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Hi fellow Leafers!

I have just come back from trying to drive to the shops with my 2018 Leaf and the car won't do anything. The key fob won't open the doors, tried manually and got in the car but there's no response there either? Have tried changing the battery on the key fob but didn't solve anything. I'm now wondering if it's the 12v battery?

I read about inactivity being bad for the actual battery so I have been driving the car to the shops at least once per week so it doesn't really stay inert, which I thought would help.

Our Nissan dealership doesn't seem to be working fully as I can't get through, what should I do?

Thanks in advance!
Jump start it like in a Dino powered car then go for a descent drive.
If it’s still flat buy a new battery.
Many breakdown operators don’t realise you can jump start them and tow them unnecessarily.
 

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That is good to know, guess you wouldn't have a link for a good smart charger on the 12v DC battery anywhere?
I bought a cheap 4 amp smart charger (less than £25), a Chinese made product, but that eventually just stopped working, in less than a year (I used it once a week). So I then bought a NOCO Genius G3500, which is a better charger and is still working perfectly 2.5 years later (I still use it once a week - just connect it to the battery in the car, no need to remove the battery). The NOCO is designed in the USA but built in China. A quick search for the cheapest, showed that it can currently be bought for £42.50 off of eBay (I paid £53.95 for mine, including postage!).
 

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Discussion Starter #23
Lots of good advice here guys, thank you very much!

@Hitstirrer all you said makes complete sense and taking @dk6780 suggestion that all you need is to hit the brake and turn the car (thus 'turning it on' for driving) for half an hour would work I'd ask if this would be enough to do every week (or a couple of times a week) to charge the battery and avoid purchasing a charger?

Despite the advice of getting a basic charger being good, I am now inclined on investing on that CTEK smart one, however, if I can do without the expense then even better.
 

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..........................would be enough to do every week (or a couple of times a week) to charge the battery and avoid purchasing a charger?
In theory, it should be OK to use the car's internal top-up system, and energising the car every few days for a half-hour session may well stave off this mystery gremlin. Except that people have reported the problem when the car was only used intermittently and for short trips. Essentially that is the same as you suggest and has proven to not be totally effective.

I suspect that over the years OEMs have tweaked the systems to avoid this effect but obviously haven't confessed to that or thousands of owners of older cars would be demanding that their cars be retrofitted with that fix. For instance, deep in the settings menu of my classic Ioniq there is a feature called " Aux battery saver" which, when ticked, enables the DC to DC charger to activate if it detects a low 12v battery voltage and will engage the system up to ten times consecutively to top-up as required. The count is reset if the car is driven. This is designed to cover a car being parked at an airport for a couple of weeks.

Older cars do not have such protection and because only a small % of owners suffer the syndrome little has been done to help them. Which is why the debate over whether to engage in preventative maintenance or not has raged over the last five years.

On balance I went the route of charging the aux battery monthly, overnight, using a relatively expensive smart charger as they also condition and pulse charge as well as float the cells so that the battery is always in top health. And as well as not letting me down at inconvenient times, it would last longer and save money in replacements.

Many people advocate just buying a simple and cheap dumb charger as that will indeed recover the situation after a failure. And used with diligence it will also do the basic task of a smart charger. But even they must be bought with care because many do not have a 'switch-off' feature when fully charged and can cause damage if left on too long. A smart charger avoids that. Also, as reported by @keithr in #22 above many people complain that cheapies tend to let them down rapidly and they end up spending more in the end run.

Chargers like CTEK with a five year guarantee can actually give a lifetime of good service and provide excellent protection for the 12v battery which cheap chargers are not designed to do. ( There are other makes that offer identical features at a lower price - do your own research within your own budget )

At the end of the day, as always, it is a personal choice. You can decide to go to the car three times a week and energise it for a short time. For sure that will save money. And most likely work well enough. Or choose to buy a cheap trickle charger and worry about how long it will last.

