My 12V battery is 6 years old & working fine=Should I replace it before 3000 mile trip?

Discussion in 'Gen 2 Prius Main Forum' started by ski.dive, Apr 11, 2019.

  1. kenoarto

    kenoarto Senior Member

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    Preemptive replacement also allows for plenty of price shopping. You won't get any bargains for an emergency tow and replacement in a shop, in the middle of nowhere, at midnight.

    Posted via the PriusChat mobile app.
     
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  2. fuzzy1

    fuzzy1 Senior Member

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    Which isn't when any of my batteries have ever died. Actually, none have died 'without prior warning' since my college days, when I didn't know what warning signs to watch out for.

    When my Subaru battery was badly stressed at -15F this January (symptom was electric power steering failure, apparently a known cold Subaru issue), the non-shopping price was $70 above a good price. But they were fresh out from a big run of customers before me, so I just continued on with a stashed battery tender, extension cord, and indoor parking the next night. Total extra cost: 30 minute detour to a shop after the ski hill closed (no morning delay, no lost ski time, which is why I missed the available battery supply), plus $15 for indoor parking. With temperatures subsequently warming to -5F and above, and some battery tending just to be sure, it finished the rest of the trip just fine.

    One can turn these into expensive, scary emergencies. Or not.
     
    #42 fuzzy1, Apr 14, 2019
    Last edited: Apr 15, 2019 at 12:02 AM
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  3. kenoarto

    kenoarto Senior Member

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    Leave a door ajar overnight... on a cross country road trip... in the mountains...or Nebraska...or Texas...

    Posted via the PriusChat mobile app.
     
  4. fuzzy1

    fuzzy1 Senior Member

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    Replacing batteries early won't prevent the door from being left ajar.

    That is why I changed all those interior lamps to low current LEDs models. Now the door can be left open all night, and possibly considerably longer (depending on LED choice and battery condition) without draining the battery to failure.
     
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  5. kenoarto

    kenoarto Senior Member

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    In this case, we know the battery is 6 years old and at the end of it's excpected life. Some day SOON, the car won't start and/or throw numerous warning lights and trouble codes. By your trolling logic, do you also run the car out of gas/fliuds or are those trivial inconveniences, too ?!?

    Posted via the PriusChat mobile app.
     
  6. Mendel Leisk

    Mendel Leisk Sidewalk Supervisor

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    In the underfloor tray I carry a full size jump pack, an older model CTEK smart charger and an extension cord. Insurance for the door-ajar-overnight.
     
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  7. Skibob

    Skibob Senior Member

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    I try to carry nothing in my car. Toyota went to great lengths to keep the cars weight down, you don’t need to add unnecessary weight. Plus you barely drive anywhere why don’t you just get a tow package?
     
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  8. Georgina Rudkus

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    Even Lindbergh carried emergency gear, when he was a stickler for eliminating extra weight on the Spirit of St. Louis.

    Many Northern Californian's have died having been stranded in snowstorms, not having carried basic survival gear.
     
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  9. fuzzy1

    fuzzy1 Senior Member

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    ... especially when traveling north of Northern California. This one is merely the best known case:
    James Kim - Wikipedia
     
  10. Skibob

    Skibob Senior Member

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    So your comparing someone crossing the Atlantic to someone who most likely never drives more than 100 miles from home?

    As someone who lives in Northern California I can tell you that while you are correct that some people die from getting stuck in a snowstorm you missed the fact that they mostly die because they went off the normal routes because the main routes were closed. That’s the number one reason they die.
     
  11. Raytheeagle

    Raytheeagle Senior Member

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    This Northern Californian made sure to have his emergency kit, air compressor and jump pack transfer over to the Prime along with a multimeter and other various needs, even though the Prime lacks storage space;).

    As an Eagle Scout, I believe in Be Prepared:).

    Spare tire coming soon(y).
     
  12. Skibob

    Skibob Senior Member

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    Nothing wrong with being prepared on a long trip, but day to day commute? Heck I do the same thing for a long trip, but day to day a good tow package gets my car Back home to be repaired. I’m not gonna fix my car on the side of I 5 or I 80. Just too dangerous.
     
    #52 Skibob, Apr 15, 2019 at 11:36 PM
    Last edited: Apr 15, 2019 at 11:43 PM
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  13. Georgina Rudkus

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    In the mountains or even the hills in western North and South Carolina, one does not have to go 100 miles or more to get stranded. We've had local people run off the road in a wash and be injured and hidden in the brush for days.
     
