Replaced 12v Lead with 12v Lithium

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You're right that heat kills the big battery. (aka LiIon traction battery).
I've never seen data showing that cold kills the small battery (aka lead-acid 12V battery). Heat definitely kills lead-acid batteries. That is well documented.
On ICEs, cold temperature puts heavier demand on lead-acid batteries, so people with ICEs see their cars fail to start in cold weather, but that's for another forum.
Bob
 
Heat definitely kills 12-volt batteries, but it is not as much of a problem in a LEAF because under hood temperature is much lower than an internal combustion vehicle. Causes of early failure of 12-volt batteries in my climate:
1. High under hood temperrature.
2. High charging voltage.

The LEAF has much lower under hood temperatures than ICE vehicles and charging voltage is slightly lower than some other cars. These two issues translate to longer battery life in a LEAF under my useage/charging conditions.
 
GerryAZ said:
Heat definitely kills 12-volt batteries, but it is not as much of a problem in a LEAF because under hood temperature is much lower than an internal combustion vehicle. Causes of early failure of 12-volt batteries in my climate:
1. High under hood temperrature.
2. High charging voltage.

The LEAF has much lower under hood temperatures than ICE vehicles and charging voltage is slightly lower than some other cars. These two issues translate to longer battery life in a LEAF under my useage/charging conditions.

+1
 
No, I'm not confused. Heat speeds up the chemical reaction in all batteries. Everytime i have had a 12 volt battery go bad here in south Florida, the mechanics say the same thing: "the Florida heat cooks batteries. You can't get more than 3 years out of them" .
I've actually had better luck than that, usually 4+ years. The Leaf battery was especially impressive considering how it got bricked a few times by their bad charging scheme, and it still came back to life again. My Galant VR-4's were the worst, because of the underhood heat.
 
My original 12v battery lasted about 5 years without issue until the very end of life. I began getting ev warning issue and after reading forums I just went ahead and changed the battery with and interstate battery last year. Fast forward 9 months and I walk out to get in the car and it's dead. I pulled the batter threw it on a charger it was almost dead. I took It back and they replaced it due to dead cells. Fast forward two more months with new battery and it's also dead. Threw it on charger, no problems. I had a Nissan recall so while I had it at the dealer I had them test the charger to make sure everything was okay. All tests were fine. After another dead battery I decided to throw it in my v8 Toyota tundra for a stress test. Everything has been fine for 3 months and tonight I'm in the rain charging my battery again! The voltage shows 2.8v. I assume this battery is toast too. Sorry for a long drawn out question but information is always useful. Are there better lead 12v than others for ev? Why did my first battery go so long with no issues? Thanks for any info.
 
I have a 2013 about every 6 weeks or so for some reason I find a dead battery. I firmly believe that once in a while the car keeps something on the 12v side on and running and no matter what battery you have it runs the 12v battery dead. I gave up on trying to diagnose it a while ago and now I throw a deltran 1.25 amp charger on it twice a week, although I still get a random dead 12v after sitting once in a while.

One of the things I have done that helped a lot, going from once a week dead to about 6 weeks or so was to unplug the current sensor on the negative lead of the 12v battery. This makes the car charge to about 14v all the time while it is on. The advantage of this is the 12v battery is getting more charge. It had been charging to about 14v then after a minute or so dropped to 12.6, which is fine to run things but (in my opinion) does not fully charge the battery if drained somehow.

I also threw in a larger 34N battery in as well.

https://www.mynissanleaf.com/viewtopic.php?f=9&t=18129&p=439206#p439206
 
BrockWI said:
I also threw in a larger 34N battery in as well.

https://www.mynissanleaf.com/viewtopic.php?f=9&t=18129&p=439206#p439206

Your other suggestions are all good, but I don't want folks to think that a higher capacity 12v battery is necessarily the solution. In fact, the Leaf can operate with a much lower capacity 12v battery (my Lithium replacement is ~20AHr) than originally supplied.
 
tomy2t0ne said:
.... Are there better lead 12v than others for ev? Why did my first battery go so long with no issues? Thanks for any info.

