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Since I am retired there is no need to use the car (Leaf 24/3kW charger) everyday/s, so thought that rather than leave it standing with something between 20 and 80%, I am charging it for 20 minutes everynight to keep it active. Wondering if this might be bad for the battery or it makes no odds.
 

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I would work out your weekly energy consumption, then aim to charge for one seventh of that every night, but obviously keep it around the 50% mark.
 

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Since I am retired there is no need to use the car (Leaf 24/3kW charger) everyday/s, so thought that rather than leave it standing with something between 20 and 80%, I am charging it for 20 minutes everynight to keep it active. Wondering if this might be bad for the battery or it makes no odds.
I would suggest you check battery charge % using app if possible.

If you don't forsee any use the next day and battery is near 50%, leave it as is. If its under 40%, charge it to 50% (1 hour at 3.3kW).

No need to charge it every day even if it is only for a little bit

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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The leaf uses a NCM 523 battery cell. As with all lithium batteries a charge to 90% is best for longevity. The Battery Management System (BMS) ensures this happens (at least on the 30Kw Leaf) automatically, there really is no need for the owner to try and set this up for themselves.

I just plug mine in to the 7kw charger overnight unless I have done less than 20 miles the previous day or I need a full charge the following day. The BMS system takes care of the rest and stops when it is done.
 

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The BMS system takes care of the rest and stops when it is done.
LEAF 24/30 BMS is not very good. Do not trust it to do the right thing. Do not plug the car in if it is already in a high state of charge.
 

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o thought that rather than leave it standing with something between 20 and 80%, I am charging it for 20 minutes everynight to keep it active. Wondering if this might be bad for the battery or it makes no odds.
NEVER plug the car in if the battery is at or above 98%. This will damage the battery.
Always plug the car in if the battery is under 20%.
Occasionally let the car charge all the way to 100%.

NEVER let the car sit for days or weeks above 90% or below 20%.


If you can, charge the car during off-peak times. Midnight to about 5AM is good.
 

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Could definitely be a thing with me if I finally do get an EV. I average about 50 miles a week. A year or so back I was talking to a couple in Sainsbury's car park who had 2013 Leaf. They charged once a week to 80% and never let it drop below 20%.
 

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People get a bit paranoid and over the top about this, like I said, BMS systems are very good at keeping the battery in a stable state. The batteries are just super-sized batteries similar to your mobile 'phone or your drone or e-bike- it's exactly the same technology employed.
I always charge my e-bike to 100% and am still on almost the same distance as when new some 4 years ago. Even if I have only gone 10 miles or so, I plug it in an it makes zero difference to the longevity of the battery.
There is nothing special about the Leaf battery, it is just the same technology, do not be over-concerned about overcharging it-you can't.

Tony (electronics engineer since 1969)
 

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There is nothing special about the Leaf battery, it is just the same technology, do not be over-concerned about overcharging it-you can't.
Actually you can. LEAF 24/30 BMS is stupid.


LEAF 24 and 30 have a very small margin safety margins at the top and bottom of charge. Letting the car sit below 20% SOC will damage the battery. Letting the car sit at 100% SOC will damage the battery. On top of that the BMS is truly stupid about overcharging. Unless you've set a timer, it starts a charge every time you plug it in. It then runs a balance cycle no matter what. If you plug in the car when it is at or above 98%, the car will overcharge, damaging the battery. There are warnings in the owners manual and a specific exclusion in the battery warranty.



Owners and even Nissan dealers have ruined batteries.

Here is a scan of the battery warranty exclusions from our 2014 LEAF.


124626
 

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People get a bit paranoid and over the top about this, like I said, BMS systems are very good at keeping the battery in a stable state. The batteries are just super-sized batteries similar to your mobile 'phone or your drone or e-bike- it's exactly the same technology employed.
I always charge my e-bike to 100% and am still on almost the same distance as when new some 4 years ago. Even if I have only gone 10 miles or so, I plug it in an it makes zero difference to the longevity of the battery.
There is nothing special about the Leaf battery, it is just the same technology, do not be over-concerned about overcharging it-you can't.

