Advice for hills (it works for my Insight):

Because discharging & then recharging the battery is an inherently inefficient process, it is better to use the power directly from the engine:

- downshift to 3rd when climbing (Second in a CVT)
- upshift to 5th when going downhill (Drive)
- keep the Instant MPG gauge above 70 mpg on flats (lean-burn)

That will keep your battery full, and avoid the waste of charging up later.