CQ3 charging tips, problems and question

Discussion in 'Gen 3 Prius Technical Discussion' started by Seymour1, May 18, 2024.

  1. Seymour1

    Seymour1 Member

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    I have CQ3 chargers. I was getting some strange results in the recorded data. The charge and discharge readings would go up, way down and up again on the same modules. I could not tell a good module from a bad one. I felt that using alligator clips was not good. I then noticed that the banana plugs have a swivel in the end of the 4mm plug.

    I took my old bus bars and soldered the charger wires onto them and attached each bus bar to the screw studs on the modules. And, I soldered the swivel on the banana plugs to solder bridge the swivel.

    The CQ3 delta peak responds to a very small fraction of a volt. Thus, the connections must be consistent and solid from the charger to the battery modules. When measuring the discharge capacity, the amount of the previous charge is important. Sometimes, for some reason, (bad connections?) the charge did not reach the full amount (7500mah). If this happens, expect that the subsequent discharge reading to be reduced. And, due to the self-discharge nature of NiMH batteries, do not run a discharge/charge cycle, wait a day or two and then expect to get the highest discharge reading. I made that mistake.
    IMG_2681.JPG IMG_2678.JPG
    With good solid battery-charger connections, it seems that almost all of my charge cycles go to the maximum of 7500mah. Therefore, it does not go past the first cycle. I must monitor the charger and manually restart it for multiple cycles. The delta peak is set to default which is maybe too insensitive? Maybe the CQ3 is not detecting full charge or maybe all of my modules are faulty. Any ideas?
     
  2. 9Shenandoah

    9Shenandoah New Member

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    Having the same issue myself, always get the Capacity message. This is really slowing the process down.
     
  3. Tim22B

    Tim22B Junior Member

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    Same here. What did you come up with a solution, or did your soldering solution work?
    Please give us an update.
     
  4. bisco

    bisco cookie crumbler

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    Is gen 5 already having battery problems?
     
  5. Brian1954

    Brian1954 Senior Member

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    I reported this thread to the moderator and asked that it be removed to the Gen 3 forum. The OP owns a Gen 3 Prius.
     
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