Energy conservation strategies for electric vehicles on hills

Because the charge/discharge process of a battery is not perfectly efficient, there an optimal point before end downward slope at which battery-based electric vehicle can save energy by engaging neutral (i.e., coasting). As exercise in classical mechanics involving air and rolling resistance, we find analytical expression for this distance on constant slopes, together with saved. We compare solution to numerical solutions sinusoidal hills. However, considering characteristics current electrical vehicles, saved only few Wh per typical slope, resulting negligible gains any realistic trip.