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Is there a good rule of thumb to determine battery health?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Chuck., Mar 11, 2016.

  1. Chuck.

    Chuck. Former Honda Enzyte Driver

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    Of course, you can tear into the Prius, but can you get a good idea with a casual observation?

    I know that the Prius I almost bought bounced thru 7 of the 8 bars - definitely a dying pack.

    The one I bought tends to go thru 3 bars most of the time - ScanGauge says 55% - 72%, although it's been more on occasions.

    Hope someone might say something like this:
    • 2-3 bars - healthy
    • 4-5 bars - starting to fail
    • 6-7 bars - bad cells - bad
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    I'm not sure state of charge and health go hand-in-hand. Ours will typically be around 3/4 full. But fully warmed up and level road, or a lot of low speed maneuvering (say a parking lot) the car will willingly eat up the charge, running electric-only. It'll bounce tho, with more typical driving.

    This is 3rd gen tho, not sure how relevant.
     
  3. The Electric Me

    The Electric Me Go Speed Go!

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    If your parameters are "good idea" and "casual observation" then I'm going to say No.
    As a chemistry based component with no moving parts, I'm relatively convinced casual observation of the behavior of the operational battery state of Charge gauge within the Prius itself would be at best a poor tool.

    Which leads to more complicated tools of diagnosis, which would extend IMO beyond casual observation.