Easiest & Quickest method for Balancing Hybrid battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by meyouall, Sep 17, 2025 at 4:48 PM.

  1. meyouall

    meyouall Junior Member

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    I tried to find the answer through searching but failed.

    - Which balancing method can one use to easily and quickly (not days/weeks) balance hybrid battery pack after one or two cells are replaced?
    - I have seen videos of hybrid automotive where he uses 3 methods— Prolong charger, equalizer cables and the method with two bars (all + on one side and - on other). Unfortunately his Prolong charger isn’t available in the EU. The other two methods is equalizing, not balancing; right?
    - If you recommend some sort of grid charger, please mention its name and would it do the job all at once— meaning the whole pack or will have to do it per block/module?

    I get an error code which says that block 4 is weak. It could be one cell in that block or both cells, I haven’t checked it yet.

    The Prius concerned is from 2006. 330k km. Based in the Netherlands.

    Thank you!
     
    #1 meyouall, Sep 17, 2025 at 4:48 PM
  2. bisco

    bisco cookie crumbler

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    you should be able to find a grid charger like prolong available in the eu. or you can build one.
     
    #2 bisco, Sep 17, 2025 at 8:33 PM
    Brian1954 likes this.
  3. dolj

    dolj Senior Member

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    There is no such thing. Restoring a failed pack takes time. How much time? It depends on the extent to which the battery has degraded. A simple, straightforward reconditioning cycle based on time, with no indication of errors, takes five days with a grid charger, if you want to sleep while doing it. With no sleep, you might do it in three days. ;) It takes considerably longer using a one or four-channel NiMH hobby charger.
    Correct. It is a process that has demonstrated no measurable benefit, so it is a waste of time.
    You mean one or more cells within one or both modules in block 4, yes. Inevitably, you will need to replace one or both modules using a reasonably (if not perfectly) matched module. Matching the replacement module to the remaining existing modules (in terms of capacity) is the real secret to having a reliable repair.
     
    #3 dolj, Sep 17, 2025 at 11:59 PM
  4. meyouall

    meyouall Junior Member

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    Building one is out of the question. No experience!

    If you know a good one online, please share a link.
     
    #4 meyouall, Sep 18, 2025 at 4:29 PM
  5. meyouall

    meyouall Junior Member

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    - Do you know which charger can make the process shorter?

    - I thought as the builder of the prolong charger Jose would know very well what he is doing. Apparently not?!

    - See the attachment for the exact error code. If i’m not wrong each block contains two cells. If it says block 4 is weak then one or both of those cells are weak right?
     

    Attached Files:

    #5 meyouall, Sep 18, 2025 at 4:36 PM
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