How to anticipate timing of battery replacement

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by gatorback, Nov 29, 2025 at 4:26 PM.

  1. gatorback

    gatorback New Member

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    2010 Prius
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    A 2010 Prius (90K Miles) was inherited: seems to be well maintained.

    I would like to know how I can electrically measure (or otherwise) the battery performance so I can anticipate / time the hybrid battery replacement.


    QUESTIONS
    ==========
    1) What is the lifespan of the battery in terms of shelf life / miles (cycles)?
    2) How to measure battery cycles?
    3) Have I provided enough information to anticipate a battery replacement? If not what else is needed?

    I would be interested in hearing from others that have:

    1) performed DIY battery replacement (link to battery please)
    2) replaced battery with a better spec (more charge / faster charge rate / etc.)
    3) replaced OEM equivalent at significantly better cost

    This video prompted me to anticipating battery replacement:

     
  2. Brian1954

    Brian1954 Senior Member

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    Use the Dr Prius app to get an idea of the health of the hybrid battery. Search for the website to learn more.
     
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  3. gatorback

    gatorback New Member

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    Thanks for the recommendation. Any "lessons-learned" from using the Dr. Prius App?
     
  4. bisco

    bisco cookie crumbler

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    it could last forever or throw a code tomorrow, there's no way to know.
    more importantly, you should look into the head gasket/egr problem, and the brake actuator. then decide how you want to proceed.
     
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  5. Brian1954

    Brian1954 Senior Member

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    I have learned that the hybrid battery in my 2011 Prius is in good condition for its age. I have been using Hybrid Automotive's Prolong charger and discharger, once per year, for the last four years to recondition the battery.
     
    #5 Brian1954, Nov 29, 2025 at 8:15 PM
    Last edited: Nov 29, 2025 at 9:15 PM
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  6. gatorback

    gatorback New Member

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    I'd like to understand the electrochemical issue that the HA-Prolong Charger / Discharger and the approach it takes. Is there anywhere that discuss the theory in-depth?
     
  7. Brian1954

    Brian1954 Senior Member

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    Search Hybrid Automotive and read the material on their website.