12V auxiliary battery replacement

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Tracey
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12V auxiliary battery replacement

Post by Tracey »

Hi All,

I have had my 2012 IMiEV since June 2019 & I'm not sure if its ever had its 12v battery replaced.
I have noticed that the car radio sometimes won't come on or randomly stops working.
Any suggestion on what to buy as a 12V auxiliary battery replacement.
I'm in Sydney.

Kind regards
Tracey
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brendon_m
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Re: 12V auxiliary battery replacement

Post by brendon_m »

My experience of the factory stereo is that it's a bit crap so your radio issues may have nothing to do with the battery.
I'd be surprised if someone got 8 years out of the battery, possible but I'd say it's probably been replaced before and is coming up due again. With some of the stories out there it certainly seems it's a case of better safe than sorry when it comes to the 12V battery in imievs so I'd replace it if you have any doubts.

We sell Exide batteries at my work and most people get a pretty good run out of them (though we only stock the upper 'red top' range so I can't honestly speak for the 'economy' and 'endurance' ranges) and I'm happy to recommend them but really as long as you replace it with is any reasonable quality name brand battery you should be fine. Just don't go to Supercheap and get the cheapest one they have, it's asking for trouble. In the world of batteries you do get what you pay for and if a battery doesn't come with at least a 2-3 year warranty then there's probably a reason for that.
praxidice
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Re: 12V auxiliary battery replacement

Post by praxidice »

I had to replace my 12v battery after three years but there weren't any problems with the standard radio other than the fact that everything running off the 12v battery stopped working. It isn't that the 12v battery has a hard life because it doesn't encounter normal start loads, consequently an endurance style battery probably isn't indicated.
DougGlover
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Re: 12V auxiliary battery replacement

Post by DougGlover »

Don't forget - if you do not use your iMiEV for a while (a week or so) the 12V battery can discharge - the iMiEV did not charge the 12V battery even if left plugged in to the mains....

If you are not using your vehicle regularly, consider plugging the 12V battery into a trickle charger (or similar). This is one of the main reasons for 12V battery reduced life....
praxidice
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Re: 12V auxiliary battery replacement

Post by praxidice »

Possibly Its hardly surprising the 12v battery is overlooked in a Minicab, I only found it three years after I bought the vehicle because its hidden under the back floor mat and even the spare tyre needs to be removed to get at it. I didn't bother trying to charge it but maybe the bloke I gave it to did ... will ask him next time I see him.
Tracey
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Re: 12V auxiliary battery replacement

Post by Tracey »

Thanks everyone,

Anyone know what model number to buy?
praxidice
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Re: 12V auxiliary battery replacement

Post by praxidice »

Can't recall but it was a pretty standard one. Battery World knew what to use.
whimpurinter
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Re: 12V auxiliary battery replacement

Post by whimpurinter »

Hi,
My 2011/2012 imiev (not sure) went dead in the last week. Lucky I realised the most likely fault was the 12V battery and it was reading 3.8V. (I might have written this in a recent post??).
I put on the new-style charger and it came up good.
The radio asked for the 'code' to make it work (such a silly idea for the era - so many radios not worth stealing).
Lucky the previous owner had written the code down somewhere (but not in the expected location). Just saying you will need the radio code if you don't maintain the electricity during the battery changeover.
I put the dead battery down to what DougGlover said above :)
I'm wondering these days if it's better to keep your car fully charged and recharge from near empty every now and then and to forget the supposed benefits of not stressing the drive batteries. That way the batteries will be balanced more often ?? and the 12V battery will maintain its charge as it is charged well while the car is plugged in.
There needs to be a 12V battery charge indicator somewhere prominent (Do Tesla's avoid this situation???). :)
mikedufty
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Re: 12V auxiliary battery replacement

Post by mikedufty »

I believe that after early problems Teslas now turn themselves on periodically and top the 12v battery up from the main pack.
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brendon_m
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Re: 12V auxiliary battery replacement

Post by brendon_m »

For reference the battery in my 2010 is an AC Delco branded battery with the model number SM42B20LEFB and the part number is 19314494.
Looking at it I'd say it crosses to a X40CPMF from Exide (or 40CP for the cheap version)
T1 Terry
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Re: 12V auxiliary battery replacement

Post by T1 Terry »

I now build all my auxiliary batteries, and even the start battery for my diesel Hino, out of used LFP cells. No longer have problems with dead start /aux batteries ... well except for my high mileage Prius, but that is because the accumulator for the ABS keeps starting up even if the vehicle is unattended. Probably something I can sort at some point, but I haven't due to laziness, I just disconnect the battery if it's going to sit for a week or more.
Often these aux batteries are AGM or Gel type so acid spills and fumes are avoided, but that makes them rather expensive. I believe the replacement aux battery for my Gen 2 Prius would have cost over $375, so don't expect the battery to be cheap ....

T1 Terry
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mark_hetho
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Re: 12V auxiliary battery replacement

Post by mark_hetho »

Terry, do you use any kind of balancing system?

(side note: I had the original starter battery in our Prius last 15 years! and then replaced it twice in 3 years....)
DougGlover
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Re: 12V auxiliary battery replacement

Post by DougGlover »

It is not an expensive battery for the iMiEV - I got one recently for a hundred bucks or so from a local battery company. It is a basic (around 40Ah I think) small Japanese car battery.
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brendon_m
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Re: 12V auxiliary battery replacement

Post by brendon_m »

It's the same battery as fitted to older Subarus. For reference the X40CPMF is $145 at my work and the 40CP is $130 (the low price difference is why we don't bother to stock the cheap ones)
T1 Terry
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Re: 12V auxiliary battery replacement

Post by T1 Terry »

mark_hetho wrote: Fri, 15 Jan 2021, 05:27 Terry, do you use any kind of balancing system?

(side note: I had the original starter battery in our Prius last 15 years! and then replaced it twice in 3 years....)
I do have a HA02 https://www.amazon.com.au/Battery-Balan ... 2617&psc=1 on one of the batteries to see if it made any difference to the cell balance compared to the other batteries without a balancer, and there isn't much in it. In my case it is probably more to do with the poor condition the cells are in than an out of balance due to cycling. The 4 cell battery I built from the s/h grey CALB cells I bought from Chris Jones in WA are still at the same differential as when I installed them mths ago, 10mV at between 3.45v and 3.5v in each cell, around 3mV below that fully charged voltage. I'm never concerned unless the differential exceeds 150mV at the top end of charge anyway, so as a 4 cell battery they are fairly stable as far as the differential wandering.
I also have a 4 cell 40Ah battery given to me by a friend that bought up a heap of cells from a scooter rental mob. Some of the cells registered less than 1v when he got them, he removed the cell top balance boards and trickle charged them till they reached 4v per cell, then cycled them a few times and most have been fine ever since. That was more than 5 yrs ago, it is still in my silver '06 Prius after serving yrs of duty as our 12v jump start battery and power supply for the workshop.
It still started a 4 cyl Mazda diesel before it became the Prius auxiliary battery, not bad for a deemed unservicable 40Ah battery ......

T1 Terry

T1 Terry
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