Dead 12V Battery Overnight??

[LeftieBiker]

Just to make it clear about the difference between a working accessory battery and charged one: these batteries don't have to work as hard to start the car as a battery in an ICE car. They only need to provide a little bit of power to activate the relays that "start" the vehicle. This means that 20 minutes' worth of charging will "revive" the car, even though it would not be enough to restore the battery so it could crank an ICE over at normal speed. The fact that the battery is working *enough* masks the fact that it is still nearer dead than charged after 20 minutes of charging. Several hours on a typical battery charger is needed, or up to 24+ hours on a battery maintainer/charger, to actually bring the battery up to full charge. Unlike lithium batteries, lead-acid batteries are only 'happy' when fully charged, and will suffer immediate and/or gradual damage if not fully charged. Given the way these batteries are used in the Leaf, you wouldn't necessarily know a battery was about to fail, because there is no 'stress test' like cranking over an engine to warn you of its impending demise. That's why many of us use battery maintainers once a week or more to keep the accessory battery charged at least above 80%.

 

[Stanton]

Just "get the lead out guys": replacing the stock lead acid battery with a Lithium ends all these dead battery problems. Read my blog post (now that I have transferred everything to the new blog site).

http://stanton.myevblog.com/2012/01/16/getting-the-lead-out/" onclick="window.open(this.href);return false;

 

[KillaWhat]

Just "get the lead out guys": replacing the stock lead acid battery with a Lithium ends all these dead battery problems. Read my blog post (now that I have transferred everything to the new blog site).

http://stanton.myevblog.com/2012/01/16/getting-the-lead-out/" onclick="window.open(this.href);return false;

Sounded cool.

...........$841.00 ?????

 

[MikeD]

Two questions (for any 2013 Leaf owners who have observed either action):
1) If the car is left in "ACC" mode for about 1 hour (and not charging or plugged in), does it automatically change to "OFF" mode?

I can say my 2011 Leaf always does this (when I am listening to the radio).

2) If the car is left in "ON" mode (and not charging or plugged in), does the car start charging the 12v battery (probably when the battery voltage drops below a certain threshold)?

I can say my 2011 never does this (I leave a voltmeter connected to the instrument panel's 12v power outlet that monitor's that voltage), but the 2013 Owner's Manual seems to say that year Leaf will, and I seem to recall at least one 2013 owner confirming this. (See page EV-5: "...While vehicle is driven -- The Li-ion battery charges the 12-volt battery as necessary when the power switch is in the READY to drive position or ON position. ...").

I can also say that I regularly run the 12v battery down below 12.00v or so in "ACC" mode (and then usually recharge in "READY" mode until the charging level drops from ~14.5v to ~13.1v according to my attached voltmeter), but have never had problems with that battery (30 months of use now).

 

[TomT]

Exactly. There is virtually no ROI there...

Sounded cool. ...........$841.00 ?????

 

[Computerizer]

Due to Nissan's questionable logic, that means the 12v battery would have been on its own, with no chance of being recharged from the traction battery. So it seems it has to be either a bad 12v battery or some pretty hefty drain on it. Anybody see any logic errors yet in my thinking?

Everyone keeps saying this but I actually disagree. According to the manual, the third indicator light on the dash with flash when the 12V battery is charging. I have seen it flash while the car is sitting in the garage.

When the EV (Electric Vehicle) system is off for an extended time, the 12-volt battery may be automatically charged for a short period of time on a regular basis.

Also, this vehicle was NOT PLUGGED IN when the battery died. It was plugged in for just a couple hours after charge completion, then I took the charging cable to plug in my 2012 instead when I got home from work.

or something (ELM327 maybe) plugged into the diagnostic port sending commands.

Indeed, my ELM device was plugged in to the vehicle at the time. I always leave it plugged in to my 2012's port without issue. We'd just gone on a 1,300 mile road trip with the 2013, and the device was plugged in the entire trip and for several days afterward when this happened.

I suspect that it was the ELM that drained the battery but it would be pretty crazy for it to be able to use as much energy as is stored in the 12V battery overnight -- seems like it would have had to melt itself.

