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How to Change the HV Battery CELL / Module/s on Gen 1 Prius

Discussion in 'Generation 1 Prius Discussion' started by DRACO, Jan 12, 2016.

  1. H W Rosenmayer

    H W Rosenmayer New Member

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    Hi Guys, I'm working on reconditioning my Gen 1 HV battery and I can't get the last 5 silver bolts off so that I can get to the cells, any help or advice to get them out would be greatly appreciated!
     
  2. EddieAtl

    EddieAtl HYBRIDATL

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    Hi there, do you happen to know why all of the modules on my battery showing 10.5 volts?
    Also, any insight on best way to recharge these modules.

    Thank you

    Ed
     
  3. DRACO

    DRACO Member

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    Hey Ed,

    We need more information. Please post your read out so we can better assess what is going on with your battery.

    If all blocks are at 10.5 while car is on, then they may all be beyond the minimum threshold to hold a charge. But we need to see your read out.

    Jim

     
  4. blake9809

    blake9809 New Member

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    Where do you buy the gen 1 cells to swap out, ebay?

    i have seen people online selling or talking about buying a grid charger and charging their hybrid traction battery to full capacity and then discharging it to minimum to exercise the memory and get the cells back to great health. Are those chargers and procedure worth doing? Does it really make a difference? If so what charger and discharger do you recommend?
     
  5. DRACO

    DRACO Member

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    Hey Blake,

    Yes, the old eBay. Just make sure you test the voltage when they arrive to insure voltage has not dropped during shipping. If it does return it and buy in pairs to give your rebuild a chance.

    Example, the TIS will show a faulty bank, bank has two cells and only a tear down can you then determine which cell is faulty.

    I personally did not use the grid charger, I used the car itself to force charge and discharge several times to help equalize the SOC of the cells. It seems to work but the grid charging/discharging is better option if budget permits.

    Break a Leg, be Safe Please,

    Jim
     
  6. dolj

    dolj Senior Member

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    A small editorial notice about the terminology that is consistent with the terminology used in the repair manual, just to avoid misunderstanding or confusion.

    Techstream will show blocks which are pairs of modules. A module is a sealed unit that contains six cells.

    A Gen 1 has 19 blocks, 38 modules, or 228 cells.
     
  7. strawbrad

    strawbrad http://minnesotahybridbatteries.com

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    I have read through the problems you are having to keep the engine running. Why do you now suspect the battery that you just replaced? Are you getting battery codes? Do you know how to do a forced charge and discharge test on the battery?

    99% of original Gen 1 battery modules are now junk. I suspect the used battery you just bought was a factory replacement at some point. The battery modules have a date code. You can read this date code on a few of the modules by pulling the fan tube off the battery. The first two digits are the day, the third digit is the month with X,Y, and Z used for Oct, Nov, and Dec, the fourth digit is the year starting with A for 1999 and continuing from there. A serial number starting with 135L means the module was made May 13, 2010.

    Tracking down a P3191 engine failed to start code can be a bear. First to check is the MAF sensor. Be sure to clean the wires buried deep inside the top recess. A funky fuel pump can make the car seem possessed. The hybrid battery is NOT causing the engine no start problem.

    I am local to you and rebuild Prius batteries for a living. Feel free to call for help. My number is at the bottom of my post.

    Brad
     
  8. blake9809

    blake9809 New Member

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    oddly enough the replacement battery i purchased is a original with one red/white sticker on top but appears to be working extremely well :) i have a bad battery laying in my garage checking at 60V i wanted to rebuild that one and get it back up to perfect health.

    Also i do not know how to discharge or recharge a hybrid battery. I have been looking at the chargers online but look very expensive so i was trying to figure out cheaper options.
     
  9. CH1992

    CH1992 New Member

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    Thank you for the valuable information. Super extensive.
     
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