Needed a simple light weight mount for my Meta Quest 3 headset - made a quick prototype in Fusion 360 that would fit a couple of compact round powerbanks . Walls are only 1 mm so intentionally very lightweight - expect the model can be scaled to fit different powerbanks - to make sure the battery does not roll out you could use a rubber band on the mount - potentially the design will be refined but works as intended. Works great printed with a 0.2 mm nozzle - because it is very thin no infill is required. Printed with a non-brand generic PLA on standard settings and that worked out great!
UPDATE
Included a version with 2 mm walls for increased robustness - both in a 0.20 and 0.16 nozzle size