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dormant traction battery question

Discussion in 'Gen 2 Prius Technical Discussion' started by donzoh1, Jan 14, 2021.

  1. donzoh1

    donzoh1 Active Member

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    I got a traction battery for a Gen 2 from a junkyard maybe 6 to 9 months ago. I believe the battery is OK but have not yet measured voltage or anything. I plan to do that. Is there potential damage that can be done to the car or to the battery by installing this as is?
     
  2. Aaron Vitolins

    Aaron Vitolins Senior Member

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    It could be fine, but it could also could have some dead cells, especially if it sat for a long time before you got it. It’s just a gamble, I’d try and see what happens.
     
  3. PriusCamper

    PriusCamper Senior Member

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    NiMH batteries self discharge... So getting some hobby chargers like these: iMAX B6 V2 Charger and charging up each individual module is going to be the start of your journey with ensuring you have a healthy pack on the shelf ready to help you or your friends.

    Learning about load testing and reconditioning will be the next step after this.
     
  4. 2k1Toaster

    2k1Toaster Brand New Prius Batteries

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    If your time is free, go for it. Welcome to the world of whack-a-mole.
     
  5. PriusCamper

    PriusCamper Senior Member

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    Once you get good at it, there's very little surprise of bad modules vs. good modules as in no moles to wack if you can find all the bad ones before you put back together the pack.
     
  6. 2k1Toaster

    2k1Toaster Brand New Prius Batteries

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    Someone who is not starting a business but just repairing their vehicle will have very limited experience. Picking like modules and balancing the pack will most likely not be learned on the first attempt. And even then after all that work, you still have a used pack with maybe 15% to 30% of its usable capacity. For a grocery runner, perfectly fine. For a car that is driven every day for hundreds of miles, also fine. For most people, not so fine.
     
  7. mr_guy_mann

    mr_guy_mann Senior Member

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    Yes, those few words make a big difference to most people.
    It's EASY, once you have experience and know exactly what to do.

    Posted via the PriusChat mobile app.
     
  8. PriusCamper

    PriusCamper Senior Member

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    Not really... Some packs have limited capacity after a full rebuild and lots of reconditioning but that's the exception not the rule... In most cases restoring capacity to 96% of brand new is what happens, especially in the early stages when you're only replacing the first bad module. And if you have expensive lab grade testing equipment, which I don't have, offering a 3 year warranty is a viable business plan. I can't do that with my limited amount of equipment.

    But I get it... From your perspective, you're on here to sell your brand new alternative battery packs and your opinion on rebuilding packs or same price as you OEM packs, or use of lithium alternatives like Dr. Prius will always be negative to you no matter what because you got a business to run/product to sell. Nothing wrong with that bias... Makes sense to me...
     
  9. PriusCamper

    PriusCamper Senior Member

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    And life is way, way more rewarding when you take on challenges... Always makes me so happy when people with no experience come on here with a bad pack and they fix it themselves and their only expense is $30 for a replacement module and $100 for a couple-few hobby chargers.
     
  10. rjparker

    rjparker Tu Humilde Sirviente

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    First, the used gen2 hv battery is unlikely to cause damage to your car by installing it as is.

    However the "newest" gen2 battery is now at least twelve years old and could be seventeen years old. Like dog years, battery years can be hard on a guy. If the battery sat around for any length of time at the junk yard, the remaining voltage may be extremely low. Still it is worth a shot if yours won't run.

    Toyota and many of us believe the best hv battery solution is new cells. Primarily because most of are not hybrid battery hobbyists who enjoy the challenge of dealing with the problem over and over to save money.

    Which almost always happens when trying to make worn battery cells work.

    Of course if you want to get it up and running and its not a daily driver or it will be sold soon, putting a more permanent repair in place may not make sense. But I would not suggest someone has bias just because they advocate reliability over a shorter term solution.

    But given you have a pack at your disposal, I would certainly try it.
     
