Visited on May 20 without charging.
The chargers are in UG2, but there are no directions. It's best to take the rightmost ticket gate, so you're aligned with the ramp down to UG2. I'm not sure that you can go back down to UG2. from UG1.
The chargers are at the bottom of the ramp to UG2.
The parking is open 24/7. There's a reader for the tickets next to the entrance on the side of the restaurant terrace to re-enter at night.