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I have been reading lately that testing has been done on the life of Lithium-Ion batteries compared to their charging regime. These tests show that limiting the charge to 70-80% of battery capacity extends the life of the batteries dramatically. Nissan does not mention this is the owner's manual for my 2018 Leaf 40. There does not seem to be any easy way to limit the charge to a percentage on this model. My Tesla buddy only charges his S to 80%. So did Nissan miss this seemingly important item? Or maybe the Leaf's battery is immune (not likely)? I do not need the range of the Leaf 40 most of the time, as my commute is 50 kms each way. So perhaps I need to set the timer to limit the amount of charge each time. Arghh that's too much math every day. Any ideas?
 

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Evezy £50 code - cada7
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The LEAF actuary had the option to limit to 80% up until late 2015/early 2016. I'm still not entirely sure why they removed it. (Then again there's a lot of things Nissan have done with the LEAF which I can't help but question what they were thinking!)

I'd recommend you setting the charge timer anyways, especially now we are approaching winter. If you can make it so your car is still charging by the time you need to unplug and leave, the battery will have a bit of heat in it from charging still. Using a battery in the cold affects performance. Since there's no thermal management in these cars you ideally want to avoid extreme temperatures with it, both hot and cold.

The battery chemistry has improved several times since the original LEAF in 2011. That mixed with the increase to range and battery capacity probably means a few % of degradation isn't as important and hence the lack of 80% limiter. That's my only guess I can make really.

With all of that said, I'd probably consider the 100% charging is only really harmful if you are charging to 100% and then leaving it fully charged for a long time. If you're using it daily I wouldn't be so concerned at all. Same goes with the bottom end of the battery too. Don't leave it very low on charge for a long time either.
 

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I have been reading lately that testing has been done on the life of Lithium-Ion batteries compared to their charging regime. These tests show that limiting the charge to 70-80% of battery capacity extends the life of the batteries dramatically. Nissan does not mention this is the owner's manual for my 2018 Leaf 40. There does not seem to be any easy way to limit the charge to a percentage on this model. My Tesla buddy only charges his S to 80%. So did Nissan miss this seemingly important item? Or maybe the Leaf's battery is immune (not likely)? I do not need the range of the Leaf 40 most of the time, as my commute is 50 kms each way. So perhaps I need to set the timer to limit the amount of charge each time. Arghh that's too much math every day. Any ideas?
I don't think you need to worry. There is related information here.
 

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Ryan of EV Opinion mentions this in his 50,000 mile review of his Leaf. Jump to about 7:30 if you don't want to watch it all (although it's pretty interesting!)

 

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I'm concerned about this too. I recently bought a 2013 Fluence, which now has a range of 64 miles. :)

That's just about okay for me, but I don't want it to go down further. I suggest you work out your weekly mileage, work out how many kwhs you need for that, then charge one seventh of that every day, using the timer.
 

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When you use anything, it wears out. Maybe imperceptibly, but it does. There’s no way around it.

Covering your new sofa with plastic, or putting rubber mats over your hallway carpet also limits wear, but possibly limits the aesthetics and pleasure of ownership.

Li-ion batteries (all batteries for that matter) gradually ‘wear out’ as you charge and discharge them. That’s life.

I find people worrying about battery charge % on a car they most likely use everyday very strange. I’m struggling to think of any other consumer item we try to baby quite as much.

If Nissan haven’t mentioned it in the manual, I’d let them and the warranty worry about it. I’d use my car the way I want to, using all of the advertised range thanks very much.

I think battery tech is such that the degradation is much reduced from the early days, much has been learnt about battery management. They now generally speaking hide a top and bottom buffer of capacity outside of the advertised and accessible.

The early Leaf has a lot to answer for in instilling this sense of fragility about car traction batteries!
 

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When I received my Kia e-Niro back in April 2019, because the manual said little about charging, I contacted Kia to get their take on charging to 100% and 80% on rapid Charge. They said their warranty of 7 years covered the battery and there was no need to charge to 80% on my home 7kw charger. If the manufacturer says that, that's what I do and so should you.
 

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A recent video in, I think, EV News Rides Again thread, had a Tesla S/M3 owner/blogger talking to a Tesla techhy about the displayed range available, which had been fluctuating due to a bit of a software bug/feechur. As part of the investigation, Tesla analysed his degradation, and said it was one of the lowest they'd seen on that model & mileage. The owner explained that he advised his followers to charge & try to stay inside the 20% - 80% range whenever possible. Tesla techhy said that that's what Tesla were finding, and agreed with the owner about this being a wise policy.

Previous analysis of Li-on batteries has shown that leaving them at 0% or 100% for long periods of time, e.g several days continuously, damaged the batteries more than leaving them in the 50% -ish charged state. The general advise was, use the full 0% to 100% range if you need to, but just don't leave the car sitting there in that state. Charge to 100% & depart asap. And refill quickly after emptying the battery.

Recent tech is bound to be improving, but I supect the same degradation behaviour is there to some degree. Bottom line - the gentler you treat it, the longer it will last.
 