  11. 2k1Toaster

    2k1Toaster Brand New Prius Batteries

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    Not really. There are things that change inside a NiMH module moreso than just the capacity. The electrolyte doesn't go anywhere (hopefully) but the crystalline structures do change over time as well as the anode and cathodes themselves. You cannot repair those. A reconditioned pack will not last the same as a new pack. And it is very common for a reconditioned to capacity pack to have more failures due to something else other than capacity. We know in the Prius the car doesn't really care about capacity until it effects the swing of the cells which seems to happen in the 10% to 15% of capacity range.

    I have already developed a test lithium battery and worked with the car's ECU. It is NOT SAFE to install a lithium pack into the Gen2 or Gen3 Prius without ECU modification. On the Gen2 it is very easy to make a new ECU that is safe for under $60 in parts that is 100% backwards compatible. It is much harder on the Gen3, and I don't have one, but it should be doable.

    As for my packs I don't try to hawk them. The chicken and egg is I had to develop my packs because there wasn't a good solution to getting a new pack. Reconditioning is not a good solution. It hasn't been for 6 to 7 years now at best.
     
  12. PriusCamper

    PriusCamper Senior Member

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    --A "solution" is relative to what you can afford. If you can only afford a few hundred dollars in car repair then rebuilding is your only option. Most people are too poor to afford more than that, especially Gen2 Prius owners who are annoyingly frugal to the point of being irresponsible.

    --Reconditioning has always been a basic maintenance procedure for all Nickel based batteries and for a 1/2 century it's proven to work. Just because Toyota built their packs to still work on 50% lost capacity and they refuse to follow the established science of reconditioning Nickel batteries doesn't make them right, just more wasteful and exploitive of their customers.

    --A NiMH pack looses electrolyte through venting, or as I experienced with discharging Bumble Bee Battery sticks exploding where the cells connect to each other. You can actually measure how much electrolyte has been lost by a measuring how much a Prius module weighs. Haven't got into that yet, but plan too.

    --Lithium packs if properly designed are completely safe without ECU modification. For six years Dr. Prius has been refining his efforts and in hot weather testing vehicles even in 120' F weather have had no issue and I've also had one of his Lithium packs for winter testing in my car since mid-October also with no issue or concerns yet. Time will tell... I love how EV mode in my gen2 can be used for several miles and battery charge never drops below 5bars. That's way more than what Nickel can do. Also a Lithium pack charging is incredibly efficient with very little energy lost as heat compared to NiMH.

    --Nothing wrong with you selling your product on here. I'd actually be willing to help you as it's a good option for some, just let me know which link on here you'd like people to see first when it comes to considering that option and I'll make sure to use it more often when I reply to others who need advice.
     
  13. AzusaPrius

    AzusaPrius Senior Member

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    Hey I am one of those noobs that joined the forum and then my pack went bad and I fixed it for $25 for one module. I did not need a new pack but I have to say Dr. Prius Lithium battery pack is safe and is much lighter than OEM packs.

    Never touching or owning a prius before I can say I have learned a lot from this forum.

    Posted via the PriusChat mobile app.
     
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  14. PriusCamper

    PriusCamper Senior Member

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    How's your Lithium pack going? Any torture tests in super cold weather? I'm currently studying a slight reduction in MPG between NiMH and Lithium with Dr. Prius guy. But thus far it seems to be specific in my vehicle not in others.
     
  15. AzusaPrius

    AzusaPrius Senior Member

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    All is well with it and the temps get really low like 32F in the mornings.

    Have not seen it drop past two bars since the only time I got it to drop to two bars on the 15N Freeway.

    Permanent code erased on its own recently too.

    Posted via the PriusChat mobile app.
     
  16. mr_guy_mann

    mr_guy_mann Senior Member

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    Hey, if you have the time, the correct attitude (and a little aptitude), a bit of common sense, the time, and realistic expectations then I say go for it. I sure did, but I am prepared for the eventual repeat failure. Must say that the 2006 is growing on me. Don't know how I will handle it- repair again or just get a new pack? Hmmmm.

    Posted via the PriusChat mobile app.
     
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  17. donzoh1

    donzoh1 Active Member

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    Thanks for the responses here. I may have not mentioned this but the existing pack is working so I may just leave it. I am only getting around 38 mpg but it's cold here in KC so I think that may have something to do with it.
     
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