Tony (electronics engineer since 1969)
Not debating you being electronics engineer but batteries being chemicals and all that, I'd go with what battery engineers say.

There is some permanent loss of capacity if stored at high voltage persistently. There is also age related capacity loss due to electrolyte degradation. It roughly mounts to 2-3% on an average.

I charge almost every night to 100% and we use it 70 miles or so every day now

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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Li-ion cells tend to have usable range between 4.2V and 3.3V

Leaf charges cells to 4.1V.
At 20% the cell voltage is 2.5V and its likely that Leaf allows cells to drop to 2.4V.

The drop in usable range is to reduce overall depth of discharge that tends to affect the cells the most.

For the most optimum capacity and life Li-ion should never be charged about 3.93V and DoD should be low.

Stable storage voltage for Li-ion is 3.7V

- Leaf 30 kWh
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I still think that Nissan software engineers who programme the BMS know what they are doing-it's really not that hard to get right. There was also a software update to the BMS, if there were severe problems, that would have been picked up by them.
All vehicle handbooks are specifically written to give (in this case Nissan) as much wriggle-room to get out of paying for warranty claims on the vehicle as they can legally get away within the framework of the law, and not a skerrick more.
Sorry guys, you may have more EV experience than I, but I know the way the world works, and
vehicle manufacturers in particular have their handbooks, brochures and all publicity scrutinised, every sentence and clause examined by very expensive corporate lawyers to ensure they are not liable for almost everything.
 

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While on the subject, a passing thought about the floods up North and ev's.
I wonder what sort of safety interlocks are present on Leafs in particular and EV's in general.

380v -400v with a massive current capability and a flooded Leaf? mmm.... just a thought when looking at the TV piccies on the news, how dangerous could they be?
 

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I still think that Nissan software engineers who programme the BMS know what they are doing-it's really not that hard to get right. There was also a software update to the BMS, if there were severe problems, that would have been picked up by them.
All vehicle handbooks are specifically written to give (in this case Nissan) as much wriggle-room to get out of paying for warranty claims on the vehicle as they can legally get away within the framework of the law, and not a skerrick more.
Sorry guys, you may have more EV experience than I, but I know the way the world works, and
vehicle manufacturers in particular have their handbooks, brochures and all publicity scrutinised, every sentence and clause examined by very expensive corporate lawyers to ensure they are not liable for almost everything.
You are giving Nissan more credit than is due. BTW AESC makes the pack not Nissan (part owners).

The LBC update was to correct the rapid loss reported by BMS. Its just software and there is nothing stopping by Nissan from resetting BMS to report better than is health.

Regarding question about water and flood impacting EV, the packs are sealed to prevent water entering inside. You are safer inside EV in flood than ICE as EVs do not need air.

- Leaf 30 kWh
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Companies have zero interest of doing anything right by consumers - just look at VW emissions saga, Leaf rapidgate (both caused and tweaked by software).

We all know how the world works.
BTW I'm a mechanical engineer turned software programmer (20 years) - I would like to think that I know a thing or two about how programming teams work.

Bottom line is as long as battery does not deteriorate below 75% during warranty they couldn't care less.

- Leaf 30 kWh
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I still think that Nissan software engineers who programme the BMS know what they are doing-it's really not that hard to get right. There was also a software update to the BMS, if there were severe problems, that would have been picked up by them.
Making assumptions without the facts to back it up is going to get you nowhere on a forum full of engineers.
 

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Nissan knew full well they are borderline overcharging at 100 % indicated. They even added a setting to stop the charge at 80% and told dealers to use it. Nissan took it back out only because the US EPA made Nissan change the Window sticker range to reflect an 80 percent charge.
 

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Nissan knew full well they are borderline overcharging at 100 % indicated. They even added a setting to stop the charge at 80% and told dealers to use it. Nissan took it back out only because the US EPA made Nissan change the Window sticker range to reflect an 80 percent charge.
I wonder how current crop Tesla, Polestar etc get away with slider (I suppose default is 100%) and they provide accurate range for chosen %

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 
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