Lead-acid batteries can fail for a number of reasons. There can be bad internal connections between cells. There can be internal shorts that drain the cells. These can be intermittent. There can also be external shorts. Examine the top of the battery case in particular. If it is moist or has a layer of moist dust accumulated, acid or acid mist from the battery could have formed a conductive path along the top of the case between the terminals or between the positive and a grounded metal tie-down. Keep the top of lead-acid car batteries clean. Some batteries are defective from the factory, damaged in shipment or improper storage and handling.

EV doesn't particularly need special battery. Deep-cycle capable AGM batteries do offer some advantages for cars in general and are good to have for an EV especially one you intend to keep long-term.
- better tolerance of deep discharge
- no leakage
- no corrosion
- faster charge acceptance
 
tomy2t0ne said:
My original 12v battery lasted about 5 years without issue until the very end of life. I began getting ev warning issue and after reading forums I just went ahead and changed the battery with and interstate battery last year. Fast forward 9 months and I walk out to get in the car and it's dead. I pulled the batter threw it on a charger it was almost dead. I took It back and they replaced it due to dead cells. Fast forward two more months with new battery and it's also dead. Threw it on charger, no problems. I had a Nissan recall so while I had it at the dealer I had them test the charger to make sure everything was okay. All tests were fine. After another dead battery I decided to throw it in my v8 Toyota tundra for a stress test. Everything has been fine for 3 months and tonight I'm in the rain charging my battery again! The voltage shows 2.8v. I assume this battery is toast too. Sorry for a long drawn out question but information is always useful. Are there better lead 12v than others for ev? Why did my first battery go so long with no issues? Thanks for any info.

Verify that your TCU (cell modem in the car) is either disabled (if 2G) or has the latest firmware (if 3G). There's a known issue where the TCU gets stuck and drains the 12V battery. If you don't use carwings or the Leaf App, I recommend you disconnect the TCU entirely so it can't cause any battery drain. I've documented how to do that here: https://www.mynissanleaf.com/viewtopic.php?t=25949

Once you've done that, I would recommend an AGM 12V battery. These tolerate deep discharge and partial storage charge much better than the standard 12V batteries. An AGM battery is more expensive than a standard battery, but not charging the battery in the rain is worth it.

I suspect if you do both of these things, you'll be fine and not have problems in the future. You should not be having these problems--while Leafs are renowned for killing the 12V battery early, your experiences are atypical. Most Leaf owners are getting years out of their batteries, not months.
 
tomy2t0ne said:
My original 12v battery lasted about 5 years without issue until the very end of life. I began getting ev warning issue and after reading forums I just went ahead and changed the battery with and interstate battery last year. Fast forward 9 months and I walk out to get in the car and it's dead. I pulled the batter threw it on a charger it was almost dead. I took It back and they replaced it due to dead cells. Fast forward two more months with new battery and it's also dead. Threw it on charger, no problems. I had a Nissan recall so while I had it at the dealer I had them test the charger to make sure everything was okay. All tests were fine. After another dead battery I decided to throw it in my v8 Toyota tundra for a stress test. Everything has been fine for 3 months and tonight I'm in the rain charging my battery again! The voltage shows 2.8v. I assume this battery is toast too. Sorry for a long drawn out question but information is always useful. Are there better lead 12v than others for ev? Why did my first battery go so long with no issues? Thanks for any info.

Did you change your charging behavior at all? The number one suspect in cases like this is leaving the car plugged in but not charging, either because charging has ended or because it won't start for hours because a charge timer is being used. Doing either of these once or twice won't kill the 12 volt battery, but doing it regularly might.
 
Hi, so it's late winter here in the UK and my wife's Leaf was dead when she returned to it an hour after driving for 20 mins to a soft play.

Having now got it going again through a simple jump start, my quesiton is just what do i need to monitor and how in order to assess the need for a battery replacement.

It is her regular drive, she charges about 2-3 times a week overnight on 32A home circuit.

It's a 2014 and I presume battery is original. We obtained it in 2018 with 2000 miles on the clock (seems to have been some sort of corporate pool car that was hardly used when in their ownership)

I have a battery charger (smart, but not maintainer/trickle charger) and I know how to use a multimeter. I have also used LeafSpy at one point, but haven't looked at that in some time.

