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Is there a way to test an old traction battery?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by elendilmir, May 11, 2010.

  1. elendilmir

    elendilmir Member

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    There seems to be no way to test the "healthyness" of a traction battery. Is there a way to test one for impending trouble? My '02 battery has been a trooper, with 110K to it's credit, but I would love to be able to know that it is getting weak. It would give me time to get to ReInvolt for a replacement.
     
    #1 elendilmir, May 11, 2010
  2. uart

    uart Senior Member

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    The following are good indicators

    1. Can it still use EV mode without the state of charge dropping extremely quickly?

    2. Can it still regen-brake without the state of charge rising extremely quickly?
     
    #2 uart, May 11, 2010
  3. elendilmir

    elendilmir Member

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    Happily the answer to both is yes. And I'm pulling in 45 mpg in the Maryland hills to boot. However it seems to me that in a world where a computer can diagnose my IGNITION COIL, there should be a test for general battery health. I've decided to try to become a member of the 200K mile club, and that will necessitate a battery, but I want to wring every mile that I can out of it. It just seems that there should be a better way.
     
    #3 elendilmir, May 11, 2010
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The Toyota diagnostics provide only a pass - fail status. You had mentioned the spark igniters as an example. Note that the diagnostics will not predict a future failure.

    My guess is that Toyota doesn't want owners whose traction battery is 2% above some "minimum" status to bug their dealer for a warranty replacement. Recall that their official stance is that the battery should last for the vehicle life. However "vehicle life" is an undefined term, and Toyota's idea of vehicle life might be shorter than your idea.
     
    #4 Patrick Wong, May 11, 2010
  5. 2009Prius

    2009Prius A Wimpy DIYer

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    Scangauge has an item that shows the difference among cells. I think a good healthy battery has zero difference but don't know at what number the battery is considered sick. As Patrick said there is a vague region between "good" and "dead".
     
    #5 2009Prius, May 12, 2010
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