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The LEAF actuary had the option to limit to 80% up until late 2015/early 2016. I'm still not entirely sure why they removed it. (Then again there's a lot of things Nissan have done with the LEAF which I can't help but question what they were thinking!)
I think the option was removed because it affected the range that Nissan could advertise in the USA. I still try to charge to 80% when more is not needed by a careful use of the timer.
 

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So, let me get this straight.

Some of you are suggesting that effectively not using 40% of your battery capacity is the way to hope that you avoid degradation somewhere down the line?

For what purpose, so that you can claw back some of the inconvenience down the line?

I thought the Tesla example was due to them letting folks use ‘all’ of the battery if they wanted? I believe even that’s changed now with their adoption of buffers top and bottom.
 

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This is on my mind as well. I don't like leaving it fully charged for very long. When I go on holiday, I try to leave it at 40 - 70%.

I was thought that Nissan had all of this battery management in built.

It's another inconvenience of owning an EV. It's something that the media or ICE owners don't seem to know about.
 

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Just charging to around 80% leaves room in the battery for some regen into the battery so lower consumption figures can br achieved. Regen cannot happen when the battery is full and limited when close to full.
 

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So, let me get this straight.

Some of you are suggesting that effectively not using 40% of your battery capacity is the way to hope that you avoid degradation somewhere down the line?

For what purpose, so that you can claw back some of the inconvenience down the line?

I thought the Tesla example was due to them letting folks use ‘all’ of the battery if they wanted? I believe even that’s changed now with their adoption of buffers top and bottom.
No, I think the suggestion is to keep that car at say 40-80% SOC during normal daily use and then charge to 100% only when needed.

With cars that provide this functionality it’s no hardship to do. Although I agree it’s only going to make marginal improvements to the degradation over time.
 

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Evezy £50 code - cada7
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It is worth remembering that some EVs such as the i3 require the battery to be charged from time-to-time for cell balancing purposes.
The Zoe is a other that makes a big deal out of cell balancing. But really I think that all EVs should get a full charge and discharge maybe once a month. Even if the every other day of that month you're running between 80 and 20.

With many cars if you run them 80-20 all the time and never do the occasional full charge and discharge you'll gradually find the range you have to play with between 80 and 20 falls. I've been called out to take a look at a 24kWh LEAF which had complaints about significant degradation despite having all its capacity bars still. I disabled the 80% limit, started with 100% and went for a long motorway run. A few rapid charges and discharges later I returned it to the users who reported their usable range even with the 80% limit enabled again was giving them an extra 10-15 miles depending on use and weather.
 

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The Zoe is a other that makes a big deal out of cell balancing. But really I think that all EVs should get a full charge and discharge maybe once a month. Even if the every other day of that month you're running between 80 and 20.

With many cars if you run them 80-20 all the time and never do the occasional full charge and discharge you'll gradually find the range you have to play with between 80 and 20 falls. I've been called out to take a look at a 24kWh LEAF which had complaints about significant degradation despite having all its capacity bars still. I disabled the 80% limit, started with 100% and went for a long motorway run. A few rapid charges and discharges later I returned it to the users who reported their usable range even with the 80% limit enabled again was giving them an extra 10-15 miles depending on use and weather.
Who'd have thought eh? Sounds like the memory effect on Nicad phone batteries. I wonder if the problem was the software getting confused rather than a problem with the actual battery?
 

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That early design the Volt had a 16.7kWh battery and only 60% (10.2kWh) usable, It charges to a nominal 80% though it is presented as 100 ;). It appears this worked and works and users see no degradation over years of use. Even the one thats done 400,000 miles plus and seemed to have battery failure turned out to be electronics failure, its linked on here somewhere.

Looks like GM got something right a decade ago.
 

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That early design the Volt had a 16.7kWh battery and only 60% (10.2kWh) usable, It charges to a nominal 80% though it is presented as 100 ;). It appears this worked and works and users see no degradation over years of use. Even the one thats done 400,000 miles plus and seemed to have battery failure turned out to be electronics failure, its linked on here somewhere.

Looks like GM got something right a decade ago.
They did, and most manufacturers are doing something similar, albeit with smaller buffers now. I think it’s fair to say that the GM solution was possibly over engineered.

The e-Golf lets you access 90% of the pack capacity, even when it’s full it’s not.

Is there a manufacturer out there now who isn’t doing something similar?

It seems to me that people are trying to assist or second guess the Battery Management System, who knows if you’re actually helping or making things worse.
 

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e-Golf lets you access 90% of the pack capacity, even when it’s full it’s not.

Is there a manufacturer out there now who isn’t doing something similar?
Didn't the Mercedes B250E give the user the opportunity to pick if they used the entire battery or not? You could charge to what they called 100% but also had the option to enable something called RangePlus or something like that, which allowed them to charge the battery to the true 100% if you were needing that extra range. Especially on a car like that which couldn't rapid charge and only managed 3kW charging on single phase, I can imagine why such a feature existed there.

I don't think there's anything that allowed the user to constantly charge all the way to full though. Not only is it going to accelerate battery wear but it will make all degradation immediately noticeable. At least with the buffer most cars which aren't LEAFs won't have any major range loss issues until the warranty is long expired.
 

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Did you guys ever see the Renault Youtube clip where they discussed this? Renault apparently automatically release futher capacity remotely when they notice the range dropping.
 
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