Range names must start with a letter, underscore, or backslash. Following characters must be letters or numbers, periods, or underscores. You cannot use spaces or any character combination that looks like a cell reference.
You can create a range name up to 255 characters, but you won’t want to make it that long as it will be heard to read. I highly recommend using the following tips about creating names with Upper/Lower case, using a major/minor naming convention, and using range name prefixes.
Related content are,