12v Battery

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

CarPortal

Active member
Joined
Nov 28, 2015
Messages
41
Location
Northern California
I cannot seem to find what should be a simple answer to a simple question. 12v battery on 2014 Leaf S is dead. I reviewed Nissan's directions for jump starting the car which are pretty straightforward. So now it's "running" and drivable.

1 - Is the 12v battery being charged even when the Leaf is left on and in park in the garage? Is this an adequate (though probably inefficient) method to recharge the 12v battery? Its sitting now with all other systems off (AC, lights, radio).

2 - In order to test and then charge up the 12v battery with a regular 12v car battery charger what are the proper connections? positive/positive and negative/engine block like on a ICE? Or as I have read on various forums is it better to disconnect the battery from the car and connect it directly to the 12v charger.

Calling Nissan Leaf support was not too helpful.

Waiting to hear back from a tech at my dealer since the service advisor did't know.

My main concern is avoiding any damage to the car. I'm probably being overly cautious.

Thanks for your input.
 
Motarra said:
I cannot seem to find what should be a simple answer to a simple question. 12v battery on 2014 Leaf S is dead. I reviewed Nissan's directions for jump starting the car which are pretty straightforward. So now it's "running" and drivable.

1 - Is the 12v battery being charged even when the Leaf is left on and in park in the garage? Is this an adequate (though probably inefficient) method to recharge the 12v battery? Its sitting now with all other systems off (AC, lights, radio).

2 - In order to test and then charge up the 12v battery with a regular 12v car battery charger what are the proper connections? positive/positive and negative/engine block like on a ICE? Or as I have read on various forums is it better to disconnect the battery from the car and connect it directly to the 12v charger.

Calling Nissan Leaf support was not too helpful.

Waiting to hear back from a tech at my dealer since the service advisor did't know.

My main concern is avoiding any damage to the car. I'm probably being overly cautious.

Thanks for your input.

1. If you are trying to charge the 12V battery in car you want the car on, and run the windshield wipers on the slowest delay non stop. While running the wipers the inverter puts out much higher voltage and will charge the 12V quicker that way. You might have to spray some water on the wipers/glass first or use the wiper fluid occasionally to keep from shredding the wipers.

It may sound counter intuitive but the Leaf assumes if the wipers are on you are likely using the lights and radio and such and it pumps higher voltage into the 12V bus to offset the expected drain and it will keep that voltage high for several minutes after the wipers cut off to help the 12v battery recover. So if you run the wipers on the slowest delay but keep the radio, lights, etc off it will charge quicker (assuming you are in Ready mode and it is running off the high voltage pack and not draining the 12V further).

2. You will be better off to some extent removing the 12V battery from the car to charge it but I'd just grab a CTEK 3.3 or 4.3 amp and plug it in without removing the 12v from the car. In a pinch a battery minder or lesser quality dumb charger will work for bulk charging but I prefer using a desulfating smart charger like the CTEK.

Oh and there is no Engine block. Ingineer advises "that the negative cable should not be connected directly to the battery. He suggested clamping to the big cable that connects to the DC/DC converter, but any grounded place on the car away from the battery should work fine."

Silly me, I've used the negative straight on the battery. I do however make sure the car isn't plugged into both an EVSE and a 12v battery charger at the same time. I either charge the HV battery pack or charge the 12v, I don't try to mix the two.
 
Don't mess around with "testing" the battery (same with wherever you take it): just replace it. It's not worth creating more problems with your Leaf. Might want to update your profile with location info (seems like you got decent life out of it).
 
I second the advice to just replace it. I'm finding, and reading, that 12v auto batteries are just not keeping up with the electrical demands required. Replacements are relatively inexpensive, and you can avoid the nagging concern about an unexpected, always inconvenient failure.
 
The contrary argument here is that some people's driving patterns don't fit at all well with the Leaf's questionable 12 volt battery charging algorithms, so replacing a dead battery in that case, with no other actions, would lead to... another dead battery. If you use the car mainly for short trips, especially at night or in cold weather, a battery maintainer might be needed.
 
They don't make batteries like they used to. That's the price of battery monopolies. Anyway, I bought a new 12v with my new/used 2012 Leaf as the original just wasn't doing its job. After four weeks and nine hundred miles, I hooked it to a battery tender and it took six hours to charge. Just another issue with this car where I wonder just wtf designers were thinking.

So I'll be performing a monthly 12v recharge. The car didn't fry by leaving the battery connected, so I'll just keep doing it that way.
 
So I'll be performing a monthly 12v recharge. The car didn't fry by leaving the battery connected, so I'll just keep doing it that way.

You can connect a hardwired lead for a battery maintainer to the battery. Just use a ground on the big "stack" of components in the motor compartment, instead of the negative battery terminal. And I suggest weekly top-ups, not monthly. I extended the maintainer lead, ran it into the charge port compartment, and can connect the maintainer as easily as plugging in the car. If you leave the car plugged in but not charging, having it connected to a maintainer then is pretty much a necessity.
 
jkline said:
They don't make batteries like they used to. That's the price of battery monopolies.

I am going to have to disagree, at least in my situation I'd have to say that the Nissan 12V battery has been excellent. I have a 2011, here it is almost half-way through 2016, and it appears to be fine. (Of course, now saying that I'll have minutes before battery failure?)

