By default, a fully-charged Accord PHEV starts in battery-only mode and can run battery-only at speeds up to 60 mph. The gasoline engine kicks in when the battery runs down, at high speeds, or if the electric motor needs help. A console button gives the driver options. A quick press shifts from EV to to hybrid. A longer press forcibly recharges the batteries. Normally this doesn’t make sense because it’s inefficient. But you might want battery power in reserve for climbing steep slopes ahead, or for silently creeping in the driveway late at night.
If you drive a lot, this might be a hybrid car worth looking at.