Installing new cells, 2011 Prius

Discussion in 'Gen 3 Prius Main Forum' started by Bill Frederick, Mar 6, 2026 at 4:16 PM.

  1. Bill Frederick

    Bill Frederick New Member

    Joined:
    Jun 11, 2025
    20
    7
    1
    Location:
    Illinois
    Vehicle:
    2011 Prius
    Model:
    N/A
    I’m installing new cells in my 2011 Prius. I do not have it back in the car yet but I’m curious if I put the cells in backwards does it matter? I’m having a hard time finding an answer online. The old cells I took out were not numbered or the numbers faded a long time ago. Attached is a picture. Thanks in advance for your help.
     

    Attached Files:

  2. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,784
    3,973
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    switch the positive and negative cable on a 12v battery...naaaa. it doesn't matter... :whistle:

    It does matter. But but putting new block in with old blocks is NEVER a good thing to do.

    You'll have to charge each block, then match 2 blocks that are closest to the other in voltage.
    Then you'll have to charge and discharge several times then a long charge to balance them out.

    Have fun playing wack a mole. (y):whistle:
     
  3. Bill Frederick

    Bill Frederick New Member

    Joined:
    Jun 11, 2025
    20
    7
    1
    Location:
    Illinois
    Vehicle:
    2011 Prius
    Model:
    N/A
     
  4. Bill Frederick

    Bill Frederick New Member

    Joined:
    Jun 11, 2025
    20
    7
    1
    Location:
    Illinois
    Vehicle:
    2011 Prius
    Model:
    N/A
    OK. Sorry I guess I wasn’t very clear. Of course I’m not gonna switch positive and negative. My question was I put the Cell marked number one in first and the Cell marked number 28 in last. I’ve replaced all 28 cells so they should all be charged properly. So long as all my positive and negatives are correct, does it matter if Cell number one goes in first or cell number 28 goes in first? That was my question.
     
  5. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,784
    3,973
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    That makes more sense.
    It doesn't matter what order they are in, or rather position.

    Since they are new, just put them in. After they are in, you can number them. Though you don't
    need too, it doesn't really matter. Only if you have an issue with a block you'll know where it is.

     
  6. Bill Frederick

    Bill Frederick New Member

    Joined:
    Jun 11, 2025
    20
    7
    1
    Location:
    Illinois
    Vehicle:
    2011 Prius
    Model:
    N/A
    Perfect!!! I appreciate your help. It’s pretty clear I’m new to working on hybrids. Thanks for making it easier for me
     
    bisco likes this.
  7. Hayslayer

    Hayslayer Active Member

    Joined:
    Nov 6, 2024
    456
    264
    0
    Location:
    USA
    Vehicle:
    2009 Prius
    Model:
    Touring
    Hi Bill,

    What do you mean by 'new' cells? Those are gen 3 battery modules right? I'm guessing these were bought as a set of 28 refurbished?
    The Gen 4 module had a different top design. I think those started in '16 or '17.
    There's a guy on ebay who is actually selling brand new modules designed off the Gen 1 module housing. The clips on top are rotated 90 degrees from where yours are. I know nothing about their manufacturing, and I haven't heard good nor bad about them yet. Very curious though.
    There's a few very reliable 'refurbishers' and MANY not so reliable. The stories I've heard.......the batteries I've seen......lol.
    I hope you got a good one!!
    Can you give us a serial number from the top of one of the modules?