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New Here. Buying Prius with a bad Hybrid battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by littlehandegan, Oct 13, 2014.

  1. JC91006

    JC91006 Senior Member

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    you and me both.
     
  2. littlehandegan

    littlehandegan Junior Member

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    Pretty excited as well.

    Getting my list of stuff to baseline the car.

    1.Sparkplugs
    2.Oil and Filter - (Mobil 1 5w-30 and OEM filter?)
    3.Sparkplugs
    4.Toyota WS trans fluid - 4 qts
    5. Air filter
    6.Serpantine belt???

    Any other items? (Had water pump done at 90K)
     
  3. GregP507

    GregP507 Senior Member

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    It may not be the whole battery. Chances are, only a few cells are bad and can be replaced. I believe that second-hand cells can be bought online for less than $20 each. There is a video on You Tube about how to test, replace and balance the cells. The hybrid battery may not be as good as new with this repair, but probably a good match with the rest of the car.
     
    #23 GregP507, Oct 14, 2014
    Last edited: Oct 14, 2014
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  4. SageBrush

    SageBrush Senior Member

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    I keep wondering if a small imitation of the battery made by a 3-D printer would have an audience of DIY'rs.
    By small I mean say 4 modules rather than 28.
    Just big enough to familiarize oneself with the wires and package.

    Even better of course would be close to full size, made from modules that are 1.2v rather than 7.2v. That would be safe, and allow us to play around with a multimeter.
     
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  5. JC91006

    JC91006 Senior Member

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    Yeah.....Hasbro has one for those that want to become doctors.....Operation!
     
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  6. littlehandegan

    littlehandegan Junior Member

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    I actually have a friend who hooks me up on Toyota OEM parts. He can get me an OEM battery for $2013.41. I think the Dorman will be my choice, but nice to have that option.
     
  7. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    If I could get an OEM battery for that price, I'd get that over the Dorman all day long.
     
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  8. JC91006

    JC91006 Senior Member

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    My opinion is that the new battery for $2013.41 is a much better deal.

    This battery will last approximately 8 year or more. Based on your car's low mileage (assuming the problem is really just the battery), it should last you easily til 200k miles. With a Dorman battery, although it has a 3 year warranty, there's really no telling how often it'll fail within the 3 years. The downtime, headaches, being stranded.....all will not be worthwhile.

    The best of all, if you decide to sell the car in 2 or 3 years later, it'll be worth a lot more money when the buyer knows you had a BRAND NEW battery from Toyota installed in 2014 vs. a rebuilt used battery. That alone can bring up the price of the car $1000.....the price difference of the new and rebuilt battery.
     
  9. GregP507

    GregP507 Senior Member

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    I'm not recommending anyone do this, but I might try to bypass the bad cells with a jumper-strip. The resulting battery should still take a full charge, albeit with slightly reduced capacity.
     
  10. exstudent

    exstudent Senior Member

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    From the information I have read about rebuilding the entire pack, something tells me this won't work, and its a bad idea.
    1 module = 7.2V; 1 module is made up of 6 cells; 7.2V/6cells = 1.2V/cell
    Working HV Battery: 28 modules x 7.2V = 201.6V
    You are proposing 27 modules x 7.2V = 194.4V + 6V (1 partial module made of 5cells x 1.2V=6V) = 200.4V OR 27modules x 7.2V=194.4V
    If I recall correctly, the HV ECU only allows .02V variance between module pairs. One bypassed cell (1.2V) or one bypassed module (7.2V), exceeds this threshold (.02V), and the final voltage of the pack is way off (201.6V vs 200.4V vs 194.4V).

    Besides, are you proposing to disassemble a module for this "jump?" In order to get to the module, you had to take out the HV battery pack. Why not just do the job right from the beginning? Also, can the modules be disassembled? Are these cells identical to the consumer grade retail cells? If one was wanting to replace the cells.
     
    #30 exstudent, Oct 16, 2014
    Last edited: Oct 16, 2014
  11. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    Yes, bypassing a module is not possible. First of all, the sensors will detect it and throw a code.
     
