For the poster that asked what does the screen look like when fully charged. Sorry for the fuzzy focus, I need to clean the lens on my iPhone.
I have a big steep downhill on my way to work. Often but not always, it charges up fully by the time I'm at the bottom. Then it discharges again over the next few km. Galaxy Nexus ? 2
During normal flat driving (or even running up/down hills in San Francisco) my C rarely (i.e. NEVER) hits full (to the top of the battery... NOT lighting up the terminals, like you asked about... they don't light up). Driving on my commute I encounter about a 4-5 mile declination out of some foothills. If I'm not speeding I can fill it up using light braking, using "B", AND/OR using very light throttle (anything except hammering the throttle). If you don't typically drive any lengthy downhill stretches where you are able to keep your right foot well out of the throttle, you'll probably never see it fill up.