SAE J1772 has a data pin, yes. It's how the car communicates rate-of-charge. The Supercharger uses a different plug, though, which I don't know anything about.

SAE J1772 has a data pin, yes. It's how the car communicates rate-of-charge. The Supercharger uses a different plug, though, which I don't know anything about. The voltage (440v) and speed indicate DC charging, which J1772 doesn't support. (The Leaf uses the CHAdeMO connector for DC charging)