The diameter of the biggest part, namely the camera head, is 23mm/0.9in. 

I have not looked for a specific travel case, but unless you are being really rough with it I would say a padded envelope or a generic small case would do it. It's pretty sturdy. I take it to to the office sometimes and just put it in one of the pockets of my laptop case. Also, for extra protection against scratches I never removed the clear plastic film that comes over the screen. Except for the red ""pull here"" tab, you can't tell it's there. 

If you use EN EL 15, you can use these batteries. But I'm not sure if your camera allows them to charge in camera 

Thank you for your question. This model no touch screen, but it can be easily operated by the buttons on the panel. 

this solar camera have 4X digital zoom.