Well the battery could be fused, that's one option. I must say that I've never seen a fuse in a solar garden light, which is the intended application.
The rating on the battery is 600 mah, but because of the chemistry it can source at least
twice the current (2C), or maybe more. At 1.3A the schottky would be getting warm I would think.
The interaction or effect on the solar panel itself though is still a mystery to me. Depending on the internal resistance, the solar panel itself could get really hot?
*********************************************************
O.K. got some posts while drafting up my own response, Thanks:
HarveyH42: yes the schottky diode is to prevent reverse flow from battery at night "only". I realize that doesn't help or preclude inserting the battery backwards.
crutschow: So yea, the battery voltage would always be less than the open circuit voltage of the panel, hadn't thought of it that way, thanks. The schottky diode should be O.K. I think, may just have to try it out (with safety precautions of course) to see.