 

[TomT]

I've measured the current draw of mine and it is about 80 milliamps... That's about one amp-hour over night so it definitely should not be a consideration...

I suspect that it was the ELM that drained the battery but it would be pretty crazy for it to be able to use as much energy as is stored in the 12V battery overnight -- seems like it would have had to melt itself.

 

[Stanton]

Exactly. There is virtually no ROI there...

Sounded cool. ...........$841.00 ?????

It's NOT $841, and there IS an ROI when you don't have to replace your 12v battery for 5+ years.
You need to look further than $$ on some of these things; after all, everyone on this forum spent (at least) $35k on a car that won't even go 100 miles :roll:

 

[TomT]

I fully expect to still have the original battery when I turn it in at the end of my four year lease... So, no ROI for me...

there IS an ROI when you don't have to replace your 12v battery for 5+ years.

 

[LeftieBiker]

I have "Greensaver" lead-silicone batteries in my scooters, and think it might be worth considering using one of those in a Leaf. The advantage is that, with no sulfur (supposedly) in the electrolyte, the batteries allegedly don't suffer from sitting around partially discharged. (They are still damaged by complete discharge.) One of my scooters is dead and possibly for good, so that leaves me with 5 good 38AK 12 volt lead-silicone batteries...

 

[voganni]

Well I guess this is as good a place as any to relate the latest in my battery drain saga. My 2013S has tried to run its battery dead so many times I've lost count. I catch it in the act now with my battery tender, which I hook up after each charge, or during. If the light doesn't go from red to green, the car is drawing more power than the tender can put out. My Leaf will go to .98 amp parasite drain when it "wigs out" (my wife's name for the issue). Only disconnecting the 12v for a bit will reset the car, usually for a couple weeks or so.

The car did it in Seattle, close to a dealer finally, so I took it in. I told the service manager "I'm not trying to tell you how to do your job, but if the battery is disconnected for even a second, it will reset to normal." So a couple hours later, the tech who worked on it comes up and says "Can't find anything wrong with your car. Parasite drain after 20 min. is only 15ma, 12v battery checks OK." I said "Can you check the parasite drain without disconnecting the battery?" He says "No, we have to disconnect the battery to hook up our battery analyzer." Then he gets a sheepish look on his face and says something like "Oh, Bob did say something about not disconnecting the battery..........)" So, a perfect diagnostic opportunity is blown.

The tech did bring the car back in and do the software upgrade, although my car should have already had it. This was on Dec. 13. So far all is still normal, after numerous public charging sessions, 4 quick charge sessions, and routine home charging. Only time will tell.

There is something going on with these cars. Mine always starts after a charging event. My next purchase will be a DC clamp ammeter (the dealer in Seattle did not have one) if the problem recurs. I'll take it to the dealer with me and show them the .98 amp drain and give them the meter to test with! I love my Leaf, even more after successfully completing a long road trip. But I'd sure like to see some resolution to my battery problem. If a software update is the fix, that'd be great.

 

[LeftieBiker]

In the meantime, you might want to replace the 750mah battery tender with a Diehard or similar 2 amp maintainer/charger. That way it will handle the drain if you aren't around.

 

[Nubo]

It's NOT $841, and there IS an ROI when you don't have to replace your 12v battery for 5+ years.
You need to look further than $$ on some of these things; after all, everyone on this forum spent (at least) $35k on a car that won't even go 100 miles :roll:

I applaud your trailblazing. There's definitely a ROI if one avoids the hassle of a service-call, having to get a jump or tow, or suffering from some of the wierder symptoms of low 12V battery that have been reported (e.g. brake malfunctions). That's why I sprung for a replacement battery myself, as it didn't seem that the OEM would survive 3 years or even 2, given my usage patterns. In addition to that I've had a serious aversion to liquid electrolyte ever since my VW Beetle days. Replacing a couple of floor pans will do that. :roll:

That said, I couldn't quite pull the trigger on a Lithium replacement at this stage. But I'm glad it's working for you and will be interested in how it holds up long term.

 

[elmobob]

I had to get my 12v battery replaced under warranty a few weeks ago as well. I have a 2012. Once the weather got cold the car could not go to ready mode in the morning.

