We do not recommend freezing Gatorade. Freezing doesn't affect the efficacy of the product, only its sensory attributes. More importantly, the content of the bottle may expand under frozen conditions resulting in distortion of the seal integrity of the plastic bottle.
Properly stored, unopened sports drinks will generally stay at best quality for about 12-18 months when stored at room temperature, although they will usually remain safe to drink after that. If unopened sports drinks develop an off odor, flavor or appearance, they should be discarded for quality purposes.