[ondrasej]

This is definitely not a short-term solution, and it might not be practical even in mid-term, but wireless charging sounds like a perfect solution for this kind of environments.

The hospital rooms could have special "charging" spots on the floor/build into the furniture or just a hole in the wall. The patients would charge their devices simply by placing them on the charging spot/shelf. Now there are no potentially dangerous cables or plugs, and all charging can be done without devices leaving the patients' reach, reducing the risk of theft at the same time.

There's already an international standard for wireless charging. The only problem is that it works only with a couple of the current phones, and it's not very likely to appear in low-cost low-end devices that the patients of the mental hospitals most likely to use. But if it ever gets a wider adoption, this would solve a lot of problems...