I'll also second the use of the CTEK charger as mentioned by dhanson865. I have been very happy with my CTEK US 0.8, which is a small 0.8 amp charger, which I leave connected to the Prius 12V battery, and on occasion plugging in overnight, to keep it in excellent shape. dhanson865 mentioned the CTEK Multi US 3300 charger, which is slightly higher priced but does have the option to charge at the low setting of the CTEK US 0.8 as well as 3.3 amps, which if I had known at the time I might have chosen the 3300.

I'll also say that the Ford Motorcraft battery I had long ago proved excellent also.
 
I have been using the ridiculously easy to use - "Battery Tender" for many years on all my cars. It is computerized, and will charge your battery to the right level, and then maintain that level indefinitely. You can leave is plugged in for months.

It comes with alligator clips to connect to the battery AND has permanently mountable "quick release" leads to both battery terminals and just plug the battery tender in with just a snap. just unplug the 1 connector when you want to go..

OK, nobody tell me that you cannot charge the leaf battery. I have been using it for 1 1/2 years every 2 weeks or so and the 12v battery is perfect.

PS - using this system, I have a 2006 car that still has a strong ORIGINAL battery in it....
 
powersurge: You have the battery-tender hard-wired to the battery terminals, and simply plug it into the charger as needed? I've done this on an RV, never on an automobile.
 
I just keep topping up the distilled water in mine, and have never had an issue. We tend to use the Leaf multiple times a day though, and that might be why ours hasn't had an issues with the battery yet. I have been debating just replacing the battery since it is 4 years old before I had any problems. If I did have any issues with it though I would just replace it. I have a battery tender myself, and it is a great device to have. Keep the battery topped up on our Chevy Cruze for whenever we want to use it.
 
sub3marathonman said:
I am going to have to disagree, at least in my situation I'd have to say that the Nissan 12V battery has been excellent.
I have to agree. I really like the design and construction of the OEM battery in our 2011 LEAF. I particularly like the translucent case which allows the water level to be checked without opening anything.

Of course the battery has used almost no water since the LEAF *never* overcharges the battery. Until about a year ago, it showed no sign of sulfation. Currently, it appears to be about 5% sulfated and I am trying to recover that lost capacity now.
 
RegGuheert said:
sub3marathonman said:
I am going to have to disagree, at least in my situation I'd have to say that the Nissan 12V battery has been excellent.
I have to agree. I really like the design and construction of the OEM battery in our 2011 LEAF. I particularly like the translucent case which allows the water level to be checked without opening anything.

Of course the battery has used almost no water since the LEAF *never* overcharges the battery. Until about a year ago, it showed no sign of sulfation. Currently, it appears to be about 5% sulfated and I am trying to recover that lost capacity now.
Thanks for the data point! And oh, look: an SL with the "useless" solar panel....
 
Levenkay said:
RegGuheert said:
sub3marathonman said:
I am going to have to disagree, at least in my situation I'd have to say that the Nissan 12V battery has been excellent.
I have to agree. I really like the design and construction of the OEM battery in our 2011 LEAF. I particularly like the translucent case which allows the water level to be checked without opening anything.

Of course the battery has used almost no water since the LEAF *never* overcharges the battery. Until about a year ago, it showed no sign of sulfation. Currently, it appears to be about 5% sulfated and I am trying to recover that lost capacity now.
Thanks for the data point! And oh, look: an SL with the "useless" solar panel....
I just reread what I wrote. My point was that I like the design of the battery, but I should have pointed out that the LEAF is not why my battery is not sulfated. I noticed it had sulfated about 40% after the first couple of years. Since then I have used a desulfating charger to try to recover the original capacity, which I had done as of last year. Now it is down just a bit. I don't know if that can be recovered or not. We'll see.

Yeah, the PV panel is pretty much useless on our SL, considering that it lives in our garage.
 
Take care of your Japanese battery. In the US, Exide and Johnson Controls make all of our batteries now. The quality is not what it used to be.
 
Yes I have always hard wired the quick release cables to the black and red terminals of the battery since my early days of motorcycling, so that I could easily plug in the battery charger without removing any covers to reach the battery.

I do the same with my cars, and it is an instant connection, with no danger of cross-connecting the polarities...

here is the battery charger I swear by... (I have 3 of them to keep my 5 cars in my family going strong, even when the cars are not used often...

http://www.amazon.com/Battery-Tender-021-0156-Charger-Model/dp/B000NCOKQK



PS - I also like the solar panel chargers that I get at Harbor Freight...

http://www.harborfreight.com/15-watt-solar-battery-charger-68692.html
 
Excellent. Thanks for the very clear post. I've got a slightly less sophisticated BatteryTenderPlus, but it should work just fine.

I'll be anxious to see how long it takes to bring my 16-month old, 9500mile battery up to full charge. Texas heat can kill batteries in short order, and I'll gladly be replacing with a larger capacity battery when a replacement is required.
 
Even a Battery Tender Jr, with a whopping 0.75 amps, will keep a Leaf battery charged if given long enough. I'm using one now, and it usually only takes an hour or two to top off my battery.
 
I second that - I use the following 0.8 amp charger:

http://smartercharger.com/products/batterychargers/ctek-us-0-8/

If I'm away for more than a few days I use it - the longest I used it was for one month.
 
Back
Top