OP - I think you meed to change your terminology. The Volt doesn't use
kWh while charging, except for a small amount in efficiency losses, battery cooling, preconditioning, etc. Most of the electricity is just transferred
from the grid to the Volt's battery. I think you want to know how many kWh are transferred (& used) during a charging session, right?
The answer to your question though, is that there isn't a meter built into the Volt's information system. The best thing to do if you want to be transparent on your end is to install a meter. I don't think they're that expensive. Or if you're just using the 120V EVSE, maybe even a Kill A Watt
device will work for you.