12V Battery's Life Expectancy

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by rcshaw777, Aug 21, 2011.

  1. rcshaw777

    rcshaw777 Junior Member

    Joined:
    Jul 21, 2011
    17
    2
    0
    Location:
    Malaysia
    Vehicle:
    2011 Prius
    Model:
    N/A
    Hi all,

    Wondering whether anyone can share your experiences or knowledge of the 12V battery life expectancy?

    I read the manual that if the 12V battery fails, need to jump start to enable the car to power up and shift the gear to N.

    Well I don't want to find my vehicle 12V battery drain. How long can the 12V battery last? What is the recommended period to replace the battery?
     
    Alfred Focke likes this.
  2. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    704
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
    At least for the Gen II, typical 12V battery service life is ~4 years.
    Lengthy service in extremely hot or cold climates results in some
    unquantifiable reduction.

    That said, a few owners have reported the battery lasting up to 6 years.

    Leaving a door or the rear hatch ajar, or the interior lights on overnight
    will usually result in the 12V battery being run down and the car will not
    start. The 12V battery is needed to boot-up the various computers and
    ECUs, and to bring the HV battery on line.

    Having to jump start a Prius is a potentially costly event.
    If the cables/polarity of the jumpstart battery are reversed, even for
    just a moment, there is a strong possibility that you can damage one
    of the computers, at some $2K replacement cost.

    Be very careful, and don't allow anyone else to jump start your car.
    As a safeguard, you can buy jumper cables that have built-in circuitry
    to prevent reverse polarity.
     
    lisa rowe likes this.
  3. Mendel Leisk

    Mendel Leisk Titanic Social Director

    Joined:
    Oct 17, 2010
    36,341
    25,139
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    My personal preference is to replace it after 4 years, regardless of condition. As times goes by it becomes increasingly likely that it will fail, even if you've never had a mishap such as leaving lights on. Four years just seems a good balance between risk and expense, for me.

    Our usuage is regular. On the other hand, people with emergency vehicles, ambulance police, etc., will replace batteries bi-yearly, or even yearly.
     
    WilDavis likes this.
  4. xs650

    xs650 Senior Member

    Joined:
    Jul 2, 2010
    4,539
    1,417
    9
    Location:
    Northern California
    Vehicle:
    2010 Prius
    Model:
    II
    My magic number is normally 5 years, I recently forgot and ran 5 years 2 months on my other car and the battery died. I may only do 4 on the Prius because of the battery problems people have been having.
     
  5. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,053
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    The advice above will help keep you out of trouble but I would recommend checking the voltage at the battery with a volt meter twice or more a year. This will help you keep tracks of your battery condition.
     
    Prius Maximus likes this.
  6. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    18,058
    3,032
    7
    Location:
    Northern Michigan
    Vehicle:
    2006 Prius
    Still on the original 12V for my 2006. We don't drive much, so ours sits for days and weeks at a time. Our climate is pretty easy on batteries. Likewise this one has only suffered one "lights left on" episode, so it hasn't been abused.

    Given its age, I keep a jump box in the back, but have only used it the one time my wife left the map light on.

    Tom
     
  7. Charles Suitt

    Charles Suitt Senior Member

    Joined:
    Oct 8, 2004
    1,637
    13
    0
    Location:
    Dallas TX
    Vehicle:
    2012 Prius
    Model:
    Four
    My 2007 Touring 12v battery lasted 4.5 years, died while I was shopping for our new 2012 IV. I had left the '07 running while looking at a '12 after removing a CD to test the player on the '12. I expect our new 2012 IV 12v battery to last a minimum of 3 to 4 years.
     
  8. mainerinexile

    mainerinexile No longer in exile!

    Joined:
    Mar 14, 2010
    403
    72
    0
    Location:
    Maine
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    In addition to the previous comments, a number of people have reported that gas mileage drops precipititously when the 12v battery begins to fail, even when not noticeable by performance. My 2010 with 53,000 miles has suddenly gone from low 50 mpg to low 40 mpg. Has anyone heard of a 12v battery failing this early?
     
  9. penquin230

    penquin230 "Golden Hawk"

    Joined:
    Oct 21, 2008
    85
    12
    0
    Location:
    Atlanta, Ga.
    Vehicle:
    2010 Prius
    Model:
    IV
    MY Prius was built in January of 2005...I replaced my 12v battery November 2011 ...That's 6 years and 11 months...:)...never had a problem with battery. I checked voltage last November and voltage was :eek: 9.95vdc. I decided it was time. I replaced it with an Optima battery. I figure I'm good for 7-10 years now. :cheer2::rockon::cheer2:
     
  10. Jon Hagen

    Jon Hagen Active Member

    Joined:
    Mar 6, 2011
    336
    133
    0
    Location:
    North Dakota
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Because of work load and weather, I have not driven my 2010 Prius for nearly 3 weeks,
    I was in the garage a few days ago and thought I should charge the 12V battery. I opened the under hood fuse box and hooked my BatteryMINDer trickle charger/ maintainer/ desulfator to the jump start terminal and let it do it,s thing.

