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

Battery replacement

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Dominic&Leslie, Mar 5, 2020.

  1. Dominic&Leslie

    Dominic&Leslie Junior Member

    Joined:
    May 31, 2014
    19
    4
    0
    Vehicle:
    2012 Prius
    Model:
    Four
    Greetings, We own a 2012 Prius, and I believe our 12v car battery is on its way out.
    I have done some research on line for replacement batteries, and cost is a serious issue for us because we are retired and live on a fixed income (SS) which honestly stinks. lol

    I read an article and at the end (in the comments section), a gentleman made mention that he used a VMAX MB857-35 12V AGM group U1maint free battery, rather than any of the alternatives, and this saved him 50% off the average price of 200 bucks.

    My concern is, how would I you modify the battery posts to make the battery cables fit?
     
  2. Pluggo

    Pluggo Senior Member

    Joined:
    May 23, 2016
    608
    532
    0
    Location:
    Folsom, Pennsylvania
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Proper cable connections or adapters might be a better question for the manufacturer. Does it have a hose connection to vent the hydrogen? That would be my concern.
    [​IMG] [​IMG]
     
    jerrymildred likes this.
  3. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    The AGM battery on your Prius is designed to vent the gasses from charging outside the passenger compartment. Many batteries assume they will be used outside the passenger compartment. The Gen 4 now has the battery under the hood and is not similarly vented. Hydrogen gas in the passenger compartment can be dangerous!
     
    #3 Prodigyplace, Mar 6, 2020
    Last edited: Mar 6, 2020
    Tande, Raytheeagle and jerrymildred like this.
  4. burebista

    burebista Active Member

    Joined:
    Sep 3, 2019
    181
    124
    0
    Location:
    Romania
    Vehicle:
    2010 Prius
    Model:
    N/A
    Here in Europe I bought this for 50 bucks. I've had to modify a little the vent pipe to fit but was easy.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    You can pick up any old battery fyfifty bucks, get correct clamps at an auto parts store and modify the hold down bracket
     
  6. TMR-JWAP

    TMR-JWAP Senior Member

    Joined:
    Aug 12, 2016
    6,404
    6,062
    0
    Location:
    Columbia, SC
    Vehicle:
    2007 Prius
    Model:
    Touring
    Prodigyplace likes this.
  7. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,686
    39,234
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    @Dominic&Leslie maybe disclose your approximate location, give responders a better picture.

    My 2 cents: you're chasing crumbs; I would shop around, get the best deal you can on a 100% compatible battery, and move on. If your fixed income situation is so hand-to-mouth that an extra $100 is not possible, maybe time to get out of the car game.

    Our situation is not that different, and believe me, I sometimes wonder why we've still got ours.
     
    pjksr02 likes this.
  8. DooDahMon

    DooDahMon Junior Member

    Joined:
    Sep 8, 2019
    2
    2
    0
    Location:
    USA
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    I just ordered today a NAPA Legend Premium (Penn makes it so it’s made is USA) for $156 plus tax & $18 core charge. Reg price is $174. They have a deal now spend $150+ and save 20%. Also I think you get a free NAPA Racing baseball hat at the store. Another thing I liked was can order online and pickup/ pay at store.
     
    Mendel Leisk likes this.
  9. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,174
    4,078
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    You can just drive with windows down and with solar roof, turn on the fan feature to air out the battery gas.
     
    #9 Grit, Mar 6, 2020
    Last edited: Mar 6, 2020
  10. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    There is no fan feature related to the 12 volt battery mounted back in the hatch.
     
  11. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,608
    3,788
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    The reference is to the solar ventilation feature that passes air thru the cabin while the car is off (and sitting in the sun of course).
     
    pjksr02 and Grit like this.
  12. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    You mean the optional feature that was on very few cars? I immediately thought of the traction battery fan that all Prii have.
     
  13. Dominic&Leslie

    Dominic&Leslie Junior Member

    Joined:
    May 31, 2014
    19
    4
    0
    Vehicle:
    2012 Prius
    Model:
    Four
    Thank you everyone for all your helpful replies. We did finally break down and purchase an AC Delco AGM replacement battery from Amazon for 175.00
     
    Merkey and Mendel Leisk like this.
  14. Ed Beaty

    Ed Beaty Active Member

    Joined:
    Jul 13, 2018
    334
    309
    0
    Location:
    Salt Lake City
    Vehicle:
    2010 Prius
    Model:
    IV
    Good on you. Even though it's a bit of a hardship now, it's a critical piece of the Prius ecosystem and it'll save on hassles down the road.
     
    Merkey likes this.
  15. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,686
    39,234
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    DIY install is easy. Just needs a 10 mm box wrench. Disconnect negative first, reconnect last. Clean the posts and insides of clamps with some fine steel wool or what have you. Seal it up and dispose with garbage; it has lead dust. Wear safety glasses.

    Look for the vent port on the old battery before disconnecting, and if the new battery's compatible, it should have the same vent, same location.

    You lose radio presets, trip meter, may need to reteach window auto up*. And the car behaves a little odd:

    1. the next start up, it may be cranky, requiring you to shut down and start again.
    2. after start up, during the warm up, it may do an odd rev-up, recalibrating something.

    * If auto-up for the windows isn't working, run them down, then run them back up, holding the lever up constantly till the windows right to the top, then continue to hold for at least 2 seconds longer. That should relearn it.

    A memory saver cable on a jump pack, or extra battery attached, can avoid memory loss. But it's no big deal, might even be some benefits.
     
    Merkey likes this.
  16. PHDRPH

    PHDRPH Junior Member

    Joined:
    Jan 7, 2017
    25
    17
    0
    Location:
    USA
    Vehicle:
    2016 Prius
    Model:
    Four
    Enjoyed your comments. Especially about benefits of not using battery saver. What benefits?


    iPhone ?
     
  17. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,686
    39,234
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Saves all the aforementioned items. Oh and the clock.

    I've purposely disconnected a couple of times in the last month (doing a wiring mod), it's no big deal. But if you have the means, a memory saver is nice.

    I use a jump pack with a cig lighter style socket, and a cable with cig lighter plug one end, and OBD (with just the power pins at other end. It has indicator light to confirm connection.