind of consensus on where to mount it? Anyone know of a build report with this detail on the web?
A search here resulted in these results:
Battery:

“I installed the BT-DN110 seat post battery inside the slider (wrapped in bubble tape so it won’t rattle).”


“In my case, the DI2 battery is located in the hole in the middle of the frame under the seat. “


“The battery is in the steering tube. I put in a piece of pipe insulation. It fits well, no problems. Be careful which battery you get. Only the newer battery has the brains that allow for the use of some of the advanced functions, such as synchroshift.”

 

[LarryOz]

Is there any kind of consensus on where to mount it?

When I installed di2 on my V20 years ago I mounted it in the slider, I think it is easy to run the wires to everything there than if it is in the seat

 

[OttoMatique]

I installed the battery into the bottom of the steering/crank tube facing down (forward). Taped soft foam pipe insulation around it to get a snug fit. The 4 way connector is below (in front of) the battery with the derailleur cables and the battery cable connected directly, and the connection to the head unit passes under the foam insulation. I drilled a small hole above the bottle cage holder screw holes to pass the connector to the head unit.