    I was not too happy to see that at the 1.3 amp charge rate, it took 18 hours for the charger to switch from charge to desulfate / maintain mode, so I suspect the 12V battery was atleast 50% discharged.
    The BatteryMINDer charger/ maintainer/ desulfator units are one of the best avalible, one of the few maintainers that are rated for use on a sealed AGM battery like what is used in the Prius.

    The little BatteryMINDer units come with two plug in 12V wiring harness, one with ring terminals for permenent installation on the battery posts, the other with battery clips.
    It's a bit clumsy to open the fuse box and connect at the jump start terminal, so I will install the permanent harness on the battery , with the plug and batteryMINDer in the below floor storage tub, where it is easy to acess to plug in for those times when the Prius sets too long.

    If not allowed to do much deep cycling,I suspect the original battery should last 10 years.


    EDIT: I just finished installing the BatteryMINDer permanent wiring harness in the battery compartment and storage tub. took all of 10 minutes, Why did I not do this 3 years ago when the car and 12V battery were new. :-(

    Here is a link to the BatteryMINDer charger / maintainer./ desulfator.
    http://www.northerntool.com/shop/tools/product_200332201_200332201
     
  11. almypal26

    almypal26 Member

    Joined:
    Jun 29, 2010
    101
    1
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III

    I have 56,000 miles on my 2010, still getting lo to mid 50's on the mpgs.:D
     
  12. jabecker

    jabecker driver of Prii since 2005

    Joined:
    Jul 7, 2005
    448
    77
    1
    Location:
    Portland, Oregon
    Vehicle:
    2012 Prius
    Model:
    Four
    The battery in my 2005 lasted 7 years and 65000 miles. Fortunately it died in my driveway.

    I did notice that my mileage wasn't as good for the last year or so. I averaged around 47 - 48 rather than the 52 -53 that I had been getting.

    I think I'll replace the one in my 2012 at around 5 years or so.
     
  13. Feri

    Feri Active Member

    Joined:
    Jun 25, 2011
    761
    141
    0
    Location:
    Maldon Victoria Australia
    Vehicle:
    2010 Prius
    Model:
    III
    My 2010 was built in August 2009. I have just replaced the battery but I stupidly allowed it to go completely flat a couple of times. :mad:
     
  14. almypal26

    almypal26 Member

    Joined:
    Jun 29, 2010
    101
    1
    0
    Location:
    So Cal
    Vehicle:
    2010 Prius
    Model:
    III
    Is the 12v battery life based on time, mileage or both? I have 56,000 miles on my 2010 (purchased in Oct. 2009).:eek:
     
  15. adamace1

    adamace1 Senior Member

    Joined:
    Jun 22, 2009
    1,403
    185
    0
    Location:
    Charlotte, NC
    Vehicle:
    2010 Prius
    Model:
    II
    Temps play a part in it too.
     
  16. Eoin

    Eoin Active Member

    Joined:
    Oct 6, 2009
    593
    116
    0
    Location:
    Long Island
    Vehicle:
    2010 Prius
    Model:
    IV
     
  17. Eoin

    Eoin Active Member

    Joined:
    Oct 6, 2009
    593
    116
    0
    Location:
    Long Island
    Vehicle:
    2010 Prius
    Model:
    IV
    Just replaced my 12 volt battery on my 2005 Prius with 136k miles. I guess 8 years is not bad.
     
  18. prius cabbie

    prius cabbie Junior Member

    Joined:
    Apr 28, 2013
    14
    1
    0
    Vehicle:
    2013 Prius
    Model:
    Two
    Mine lasted over 7 years in a NYC Yellow Taxi. 160000 miles. Incredible. 2005 prius
     
  19. zander

    zander Junior Member

    Joined:
    Jun 24, 2010
    46
    3
    0
    Location:
    connecticut
    Vehicle:
    2010 Prius
    Model:
    II
    Check the fluid level in your battery 2 times a year. If you need to add denatured water, ok and This will extend the life of the battery
     
  20. kknguyen1168

    kknguyen1168 Member

    Joined:
    Jan 15, 2011
    451
    34
    0
    Location:
    san diego
    Vehicle:
    2010 Prius
    Model:
    III
    Zander

    you can not add the water to Toyota 12v battery.
     
Loading...