  12. vvillovv

    vvillovv Senior Member

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    I was gonna say, I think there is a priuschat member in NC somewhere that specializes in pack replacements. But I can't recall exactly who or where they are.
    I agree with usnavystgc and JC91006 about the OEM pack being better, since I think the Dorman is a used rebalanced pack and the OEM part is new.
    But definitely do your homework on what is available, your gonna have to anyway just to find a vendor to install it for you or even more homework if you are installing it yourself .
    It's not rocket science, but there is a lot of conflicting info on the net about how it's done, and figuring out which is the correct way before you start is really hard.
     
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  13. The Electric Me

    The Electric Me Go Speed Go!

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    Buying a used car is always a risk.

    But at that buy in price?

    Your risk is pretty much negated.

    Even investing $2000-$3000 into a new hybrid battery, you're ahead of the game. Then at the very least, you have a Prius...with a new Hybrid Battery.

    Assuming nothing else major is wrong? Good deal.

    If possible...I'd STILL probably want it checked out as thoroughly as possible. It's not the expected thing, you know about that could be the problem. It's the unknown problem that might be hidden that could destroy the economy of this deal.

    But on paper? Looks like a winner.
     
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  14. fileaudio

    fileaudio Member

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    Buy a used battery for 1200dlls on ebay. Check 12volts battery too sometines its the problem,ill buy that car no esitating
     
  15. littlehandegan

    littlehandegan Junior Member

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    Thanks. The guy who gets my parts is actually unable to ship it to me. I am leaning towards a Dorman battery. ($1,300 shipped)

    From the looks of Dormans DIY video, I will be able to tackle this job fairly easily in an afternoon (Less than an hour)
     
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  16. derekderek

    derekderek Junior Member

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    the dorman battery is a bad battery pulled from a car with 1 or more cells replaced with used cells from another battery. EXACTLY what you will get if you pull the battery, whip out the voltmeter and replace the bad cells yourself for 25 to 200 bucks. the remaining 1000 plus is for the warranty and profit.
     
  17. JC91006

    JC91006 Senior Member

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    There's much more to this process
     
  18. jdenenberg

    jdenenberg EE Professor

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    A little history on Dorman. Dave Taylor of Taylor Auto in NC started experimenting with these batteries several years ago. When he developed a full protocol (using carefully matched, young, low mileage modules) and custom charging/balancing equipment to refurbish the batteries, he launched ReInVolt (I have a ReInVolt in my 2004 Prius that is 3.5 years old - 67k miles). He successfully operated ReInVolt for several years with many satisfied customers (with a one year warranty on his rebuilds). He recently sold the business to Dorman, trained their staff, and remains active with the company. After analyzing the successful history of the ReInvolt installed base, their warranty is now 3 years. Dorman is a reliable source of rebuilt HV batteries. there are others, but you have to do your due diligence to determine the quality of their product.

    You do have other options:
    • Buy a salvaged HV battery - preferably recent vintage with low mileage from a cool climate. Then swap the modules into your existin HV battery preferably after load testing and balancing the purchased modules.
    • Have a good shop install a tested salvaged battery for you. The problem with this approach is that Gen2 HV batteries are at least 5 years old at this point.
    JeffD
     
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  19. H-lover

    H-lover New Member

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    May I ask ? about a prius 2004 140.000 km with a good condition battery and on time service oil,inverter recall and coolant etc ,what about battery life? Toyota says that the battery lives 15 years ?everything on my prius is good no problem
     
  20. valde3

    valde3 Senior Member

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    Battery life depends on lot of stuff. Age and kilometers/miles both mater. Terrain around where it’s driven will effect a lot. If its mountains battery gets to two and 8 bars a lot and will have shorter life. If your car sits for months battery may get damaged from that. If it hot then battery will wear quicker. You should use AC then because it will also cool the battery. And then luck has role in it also.

    Normally batteries will last around 300tkm 200,000 Mile Club | Page 23 | PriusChat but time maybe more residing factor here.

    If you want to longer the life of the battery then balancing it now maybe good idea. Traction Battery Preventative Maintenance - Hybrid Automotive Chargers | PriusChat or something else (you may even build your own).