1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Lifespan for 12v battery?

Discussion in 'Gen 2 Prius Technical Discussion' started by Bob Allen, Jul 30, 2007.

  1. Bob Allen

    Bob Allen Captainbaba

    Joined:
    Jan 16, 2004
    1,273
    11
    0
    Location:
    Seattle, WA
    Vehicle:
    2004 Prius
    I understand that the 12v battery in the Prius is different from a standard 12v; smaller and more like a motorcycle battery. I have 34k on my 2004 with no battery problems, but I was wondering what the normal life cycle would be based on the experience of my fellow Priuschatters.....and to avoid having the dealer push me to buy a battery I may not need.
    Thanks
    p.s.......what is the replacement cost for the 12v?
     
  2. efusco

    efusco Moderator Emeritus
    Staff Member

    Joined:
    Nov 26, 2003
    19,891
    1,193
    9
    Location:
    Nixa, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    They should be able to check it like any other battery. Mine checked out fine at my 60k inspection and I've had no issues. I'll replace it when it dies.
     
  3. KD6HDX

    KD6HDX New Member

    Joined:
    Oct 30, 2005
    256
    4
    0
    Location:
    Chino Hills,CA
    Vehicle:
    2005 Prius
    I am getting ready to replace mine very soon. I have an 05 with 64K miles. After reading all of the strange behavior posts that end up being 12V battery problems, It seems to me that the prudent thing would be to just replace it at the two year mark. The plus side for me is that I will be able to use the small 12V battery from my car to use in my jump kit for amateur radio emergencies. I think the battery will last a couple of years beyond 2 if I keep it on a trickle charger in my Ham shack (radio room). Even though we have AAA roadside assistance, I do not want to chance having my wife experience glitches with the car when she drives it alone.
     
  4. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,985
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    In hot climates lead acid batteries tend to fail after 3-4 years. In mild or cold climates 4-5 years. Lately, the Japanese batteries seem to last longer. The battery in my previous car (the anti-Prius, a 2001 Pathfinder) was still going strong after 7 years! Now that's impressive, for use in Alberta! I was able to add distilled water to it, and that helped a lot.

    It's not hard to test the battery. Unfortunately, you can't add fluid, and water loss is the major cause of early failure. Even though it's "sealed", it does slowly loose water. That's why there is a vent tube. On the other hand, the Prius runs the battery at 13.7V and never draws large currents from it (35 Amp pulses max.), so it sees optimum conditions for battery life. Fully discharging it (leaving a light on, for example), will shorten its' life. The Prius battery tends to sit in "float" conditions, most of its' life.

    I've heard reports of $150 to $350 for a replacement. I think it depends on how big a boat the owner of the Toyota dealership has. ;) It should cost around $80 to $100, based on motorcycle battery costs. Call around for quotes (parts departments of Toyota dealers).
     
  5. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,075
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    <div class='quotetop'>QUOTE(KD6HDX @ Jul 30 2007, 02:41 PM) [snapback]487537[/snapback]</div>
    I'd use at least AA cells for your roadside assistance package. D cells would be even better for jump starting a Prius. :rolleyes:

    Tom
     
  6. KD6HDX

    KD6HDX New Member

    Joined:
    Oct 30, 2005
    256
    4
    0
    Location:
    Chino Hills,CA
    Vehicle:
    2005 Prius
    Yeah buddy, I wish it was that easy. :lol: