Range decreases fast

congrats and welcome!

you're going bout it all wrong. hybrids aren't meant to overuse the battery. the battery is there to collect what would be wasted energy, then use it as necessary.

just drive it for a few tankfuls, and measure your mileage at the pump.

then, if you want to improve your mileage, learn how to drive a hybrid for higher mileage by searching youtube for instructional video's.
use search terms such as 'hypermile' and 'pulse and glide'. don't worry about km per tank or autonomy.

all the best!

 

Then you need a new battery.
Do you have any idea what you’re getting for mpg’s?

 

Sorry, but this is very confusing. Is it a 2012 or a 2017? Your post says 2017 but your profile says 2012.

Either way, leave that EV button alone. You're killing your mileage and reducing the lifespan of your traction battery. EV with a regular Prius is just so you can move the car a short distance without needing to start the engine. It's not meant to be driven in EV mode except in rare cases. Otherwise, just drive it and ignore the EV button. The computer will almost always decide when to start and stop the engine way better than we can.

It's normal for the battery level to have two unfilled bars. Like this picure provided by @john1701a:

That's where the car wants to maintain the charge. It may go up or down a little, but will always come back here.

 

i also liked ev mode so much, traded my hybrid for a plug in hybrid. the plug in charge lets me drive 12-15 miles around town, which is a lot of fun. when it runs out, it becomes a regular hybrid.

yours is too new to trade, but if you enjoy ev driving, consider some sort of plug in down the road.

 

Great advice, @bisco!!

 

Range to empty is based on your current driving style. If it says 520 km to start then you drive 20 km and it says 480 km, it just means you are not driving as economically as you were before it said 520 km.

 

...not just driving style of course, but terrain, weather, traffic etc all have an effect. So for example, you may have done 50 miles on flat ground, and then start climbing mountains - at which point you're going to see less mpg as the engine has to work harder.