Color of the battery bars

1-2 bars pink, 3-6 bars blue, 7-8 bars green.

http://www.vassfamily.net/ToyotaPrius/

The Prius does not use the absolute full capacity of the batteries in order to prolong their life. Uses from 40% to 80%, where no bars is 40%, and all 8 bars green is 80%. The range of SOC for each bar is not linear, and there is hysteresis between bars.

In other words, low to high of say bar 2 is not the same as from low to high of bar 6. I believe bar 6 has the greatest range of SOC (State of Charge). Also, the threshold of going to say bar 5 to 6 is higher than going back down from 6 to 5. I suppose this is so the bars don't jump too much. The guess (gas) gauge is similar.

 

Run the car with the AC on while parked in READY mode. Soon you will see 2 pink bars.