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Alternative AGM 12 volt battery replacement

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by vertex, Aug 5, 2013.

  1. vertex

    vertex Active Member

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    Four years ago I posted about the lawn mower battery I used to replace my dead 12 volt battery.
    Battery Replacement - Economy Method | PriusChat
    That battery was dying, only hold charge for a few days, so it was time to replace it. I looked around, and found an AGM battery Power Sonic PS-12350 NB that I picked up on Ebay from www.ecomelectronics.com for $67.50 including shipping. This battery is the same technology as the OEM, with the same capacity as the Yellow Top, 35 AH. I reused the terminal modifications I made on the lawn mower battery and the battery holder. You can see the new battery and the old one below as well as the battery mounting bracket. If you order from ecomelectronics use discount code SLA10 for 10% off. The standoffs on the battery bracket are schedule 40 pipe 3/4" held with electrical tape. The tape is just needed for assembly, the pipe won't move once it is tightened up. (Be careful not to over do it and crack the battery case.) On the plus terminal, I removed the post clamp that grabs the terminal, and used the mounting hole to bolt the terminal to the adapter pictured below.
    Prius Battery 001.JPG
    Prius Battery 003.JPG
     
  2. bisco

    bisco cookie crumbler

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    does it have a vent?
     
  3. vertex

    vertex Active Member

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    no ventless
     
  4. SteveLee

    SteveLee Active Member

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    Alternatives to the typical overpriced options for this application make sense. Each user must decide if the vent tube is worth $100. The general subject is very well addressed in this thread by John. Fitting mobility 12volt AGM battery. | PriusChat
     
  5. uart

    uart Senior Member

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    I recently replaced my original battery (8.5 years old!) with a cheap non oem part. See: Finally replaced my 8.5 year old 12V battery! Non AGM??? | PriusChat

    The one I used is vented and very well sealed, but not AGM. After looking very closely at how the ducting and venting works in the back hatch there, I'm not sure that the vent tube actually does much. Maybe it's needed in the event of a failure of either the battery or charging system.

    If you look closely at the ducting from the traction battery to where it vents out in the wheel arch near the 12V battery, you'll see that the ducting is not fully enclosed, but actually has a big cut away just near the 12V battery. (The opening is on the underside of the duct btw). So essentially that whole little air space where the 12 volt battery sits is vented to the exterior, while at the same time is at least somewhat isolate isolated from cabin space by the plastic covers that clip on top.
     
  6. vertex

    vertex Active Member

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    Uart, that is correct. There is a little tube that was for the overflow from the battery between the battery and the wheel well. The problem is the vent only does something when the fan is on in the battery pack.