I could just replace the battery, but EV driving was supposed to be about cheap lifetime ownership. With the high upfront cost, if i have to start replacing 12v batteries it's not going to be cheap for long.

Basically, how can one tell whether the health of a 12v is declining without my wife getting caught again?

(I was away from home on this occasion and after 3 hours the rescue people hadn't shown up, luckily a friend's husband gave her a jump start. The frustrating aspect of this story is when she called me I told her to get a jump from someone on the car park. She duly did, apparently with no success. hours later she asked 'is the donor car supposed to have it's motor running when jumping?' Oh well. She'll know next time!)
 
boilingfrog said:
It's a 2014 and I presume battery is original. We obtained it in 2018 with 2000 miles on the clock (seems to have been some sort of corporate pool car that was hardly used when in their ownership)
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[edit]
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I could just replace the battery, but EV driving was supposed to be about cheap lifetime ownership. With the high upfront cost, if i have to start replacing 12v batteries it's not going to be cheap for long.

I didn't need to read any further than the first sentence (above) to know you need to replace your 12v battery; there's too many things that can go wrong with a Leaf on a marginal 12v battery.
If you think replacing 12v batteries is expensive, try replacing starters and alternators ;)
 
Agree with Leftie. You have a 6 year old Pb battery. If you live in a hot are the lifespan can be as little as 3.4 years. Once you start running it 'dead', to the point of needing a jump it's shot.
There is some evidence that the Leaf 12v charging system is not as robust as an ICE. Depending on your charging and use habits it may not be getting an optimal charge. I purchased a battery tender and top mine up 1-2x/month and am tracking it. It's a 2014 also, certainly not new, but so far hanging in there.

For a great lesson on batteries go here: https://batteryuniversity.com/learn/article/how_to_restore_and_prolong_lead_acid_batteries
 
joeriv said:
IMHO every EV owner should have a 12 volt battery tester
Maybe "EV owner" should be "LEAF owner". The problem of insufficiently charging the 12V battery seems particular to the LEAF.
 
I would try charging the 12v and see if it gets "full" in an hour or so. If it does that means it is all either fine now or it is bad and not holding much power any more. If it were me I would give it one more try and if it does again swap it out. But I also carry a 12v jump starter battery in the Leaf.
 
I too have a 12v lithium ion jump starter - my three essential Leaf accessories:

o 12 volt jump starter
o 12 volt battery tester
o 12 volt trickle charger
 
joeriv said:
I too have a 12v lithium ion jump starter - my three essential Leaf accessories:

o 12 volt jump starter
o 12 volt battery tester
o 12 volt trickle charger
+1 as do I. I also occasionally(every month or so) use the trickle charger for as long as I can, at least overnight and knock on wood am still on my original '13pb battery. And as I have the lithium jump starter I'm not too worried should the car not start because of a weak 12v battery, just jump start it myself and move on. After doing this a time or two I'd just replace the 12v battery. Note for my '12 Leaf I used a Optima yellow top battery(3x the cost of a regular cheap pb battery) but still half the cost of a replacement Li battery and I'll probably do the same when the pb in my '13 finally dies.
 
jlv said:
joeriv said:
IMHO every EV owner should have a 12 volt battery tester
Maybe "EV owner" should be "LEAF owner". The problem of insufficiently charging the 12V battery seems particular to the LEAF.

Tesla owners also had problems with premature 12V battery failures, and Tesla decided to switch to deep-cycle 12V AGM batteries as original equipment.
 
My 2013 Leaf's 12V battery is over 6.5 years old, so I decided to monitor it as I L2 charged my Leaf. The initial voltage before beginning
charging was 12.00V. As plugged in the EVSE, the 12V battery voltage went to 14.40V. It then slowing reduced to 13.00V, about a minute
later. It remained at 13.00V during the L2 charging process.

Some may argue that a trickle-charge at 13.00V is inadequate to properly maintain a 12V battery. I have 2008 Mini that still
has its original 12V battery, having been trickle-charged since new (over 12 years). The same trickle-charging process is
used for my 2012 Nissan Xterra, and it still has its original 12V battery after 8 years.
 
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