I regret buying a prius

Far from it. In practice, from what I’ve been able to find, roughly 3% of original hybrid batteries have failed in the life of the car. Sure, the longer and more you drive it, the bigger the risk. But that is true for every part of every car, and there no indication that the hybrid batteries are any less reliable than other components. You’re much more likely, for example, to have your center screen go out than to have your hybrid battery fail.

On the contrary, the Prius is an exceptionally reliable used car in general, and I view paying $5000 for one over 3 years as a decent price.

 

3%? Where did you get that from?

 

I think I agree with the general reasoning, but like @JC91006, I'd like some kind of a citation for that 3% figure. With the zillions of Gen 1 and Gen 2 out there, I'd expect something higher than that but I'd be very surprised if it was over 10%.

 

From data I aggregated from individual user reports on True Delta and Prius Chat, as well as percentages on Consumer Reports. All told, I looked at between 400-500 posts and maintenance histories. I know it’s nowhere near the total number of people that bought a Prius, but I figured it counts as a fairly representative sample.

From what I found, 2nd generation Prius hybrid batteries typically last at least 9-10 years, and fail at a roughly 3% rate after that.

1st generation Prii had batteries with a failure rate of 5-10%, but the second generation batteries were better.

3rd gen Prius batteries had a statistically negligible failure rate when I figured all this out a couple years ago. I would imagine we’ll see what failure rates they have over the next few years, since their 10 year “safe period” is ending.

 

The Consumer Reports data that I remember came from April 2014 (also mentioned on PriusChat here). They had delayed the report until they had eleven and twelve year old Prii, because until then there had not been enough battery issues to generate meaningful statistics. They reported a failure rate of 4% by year 11, rising to 5% (or one in twenty) by year 12. That was for the original Gen 1 batteries.

I assume the rate does continue to increase with age; I don't expect to see many Prii at the 2050 antique auto show zipping around on their original batteries.

 

I would also agree that the failure rate likely increases with age, and probably increases exponentially at some point. So if you keep a Prius until the wheels fall off, and you repair everything that goes wrong during that time, I could agree that at some point, the hybrid battery is going to go out. But that’s assuming 20+ years of ownership, and the vast majority of people switch cars far before then. I believe the current median car age at end of life is between 12-13 years. So if, for example, we use a 1.5 exponential increase and say that the cumulative battery failure rate goes from 1% at 11 years old to 2% at 12 years to 3% at 13 years to 5% at 14 years to 7% at 15 years to 11% at 16 years to 17% at 17 years to 25% at 18 years to 38% at 19 years to 57% at 20 years, even then a majority of owners who had their cars for up to 19 years would never experience a hybrid battery failure. So the statement that a battery failure is inevitable would only be accurate for people who choose to keep driving the car far longer than average.

 

Can I buy your junkie unreliable battery ridden Prius please? Please send me a PM. I'll be glad to make you an offer

 

We really have no recent HV batt life data... we had the Consumer Reports, but since maybe MY2008 it seems like less failure rate, and it seems Gen3 was even better. But no data, just my impression. We lost our 06 HV batt this year at 192K miles and about 14 yrs. A while back we did some surveys here and we saw fairly high % fail reported. but not representative sample, and seems like better reliability since then.

 

The traction battery in my '06 Prius failed at around the 280,000km mark and roughly 13 yr old. The Taxi Prius ('08) at roughly the same age, but around 700,000kms. The taxi Prius would have definitely had a lot more deep cycles through the traction battery so cycling doesn't seem to be the problem ....... although having said that, the '06 Prius does have a 10kWh "plug in" separate battery that keeps topping up the traction battery until the plug in battery is drained to around the 210v mark (roughly 2.8v per cell, 76 cell in series LFP battery) These would have been very shallow cycles keeping the battery up around the 60% to 80% range (a guess really, so the green bars remained on the meter). The plug in battery could have been carrying a very tired traction battery and the actual failure was only apparent after we had been away for 6 weeks and the Prius was in the carport unused.
In both vehicles, a second hand battery was pick up from a vehicle dismantlers yard very cheap and both seem to be working well and have been for a while now.

T1 Terry

 

Use it or loose it

 

I haven't gotten that PM yet. I truly will buy your car.....I'm not just saying this.....

 

You don't sound serious about that regret

 

i understand the feeling... and i think it is just part of old car ownership in general not necessarily just the Prius. i have driven/had many old cars.. i have been stranded by a $3000 honda accord, and a $2000 jeep, and i saw all over the internet people saying things like 'my accord / jeep went to 300k miles, never had a problem'. of course they say those things on forums that are filled with people discussing their problems.