 

[oscar]

Yesterday morning my wife took her 2013 to town and back, and plugged it in when she got home. Several hours later, we unplugged it and plugged in the 2012 instead as we'd taken it to town in the afternoon.

This morning I went out to get something from the 2013 and found that the 12V battery was completely dead. Nothing in the car was alive at all -- no lights, couldn't turn it on, etc.

I jumped it with the 2012 and it's now sitting in the garage in "READY to drive" for at least 20 minutes, as the manual states in the jumping instructions, to charge the 12V battery back up.

Any idea what could have caused the 12V battery to die in less than 24 hours? There were no lights on in the car or anything, it was just sitting there.

Most of you remember I had my 12V battery die last year. I had it replaced by Nissan and it been working great. Before my the 12V battery replacement my car did lots of weird things. I notice when the 12V battery at low state of charge, I push the Start button 5 times then it let me start the car. Once it's in start mode, I put it in reverse and for that 1-2 second I couldn't use my brake. Almost hit a kid. So my advice to anyone with a dead 12V battery, get it replace does weird thing when it in low state of charge.

So looking back did the low 12V battery just let me start the car. After that it lost some kind of control that splits seconds that I couldn't use my brake. Anyway don't wait to long to replace your dead 12V battery. I would not jump start it many time, get it replace. Nissan came back with a report that my 12V battery was faulty and main cause that I was experience all the issues I reported.

Good Luck, be safe replace 12V battery.

 

[UBUYGAS]

Does the DC to DC charger only charge the 12V battery at the end of a 100% charging cycle?

Maybe that's the issue here? Everyone with 12V battery problems always charge to 80% ?

I haven't had an issue yet (knock on wood) and draw a lot more current than most with my 1000 watt stereo but I charge to 100% at least 5 times a week.

 

[RegGuheert]

Does the DC to DC charger only charge the 12V battery at the end of a 100% charging cycle?

Maybe that's the issue here? Everyone with 12V battery problems always charge to 80% ?

No, the DC/DC converter "charges" the 12V battery whenever the LEAF is charging or in READY mode (and intermittently under some other conditions). But I put the word "charge" in quotes since it typically spends too little time actually charging the battery (14.4V) to completely top off the battery, which is required for proper lead-acid battery health. Instead, the battery is normally held at "float" condition (13.1V), which neither charges nor discharges the battery. (Note that 13.1V *will* charge the battery if it is at a very low state-of-charge. That is why many of our batteries tend to sit around at about 60% SOC.)

I haven't had an issue yet (knock on wood) and draw a lot more current than most with my 1000 watt stereo but I charge to 100% at least 5 times a week.

No problem with the stereo. The DC/DC converter in the LEAF is extremely powerful, fast and accurate. As a result, it can hold the 12V battery wherever it wants to (unless the battery is shorted), even under heavy and varying loads. Unfortunately, I don't think it is programmed to produce output voltages that ensure good 12V battery health.

 

[DarkStar]

12 volt lead-acid batteries prefer to be floated around 13.8 volts (without gassing) and will sulfate if they sit below 100% SOC.

With the plethora of 12 volt battery issues though, I suspect that maybe our batteries were ordered too far in advance by Nissan and were already sulfated when installed, but since we don't use a starter motor, never noticed that it was an issue until further out. I've performed a 100 amp load test on my battery a few times and it indicated that it was right on the line of needing replacement, dipping to 11.9 volts after a 10 second load (11.5 is right about the cutoff for the voltage under load), however my battery hasn't gotten any worse over the last year.

Has anyone that has received a battery replacement taken any voltage readings after it has been in service to see how it compares to their old battery?

 

[Stanton]

Unfortunately, I don't think it is programmed to produce output voltages that ensure good 12V battery health.

Unless you replace it with a (properly designed) LiFePO4 battery

 

[Nubo]

With the plethora of 12 volt battery issues though, I suspect that maybe our batteries were ordered too far in advance by Nissan and were already sulfated when installed

That would be surprising, given today's Just-In-Time manufacturing techniques. On the other hand it does seem odd that there would be so many "defective" 12V batteries. I still suspect deep-cycling is at the root of many of these failures but then again we have people whose problems seem to have resolved after replacement.