Does the Prius have automatic cell balancing features?

Discussion in 'Generation 1 Prius Discussion' started by MArcin91t, Jul 3, 2026 at 4:50 PM.

  1. MArcin91t

    MArcin91t New Member

    Joined:
    Feb 27, 2026
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    Location:
    Poland, Poznań
    Vehicle:
    2000 Prius
    Model:
    I
    Recently, I've noticed that occasionally my Prius stops turning off the combustion engine and instead constantly charges the battery at a low current of around 5-8A (according to the Dr. Prius app), even though the LCD shows a full charge (and the Dr. Prius app shows 95% battery charge). I once had to drive about 35 km (18.5 mi), and after such a trip, the battery heated up to 52°C (125°F), even though the ambient temperature was around 15°C (59°F). Turning it off and on again disables this strange mode. I always thought the Prius didn't have a cell balancing function. Unless, of course, it's something else.

    Anticipating your question about battery health: Yes, my battery isn't in the best condition (delta V around 32%).
     
    #1 MArcin91t, Jul 3, 2026 at 4:50 PM
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Yes, that's totally a thing the gen 1 will sometimes do.

    My car did that HV battery rebalance thing again | PriusChat

    I may have freaked out the first time and interrupted it by turning the car off, but I later decided letting it complete what it's programmed to do was probably the better policy.
     
    #2 ChapmanF, Jul 3, 2026 at 6:17 PM
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