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  14. Skibob

    Skibob Senior Member

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    So there will be electricity for someone to hook up their battery chargers in these areas?
     
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  15. fuzzy1

    fuzzy1 Senior Member

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    Mendel's full size jump pack needs an electric outlet to plug in to while it is jumpstarting a car? I didn't know that. :)

    Though for ordinary offroad/offgrid emergencies, Ray's other emergency kit and flat repair tools will generally be more useful.
     
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  16. fuzzy1

    fuzzy1 Senior Member

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    Maybe you know that, but I don't. In my current climate zone, past batteries (before Prius) have gone 7 to 9 years before I wimp put and replace them. While that is longer than the national average -- other Prius owners here seem to start reporting dead batteries around 3 years, and most are gone by 6 -- there seems to be a few zones that do even better than my area.
    If trolling is in order, then by your logical parallel, do you also use only the top 1/2 to 1/3 of a tank of gas, then pull into a fuel station and drain out all the 'old stale' gas before refilling with an entirely fresh new tank of gas? And you demand that the rest of us do the same?

    Your gas tank troll is bogus because we (or most of us) don't discard still-usable gas at refill/replacement time. We keep it and use it. Battery replacement means discarding all the remaining usefullness of the item before it is actually depleted. For many of us in milder climates, your preferred schedule means throwing away a lot of useful life, at significant expense.

    I have been crystal clear that battery life involves a cost-benefit tradeoff, and different people have different goals and tolerance limits, thus leading to different balance points. I.e. I have no problem with fire trucks and ambulances replacing at just two years, very early on the age-failure curve, because to them the cost of a failure-related delay is potentially very high. Likewise, I see no reason why those of us who have are merely cheaply inconvenienced by battery failure, and have a good feel for how weak the battery is getting vs our personal tolerance limit, should be forced into replacements years early by the angst-ridden fearmongers whose first response is a panicked call to an expensive tow truck.

    Most people will fall at differing points in between.

    OP's battery has made it through the cold of winter into the warmth of spring. The risk of it failing in the next warming month is very significantly less than it was during the just-past several cold months. But it isn't zero, hasn't been zero for at least four years, and rises every year. He'll need to select his comfort level, based on his particular trouble cost of an actual failure. His climate zone (home and/or trip destination) is also a factor.

    A few tools mentioned in this thread (voltmeter, battery tender, OBDII port monitor, etc.) can help make a more informed judgement, for those who wish to put in the effort. This effort pays off more for folks with multi-vehicle fleets than of those with just a single rig.
     
    #56 fuzzy1, Apr 16, 2019 at 1:27 AM
    Last edited: Apr 16, 2019 at 1:23 PM
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  17. Mendel Leisk

    Mendel Leisk Sidewalk Supervisor

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    Jump pack to get you going, Extension cord and charger at the motel. This is basic stuff, lol.
     
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  18. egn83b

    egn83b Junior Member

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    The time to replace the aux battery is easy. Turn on the AC blower and watch the hybrid battery start dropping faster then normally that is your que to replace the battery. Typically you can run the blower for 10 to 20 minutes before you lose a bars of battery and the car turns on. However on a low aux battery the car will recharge its self but will keep running longer then normal after the hybrid battery is at 3 bars.

    Posted via the PriusChat mobile app.
     
  19. davisdaler

    davisdaler Junior Member

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    There is a simple method via the center panel touch screen to test the 12v battery. Google it , there are you tube videos to show how. There are 2 tests, voltage at rest ,(12.5) and voltage under load when accessory power button is activated. (12.0) if you are below these values , time to replace. Best battery for my 09 was a Bosch at pep boys. Best price as well.

    SM-G955U ?
     
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  20. mczouav

    mczouav Junior Member

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    Hello, just out of curiosity, did some of you guys ever try to connect supercapacitors in parallel to your prius s 12-13 v battery? A year ago I built a 6 supercap voltage regulated board (200 A ish capable, board form ebay) with thick copper wire soldered on the Scap board leads as enhancement. I had it installed in my wife s honda accord with a 7 y old battery. 1 year ish later, one morning, the honda did not start straight away. After cranking it (with insistance) several times wife freaked out and reached for me. I just cranked it after making sure with a car plug voltmeter that the weak battery had recharged the supercapacitors enough to give a good kick (20-30 sec) and it worked. Not stranded. Wife could go to work and came back fine in the evening ( i explained her the strategy.) We got a new battery that week end. My point is that the supercapacitor can help a lot not to get stranded... Even though it only gives a part of the cranking power needed, it was sufficient in our case.

    Posted via the PriusChat mobile app.
     
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