I chose to invest in a decent charger and also a bit of extra personal time when doing my monthly tyre kicking routine. In return, I have peace of mind that the car won't lock me out or let me down due to low voltage in the 12v DC battery.

You choose which route works best for you.
 

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I bought a cheap 4 amp smart charger (less than £25) ... that eventually just stopped working, in less than a year (I used it once a week). So I then bought a NOCO Genius G3500
I should probably have also mentioned that the cheap smart charger only seemed to charge for about 30 minutes, but gave the impression that it had charged the battery. When I first used the NOCO charger it took about 7.5 hours to charge the battery, but from then on took less than that. Leaving it on for about 2.5 hours (once a week) is more than sufficient now. That implies that the cheap charger, and the car, weren't actually fully charging the battery.
 

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You don't want to fully charge the battery, it will wear out faster that way.

I expect the car uses the same dumb charger system, constant voltage. There are hundreds of thousands of fire alarm systems doing that with lead acid batteries for years and years all over the world.
 

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You don't want to fully charge the battery, it will wear out faster that way.
I thought that lead acid batteries lasted longer if you kept them fully charged (perhaps you were getting confused with Li-ion batteries?). From Wikipedia, "Sulfation can be avoided if the battery is fully recharged immediately after a discharge cycle", and from Battery University, "Recharge lead acid batteries after each use to prevent sulfation. Do not store on low charge".
 

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I thought that lead acid batteries lasted longer if you kept them fully charged (perhaps you were getting confused with Li-ion batteries?). From Wikipedia, "Sulfation can be avoided if the battery is fully recharged immediately after a discharge cycle", and from Battery University, "Recharge lead acid batteries after each use to prevent sulfation. Do not store on low charge".
That's right, but over-charging produces hydrogen that is vented. You want to charge the battery up but not over charge it, and smart chargers that eek every mAh out of the battery aren't good for that.
 

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That's right, but over-charging produces hydrogen that is vented. You want to charge the battery up but not over charge it, and smart chargers that eek every mAh out of the battery aren't good for that.
As aren't trickle chargers that continue to provide a low current even when the battery is fully charged. A "smart" charger should allow the voltage to drop to a float voltage and then cyclically raise it slightly to reduce sulphation.

 

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As aren't trickle chargers that continue to provide a low current even when the battery is fully charged. A "smart" charger should allow the voltage to drop to a float voltage and then cyclically raise it slightly to reduce sulphation.

Should do I guess, but constant voltage is proven and cheap.
 

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Lead acid batteries can be held at float charge voltage indefinitely and should not overheat or generate gas when doing so. That's between 13.5 and 15 volts, and is what most smart chargers attempt to offer to the battery all the time.
Smart chargers are very good for maintaining lead acid batteries, if you buy the right ones.
 

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I have a lead-acid power pack for my telescope, and had to buy a new one when my previous one failed to charge at all after it completely ran down. It became just a very weighty brick. Presumably all lead-acid batteries are the same. I make sure to charge the current one at regular intervals to make sure it's topped up.

Not really the same problem with a car I suppose, where it will be charged regularly by the system.
 

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I have a lead-acid power pack for my telescope, and had to buy a new one when my previous one failed to charge at all after it completely ran down. It became just a very weighty brick. Presumably all lead-acid batteries are the same. I make sure to charge the current one at regular intervals to make sure it's topped up.

Not really the same problem with a car I suppose, where it will be charged regularly by the system.
There are ones that can be deep discharged but yes normally it kills them.
 

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Even deep cycle lead acid batteries are not immune from degradation when discharged, they're just not as bad as traditional flooded cells (3-5x the cycle capacity). You really need a different type of battery chemistry to avoid that altogether, though all batteries have finite power cycles in reality.
 

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Sometimes I do, but not now. I'm confident that you can't find a lead acid battery that's genuinely oblivious to deep discharge no matter what its construction, they just offer degrees of degradation from "a lot" to "not so much".
 
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