Housing options that support a bridged battery/extra battery?

It would be great if there where housing options that support the framework platform that accommodate a hotswappable battery, not unlike the t-series thinkpads of yesteryear (t480/t430/x230, etc). framework wouldn’t even have to sell the cells necessarily if they allowed a standard format like the 18650 cell, I imagine a tube/cavity where a user could just pop 6x18650 cells in like a flashlight and double or triple the battery life.
Relevant Links:

One way to to this is to have a battery pack that can connect over type-c through an expansion card. Type-c supports direct battery connection to the system which would allow high efficiency use, and I think we may support this. However we have not tested this, (it is hard to find batteries that connect the cells directly to the output) with the correct PD contract.
There would be some work required to prevent the external battery from charging the internal battery when connected.


This is exactly what I want!!! My current workhorse for field work is the Thinkpad X270. Having the combination internal battery with swappable external makes work so much easier when I might not have access to an outlet until I get back to the hotel, and I don’t have to worry about a battery that isn’t physically attached when I have to move around a bunch. When I am low on battery I just go over to my bag and grab another one that I have all charged up and swap them out.