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Fitting mobility 12volt AGM battery.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Britprius, Mar 3, 2013.

  1. R-P

    R-P Active Member

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    Do you have the link? Starterbatteries can supply more peak current so I am assuming they have lower internal resistance than mobility batteries.
    I have a link open in my browser (still have to view it, may be in Dutch) about Lithium batteries frying regular alternators due to (assumption, as said haven't seen vid yet) very LOW internal resistance. But mobility batteries would have a HIGHER internal resistance.
    So it all depends on charging algorithm: regular alternators have maximum voltage and when current drops, they may lower the voltage. On my Prius I don't remember having ever seen aything else than 14.1V charging voltage. So assuming (big assumption) it is basically a constant voltage source, charging a mobility battery would take a little longer. I don't see any problem with that, so therefor I am curious about the video you saw to see what wrong assumptions I am gping with.
     
  2. caminoramon

    caminoramon New Member

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    I need a 12 v battery for a 2004 prius, could I just buy a battery from walmart? is the toyota 12 v battery special?
     
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  3. C Wagner

    C Wagner Member

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    Yes, the battery is quite special. The consensus is that the OEM battery is worth it, in the mid to high $2xx price range. it should be an AGM type Battery with the correct JIS posts , positive on the left, in the correct size - or close.

    i did succeed in getting a $75 AGM U1 post wheelchair battery in, but I had to buy two adapters - U1 to SAE and I had to pop out the car-side JIS clamps and replace with SAE clamps. That was another $20 in parts. One result of my testing, the wheelchair battery was 35AH non vented and it seemed to work fine for a year in cold New England vs the 45AH vented OEM battery.
     
    #563 C Wagner, Apr 2, 2022
    Last edited: Apr 2, 2022
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  4. Kingsway

    Kingsway Active Member

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    I know this is an old thread - but still of use! Inspired by this I fitted a 55am Lucas Mobility battery 4 years ago, and it still tests like new. I would have bought the Ritar if it had been available at the time... But I have just found one currently on sale here in the UK for only £75.00!! (us91.00) Half the price of a 'genuione' Toyota bat.
    I'm tempted to get one just to know I should never need to replace it in the life of the car (and possibly me!)RA12-55
     
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  5. PriusCamper

    PriusCamper Senior Member

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    I fully agree... Thanks to Brit Prius I installed a 55amphour 12v and it lasted me 9 years! Currently in the US I recommend this 12v as the best price and quality: https://ebay.us/5n8222
     
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  6. Tombukt2

    Tombukt2 Senior Member

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    I bought a UB series battery the universal thing I had one of my motorcycle I think it paid like 50 something dollars and it'll be back there until a long time goes by I imagine they don't really do anything do they
     
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  7. C Wagner

    C Wagner Member

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    Let us know how this goes. I think those are only 12AH, which is only about 1/4 of the original 45AH OEM battery. It would be neat if it works OK, after a year or two. If your car has SKS (keyless ignition, doors open as you walk up) you may want to turn the SKS system off to save the battery when you're not using the car for multiple weeks, like on vacations - as Toyota spec'ed 35AH without SKS and 45 with... Heck, all of us with SKS may want to turn it off when the car won't be used for long periods. Switch on Gen 2 is under the steering wheel...
     
  8. csutton7

    csutton7 Junior Member

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    Just an update. I've been running the same Harbor Freight battery for over 5 years now. Never had a problem with it. I use my Prius as a work truck and often have the hatch open for 8 hours or longer (with interior lights on). I always have a jump pack, but I've never had to use it on me. Quite a few times on other people's cars.


    IMG_4380.JPG
     
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  9. PriusCamper

    PriusCamper Senior Member

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    Wow, that trailer is awesome! Did you build it yourself? Love the look... I need to build something like that for all my tree pruning and gardening gear that lives inside my Prius.

    PS: Are those lights on your rear bumper cover? Do you use them very often?
     
