A battery tray expander i created based on an earlier work by MandalloreNerfMods as a an in between step for another project.
This allows you to install a much larger lipo (+5cm battery tray) but it makes it impossible to screw on a barrel attachment as a downside.
For that reason I'm working on a version in which the barrel is connected to this piece directly and all are fastened with the same 3 screws.
Since there might be other people interested in simply adding a battery tray expander without an extra barrel I uploaded this fire separately.
Enjoy
For printing purposes there is a version in 2 parts in the files which will need much less supports. You can glue on the front piece afterwards