My 2011 Evora NA had the same hose but did not have the white end on it. It too was not connected to anything. Purchased both cars brand new and have the same Interstate battery. Is the Interstate battery not OEM?
Or the Interstate may still need a vent line and it was never connected. The OEM Varta had a vent on the very left side of the battery, and some genius made those vent tubes just barely long enough to reach the Varta vent. The Interstate probably has a vent in the middle, whereby the tube is too short. Make sure someone wasn't lazy and just didn't bother to hook up the tube because it was too short. You can get a prepackaged "kit" at an Interstate dealer (or call Interstate customer service) or a connector and additional tubing at any auto parts store.
Agree; Interstate battery has a vent port in middle of the long dimension. Should be connected to vent tube running out the bottom of engine compartment. I would not like gases expeled into enclosed trunk/battery box with vent unconnected. Interstate will give you the right angle fitting for the battery. It has an oval mating opening to fit the battery vent port (oval).