  10. Tombukt2

    Tombukt2 Senior Member

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    What part of South Carolina I got family down in Gaffney and down in Greenville yeah that's a cool setup I have a similar thing for my prii.
     
  11. csutton7

    csutton7 Junior Member

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    Yes. To be honest, it started as me backing into my trailer and messing up my bumper cover, couldn't see good enough. It was where the right light is. Instead of fixing it, I ordered a couple lights, cut the hole bigger, mounted the light in the hole, and put a switch on my dash so I could have proper "backup lights". Now the people down the street know when I'm backing up. :) I bought the trailer with the toolboxes attached. Added the ladder rack. It's actually a seadoo trailer underneath it all. Very sturdy.
    I've done a little tree work myself... Battery powered chainsaw of course. :)
    This was before adding the lights, and the ladder rack.

    IMG_2894.JPG


    FYI. Also works for light concrete work.

    IMG_1952.JPG
     
  12. csutton7

    csutton7 Junior Member

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    I'm in Spartanburg. Just moved here from Laurens. I work a lot on the coast of NC. 7 hour drive. The Prius rig has paid for itself multiple times over in mileage. Only have to feed it tires :) but i can't complain. I'm severely overloading it. And asking a lot for it to pull a trailer too.
     
  13. Jama707

    Jama707 Junior Member

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  14. Tombukt2

    Tombukt2 Senior Member

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    Usually with these I just use some medium density foam buy some pieces I don't know what are they about 3 in thick maybe four so you can put your battery strap business back on or technically back there in the back like that where it's sitting you can put some foam just in the tray around the sides of the battery and leave the strap off unless the car gets upside down you're still in pretty good shape but I don't think they're any direct adapters for that size to make the height to make the battery strap work with one piece I have a UB in one prius
     
  15. Jama707

    Jama707 Junior Member

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    Thanks!

    I think I found https://www.ebay.com/itm/192195737259
    I was not sure what to search - it's SAE To JIS Car Battery Terminal Connector
     
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  16. Tombukt2

    Tombukt2 Senior Member

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    That doesn't seem correct that seems like it would be going from the Toyota original battery type top terminal to j i s which I guess is the round bar at the back of the holes that go on the regular battery You're trying to go from like a lawn mower looking battery top square holes in the post isn't that right? So in reality you're really lucky because you can just undo your positive terminal and put a piece on there that will allow you to just go through the square hole with the little 6 mm screw washer and nut and the ground is of no consequent I mean that's an easy one to do You can just cut that and put a crimp a round eye onto that and boom the washer through the eye 6 mm bolt lock nut and that's that
     
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  17. csutton7

    csutton7 Junior Member

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  18. YoJason

    YoJason New Member

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    Wow its been a long read but you guys helped me make a decision. I just bought an 06 and the battery started losing power when doors were open to long. Its non SKS so I bought the smaller battery from Home Depot. A mighty Max AGM for like $75. Had the screw in post. I bought some bold anchors and were about the right size and used the insert and a longer bolt. Grinded the neg just a bit. Worked well. Just added 1.25 " piece of wood underneath and everything bolted in just fine. So far so good with the battery but its only been a few days.

    Thanks all.
     
  19. R-P

    R-P Active Member

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    I bought the 55Ah in Januari 2016. It's been excellent so far but I feel it's getting old. I planned for it to outlive the Prius, but I never accounted for how long I am appearantly keeping it ;)
    No issues yet, just a little low voltage when measuring it recently (iirc 12.0V with nothing running but the dome and bootlight) and the dome light is kinda dim and really gets a lot brighter when the 200V battery takes over.
     
  20. Tombukt2

    Tombukt2 Senior Member

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    The dome light business is usually the door switches or something else in the system that's causing the dim business put lower draw non-incondescent bulbs in place and you won't even see this as long as you have 12 volts you're good not 11/9 ...12 And then when the car is on ready you have 13.7 to 14.5. And you should be good generally if you measure in the morning after an all night sit and you have 12 volts you're in good shape.