I was looking at this over on the C. Crane site, where they have a somewhat different photo.
It's interesting, but it's seems very likely from the description that they're using a rechargeable battery internally. Since it's evidently not replaceable, and at that price it's not Lithium, it becomes a question of whether it's a NiCad or NiMH. If it's NiCad, you probably only get 200 or 250 cycles max before it starts to die, and possibly a whole lot less.
I can't say I care for either- too many devices have failed on me.