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will a new 12v save a failing hybrid battery?

Discussion in 'Gen 2 Prius Main Forum' started by Allen Wolfe, Jun 1, 2021.

  1. Allen Wolfe

    Allen Wolfe New Member

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    Over the years I have had professional replace individual cells in my hybrid battery as they have gone out. Everything was running fine, then someone stole my CAT converter, the 07 prius sat for too long and not it seems like my 12v is dead, but it might also be killing my hybrid battery.

    I got the loud fan noises after the new CAT was installed and am debating whether it is worth it to get the new 12v yellow top battery if it is going to help my hybrid cells not to die or is it too late and i am throwing good money at bad?
     
  2. PriusCamper

    PriusCamper Senior Member

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    For starters, Yellowtop are a fake 12v battery company that used to be great before they were sold off to a crime syndicate operating out of Mexico and if you have one you need to replace it with a real battery and file a complaint against them through all appropriate channels so they are banned from ever selling a 12v again.

    As for hybrid battery, you're lucky to have a mechanic that will replace modules and this is more of the same. Alternative is to replace whole pack with new for $1600 to $2000 and forget about hybrid battery issues for more than a decade.
     
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  3. meeder

    meeder Active Member

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    Yellowtop isn't a brand. Optima is the brand that produces Yellowtop spiral wound AGM batteries. Optima has been a part of Johnson Controls in 2000.
    Optima used to be Gylling Optima which was a Swedish company.
     
  4. sam spade 2

    sam spade 2 Senior Member

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    will a new 12v save a failing hybrid battery ?

    NO.
    But it might allow the computers to recognize that the hybrid battery is really NOT going bad.
     
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  5. PriusCamper

    PriusCamper Senior Member

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    When it was a Swedish Battery company they were known for quality... When they got bought out they were made super cheap and they re-sold rather than recycled the bad ones and the only thing the new owners kept for the Prius version is the distinct yellow top, which is why people commonly refer to it that way. As in yellow has a powerful psychological impact. For example I could empty out your garbage can and put it in a yellow garbage bag instead of a black or white one and most people would think the garbage in the yellow colored bag would be better garbage than the garbage in the white or black garbage bag. As in Optima batteries are made of garbage no matter what color they are.
     
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  6. meeder

    meeder Active Member

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    I never hear any negative reports on them overhere.
    The only thing is that they need 14.7V instead of 14.4V for best performance.
    It might also be that the Optima batteries we have here in Europe are prodiced in a different factory.
    I don't know if the rest of batteries made by Johnson Controls are just as bad?
     
  7. Allen Wolfe

    Allen Wolfe New Member

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    Thank you, it is more of a last resort for me. fingers crossed it helps.
     
  8. PriusCamper

    PriusCamper Senior Member

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    It's possible Europe has different standards/greater consumer protections laws so your Optima aren't trash like they are in US.