Buying used, how low is too low for Dr. Prius life expectancy?

i doubt anyone can tell you. driving a lot is a good thing for the battery, especially highway.
have you priced replacement batteries yet?

 

The lower the percentage, the more often the capacity will need to be restored. 40% left = every ~12 months. 70% left = every ~3 years.
Whatever Prius you buy, I would restore the capacity in the hybrid battery and change the busbars and nuts, cleaning everything first.

 

Move on to gen 4 and avoid the egr cleaning club fees.

 

And replace the head gasket one more time.

 

This was mine five years ago.
I've changed it a month ago. No error messages, no lights in dashboard but simptoms were quick charge/discharge and a couple of times I saw it at zero bars instead two minimum.
But as usual YMMV.

 

I can't offer any advice on how to read or interpret Dr. Prius findings.

If I were trying to get 150k miles out of a Prius over the next 5 years, I'd want that battery to be no more than 12 years old at retirement, or 7 years old today.

I think you should shop for a 2017+ car for a good chance of success in getting to your chosen goal on the original battery without drama.

Alternately, get an older one and make certain you can afford another $2500-3000 for battery replacement- prices vary.

 

That's not a good way to measure battery health... Voltage difference between blocks during high amp loads is a way better way to do it. As in you can deep cycle a NiMH at 53% and restore it up to as high as 98% via Maxx Volts or Hybrid Automotive products or build your own rig.

However if the voltage difference is too high under high amp loads, only replacing the bad modules will fix that.

 

Dr Prius had my battery at 48% over 2 years ago. Getting ~36MPG in city still, no sign yet of the battery dying.

 

Start your Prius in the morning and drive it right away without letting the engine charge the HB and see how many bars remain on the display from the charge.

 

Very myopic perspective; with 3rd Gen the hybrid battery could be the least of your problems.

 

Without letting it charge? I don't get it, is this a thing to let it charge the battery before driving?

 

Normally... but to check the remaining capacity in the battery, you need to start it and immediately drive until the charge level on the dash is updated (up to a minute).
A battery pack that has not lost its capacity, its charge will remain the same as it was at the start or may drop by 1 bar.

 

Sometimes if not most of the time, those head gasket issues are due to a degenerate battery that's failing and making that engine work extra hard to keep the current flowing to power the car. Both need to be top shape if he's going to get that many more miles out of it.

 

Dr pruis I have the app. I believe it's most of a guide that a 100% accurate.
I got a rebuilt battery 4 months ago. I suspect the battery is getting weak. Dr prius
I do believe the way my mpg it. It's kinda true. The place is got the battery from is big company 1 yr warranty.
But as oem toyota parts. You should buy a new one. I got avg old car with 217k on it. Only reason I got rebuilt $1000. As 1 year is good for me. If you have a cream puff. Get new.

 

Well, you've seen a measurement of 85% on an app...

What happens if the car doesn't actually drive like an 85% battery? I think it's pretty reasonable to doubt the remaining utility of a 12 year old Prius battery within the context of your mission goal, 150k miles over 5 years.

If you can't hack something like a 2017, I'd split the work across two cars. Roll the dice on a 2015, drive it for two years / 60k miles. Give it the maintenance it requires and not a penny more. Then swap up to a 2017-2020 for the other 90k miles.

If you ride the next one until the wheels fall off, the cost to get back in the saddle will feel even higher.