UPDATE 20 October 2021: Here is another simple homebrew power supply that I use for my Internet connection during loadshedding. Simple but very effective.
Why would one need a battery power supply for the Raspberry Pi/AllStar Node? There can be many reasons. I needed a back-up battery power supply for one of my nodes that was running of a factory mains power supply. As a result of the load shedding (power failures) we experiencing lately and in future, I had to make a plan. All I needed to do was to connect the Pi to a 12v Power Supply with auto battery switching should the power fail. However the Pi runs of 5v. Back to the old "buck converter". Unfortunately there is no space in the 12v backup power supply so I had to come up with a cabinet for the buck converter. Scratching around I found two 40mm PVC end caps. I cut a small piece of 40mm PVC pipe, drill a few holes and added the end caps. I now have a project cabinet. It took me about 30 minutes to make and cost less than a commercial cabinet. Yes, it does not look good but it will be out of eye sight and it will function as planned. Here is a few images of the unit. It was installed today and now all the current GRHub Network nodes are running either of mains or battery power.
One day when I have a 3D Printer the problem with project cabinets will hopefully be solved.
