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Gen II Prius HV battery dying at 78k?

Discussion in 'Gen 2 Prius Main Forum' started by tonymark, May 5, 2014.

  1. tonymark

    tonymark New Member

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    After the dealer having my car for a week, Toyota has finally agreed to offer a miniscule $750. I really can't blame them, my car is out of warranty. I guess the dealer must have padded out the quote they sent Toyota because the discounted price came out to $3000. I asked Toyota if they could discount just a new battery for me to install. No surprise, the answer was NO. Oh well, guess I will rebuilding it myself. Any online documents of threads anyone would like to recommend?

    Thanks for all the advice.
     
  2. ToyoWorks

    ToyoWorks New Member

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    I do anywhere from 3-4 battery repairs/rebuilds a week at my shop. I've seen them fail around 80k but the car was a 2004. What I'm starting to see is that it's not just mileage that can cause a failure but time, 8-10 years.this is just from my experience I could be wrong
     
  3. sorka

    sorka Active Member

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    Do you mean the ones you rebuild fail at around 80K. If you mean all original factory batteries fail at 80K. Most Prius HV batteries last far far longer than that. I have 170K on mine. 2fas4u(sp?) had like 590K miles on his before he traded it in on a gen III and it had the original battery.
     
  4. JC91006

    JC91006 Senior Member

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    This really depends how long you intend to keep your car. If you think you will keep it for another 8 years or more, a new battery from Toyota isn't a bad idea. Your car has low miles so it should easily go another 8 years (which will bring you to about 160k miles).

    A rebuilt battery will never be as reliable as a new battery. you may have to rebuild it several times to get another 8 years from it.
     
  5. Jim Porta

    Jim Porta Junior Member

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    I agree with ToyoWorks . My 06 Prius has 89,000 miles and the traction battery is swinging low to high charge more and more. I suspect you could get 200,000 plus miles in 8 to 10 years on the battery or less than 100,000 if you're a low mileage Prius driver like me. Time is a factor.
     
  6. sorka

    sorka Active Member

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    The majority of '04 (including the high mileage ones) still have their original traction battery. There's a light uptick in failure rates in climates where there are extreme high temperatures like Arizona.
     
  7. uart

    uart Senior Member

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    Yeah, these older Priuses (8 to 10 years) still probably have a lot of cycles (charge/discharge) on them, even if they don't have relatively high miles.

    What you find with lower mileage cars is that they've generally done just as many (often more) trips than high mileage ones, just much shorter trips. Cold starts tend to hammer the battery a bit (people often report rapid drop of SOC in the first few minutes), whereas long highway cruises tend not to work the battery very hard at all (provided it doesn't involve mountain passes). So it's probably not all that surprising that many lower mileage batteries are still aging similar to their higher mileage cousins.
     
  8. ToyoWorks

    ToyoWorks New Member

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    No it's not common to see a battery with that low of mileage to have a failure. My traction battery on my personal prius went out at 203k before needing a rebuild.my car is an 04"
     
  9. jeff652

    jeff652 Senior Member

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    It's harder on NiMh cells to sit unused than to be driven daily (or at least 5 days a week). Any car that sits for more than 2-3 days at a time is a perfect candidate for one of our grid charger's to easily keep the cells topped and balanced. It also works as a PHEV charger, although a slow one :)
     
  10. nh7o

    nh7o Off grid since 1980

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    What are the chemistry details of the cause of this? My '09 sits often for two weeks between trips. I see no drop in SOC over that length of time.
     
  11. ToyoWorks

    ToyoWorks New Member

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    Messages you very interested in more info on the charger
     
  12. jeff652

    jeff652 Senior Member

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    Well, I am a CPA by day, not a chemist, but there is some good info out there. Self-Discharge of NiMh cells is even worse in the low resistance NiMh cells used in our hybrid vehicles as they are designed to give their charge easily. When we stomp on the accelerator at a green light, we want power right away ;)

    Here's some reading that might help:
    Self-discharge - Wikipedia, the free encyclopedia
    and
    Nickel–metal hydride battery - Wikipedia, the free encyclopedia

    The reason you don't see a change on your dash SOC when re-starting the car is that the car does not recalibrate to the current charge level of the hybrid battery each time the car is powered on. The vehicle has no concept of elapsed time when powered off. You could turn the car off for 10 years, then turn it back on, and it would display the charge same level from when it was powered off 10 years ago even though the battery would effectively be at zero SOC.
     
  13. tonymark

    tonymark New Member

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    Okay the saga has ended. After Toyota HQ came back with goodwill warranty offer of $750 and my cost would still be $3000, I told the dealer I would come pick up my car (I was just going to rebuild the battery myself). Service employee told my he maybe could trim off some of the labor and extra costs. He came back with a final cost (with goodwill discount) of $2369 including tax. Can't really beat that price for a brand new HV battery installed by Toyota dealer. Since the car has relatively low mileage and I will keep it for several years, I took the offer and now have a brand new HV battery. Hats off to Chris Epps at World Toyota in Atlanta.
     
    uart likes this.
  14. uart

    uart Senior Member

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    Thanks for the update tonymark. Since you're planning on keeping the Prius for some time then I don't think you can beat going with a new battery. :)
     
  15. ssaylor

    ssaylor Junior Member

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    I have a CARB 06 purchased in CA, now in AZ. If I ever have a battery issue, for that $, it's going back to CA on a truck & be re-registered for the 10 year warranty.
     
  16. uart

    uart Senior Member

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    There you go, I fixed it for you. ;)