Dr Prius App - Battery Life Expectancy - Purchasing 2008 Prius

Hoping you might be able to help me out.

Recently moved back from NYC to my parents in New England to ride out the rest of the pandemic. I'm looking to purchase a Used 2nd Gen Prius. The ones I've narrowed down are 2008s and 2009s. I'm trying to be thorough and run the VINs through CARFAX and the Toyota website to find out when parts have been replaced, at what mileage, etc.

I finally found one I really liked, and decided to go and see tonight. It's a 2008 and has around 144K miles around it. 1 owner.

The car is being stored outdoors at the dealership and as of late, the temps have dropped down into the 30s at night. When I went to visit, the temp was probably in the 40s.

It was my first time using the Dr. Prius app. I ran the Battery Life Expectancy Test as per the directions in the app. Step 3 (keeping the needle in the green) kept stopping, as it would suddenly say i was drawing too much electricity or not enough. Took around 7-10 minutes. So when it finished, it said that may have compromised the final reading, but I was looking at a Battery Life Expectancy of around 59% (FAIR).

FIRST QUESTION: Is a rating of 59% for a 2008 with 144K miles accurate/seem about right? And how long/many years will it be before needing to replace the battery?

I then drove the car for about 20 minutes. Very flat roads. 30mph sections and 50 mph sections. On the monitor, it said I was getting around 38/mpg.

SECOND QUESTION: Is 38/mpg due to the 59% life expectancy? Or the car not being warm enough? Or could it be from something else?


I took a couple of screen shots while I was driving. Just posting them here to see if everything seems normal for this 12 year old car.

EDIT: ALSO, the Pack Voltage square was in the red around 275 when i was driving. It was my first time using the app, but the red square felt ominous. Is this normal? What's the reason for it?

Let me know what you think.
Hoping to be a Prius owner soon!
Thanks