About the battery...

First, hit the "Info" button. Depending on your car there should be several touch screen buttons. Hit the button that reads "Trip Info" and the Energy screen should come up, if it's the consumption screen,(the one with the bar graph) hit the button on the lower left that reads "Energy".

 

Springtime, you won't see an 80% or 100% charge! That would be hard on the High Voltage battery. The Prius was carefully designed to keep the HV battery in an optimum charge range, about 40% to 60%. The Battery image on the Energy screen is like a little window into the center of the full range of the battery charge.

I have the frequent experience of going down a long hill to my house and having the battery image go completely green. You know what happens after that? The Prius spins the ICE on and off to use the excess electricity in the battery, to reduce the charge to an optimum level. It wastes enegy to protect the HV battery.

The nice thing about the Prius HV battery management system (the battery has its own computer) is that you don't have to worry about it. It's smart enough to take care of itself. Just have fun driving, getting great milage, and producing fewer emissions.

 

Perhaps this enquiry is about the 12V battery. The car's computer system does not keep watch on the state of the 12V battery as many users know to their cost. Is there any way of checking how much power remains in your 12V battery?

 

Not that I read in the owners manual. I just took ownership of my 2006 Prius yesterday. I do have a question...in extreme cold when the car won't be driven for a day or 2, would it save the battery to put it in sleep mode? And would that also stop the smartkey from 'talking' to the car if the key is within the 5 meter range of the car?
Thanks for the tip about not needing to keep the hybrid battery in the 'green' range. Reading posts on here and messaging a couple owners convinced me to go with a prius as opposed to a camry.