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Not a big deal but I've noticed that when I set my overnight charge timer to 80%, the next morning I turn the car on the find 79% of charge available.

Anybody else noticed this? Is my battery buggered? :p
 

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I haven't got mine yet, but what happens if you set it to 81%? I know you shouldn't need to do that but it might be a way around it?
 

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I charged to 80% at a rapid yesterday, and then didn't return to the car for a couple of hours (RCN launch), and when I hopped in it had dropped to 78%. I think this is just normal behaviour to drop a couple of points after the charge ends :)
 

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I haven't got mine yet, but what happens if you set it to 81%? I know you shouldn't need to do that but it might be a way around it?
Unfortunately it's not that flexible as the only options are 80% or 100%. Nice idea though ;)

I charged to 80% at a rapid yesterday, and then didn't return to the car for a couple of hours (RCN launch), and when I hopped in it had dropped to 78%. I think this is just normal behaviour to drop a couple of points after the charge ends :)
I think you are correct, I'll imagine the battery 'getting settled' after a charge which results in it sinking slightly.
 

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I find setting the charge timer is a good way around this, if you set a start time, and not an end time, just aim for about 90-120 minutes less than what it quotes for 100%. Having said that, I'm now happy to leave it to 100% otherwise I forget to switch off the timer, or switch off long life mode, and next time I charge it stops early. :rolleyes:
 

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I only charge to 100% now that I have lost about 15% of my range. If I just charge to 80% I can't now safely do the 50 miles to my nearest rapid.
 

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Hi Paul,
I can easily still do 50 miles - though your area may be more hilly. That being said full charge on my MY2012 (made in 2011) is around 241 gids now, suggesting a degredation of around 14% assuming full gids at 180. It's also down to around 57.5 Ah which on a baseline of 64Ah suggests 10% degredation. Let's call it 12% ......

However my driving has improved, and feedback has improved. That does mean having to drive slower (though I don't go <60 on motorways generally except for 1/2 error situations- not safe IMO)
 

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My 100% charge is down to 236 GIDS after 32,000 miles and 400 rapid charges :( I am expecting to lose the fist bar of capacity any time now.

My average efficiency is 3.5 miles/kWh giving a max charge of 18.8kWh and a theoretical range of about 66 miles. 80% would be 52 miles... too close for comfort to get to the rapid so I always charge to 100% now :)

Still well within expectations though so no complaints but it does mean you have to change your expectations as time goes on.
 

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My 6 month old Gen2 (<5k miles) has been doing this for a few weeks now, and is now with Nissan MK to diagnose if there's an issue.

If long-life mode is disabled it charges to 100% (not 99%), but with long-life enabled it only reaches 79%.

They say the batteries are fine but cannot tell me if this is "normal" or within expected tolerances of degradation. I would say not after 6 months/5k.

They are now working with the Nissan HQ tech guys on the readings given by the car as they don't know how to resolve it.

Awaiting a further update from them.
 

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I think it's totally normal, and part of the reason why the first gen cars don't give you the % reading at all, just 12 bars, it introduces some fuzziness.
 

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Maybe, but by removing the fuzziness and introducing a numerical scale now raises alarm bells, and causes confusion to the poor guys at the dealers trying to figure out why an 80% charging threshold stops at 79%, but 100% tops it right up.

Maybe it's just a rounding error and needs a s/w patch.
 

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My guess is that it stops bang on 80% It then falls back to 79.99% when the voltage lowers when the charge is stopped
 

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As already pointed out the cut-offs are pretty immediate - it only has to touch 80% to stop, it can then drop back to 79% if you just sit and watch it a few minutes.
I think 100% is a bit different as
1) it is artificial based on where the battery management system thinks it can safely go to, and
2) there is a certain amount of balancing takes place at the top end, I understand, which may give a "more robust" 100% figure
 

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That is one of our theories too but only started doing this recently. Used to stop at and display 80%.
It used to be warmer outside! Reported SOC will fall as temperature drops, and the battery will start dropping in temperature as soon as charging stops.
 

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So report back from Glyn Hopkin in MK via Nissan technical:
"Showing signs of slight wear but 1% degrigation [think they mean degradation] caused by LBC unit, PDM unit and VCM unit converting battery charge to charge %. Nissan advised the wear is minimal and nothing for the customer to be concerned with".

So 1% loss after 4500k miles using power save mode for majority of charges.
:(
 

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So report back from Glyn Hopkin in MK via Nissan technical:
"Showing signs of slight wear but 1% degrigation [think they mean degradation] caused by LBC unit, PDM unit and VCM unit converting battery charge to charge %. Nissan advised the wear is minimal and nothing for the customer to be concerned with".

So 1% loss after 4500k miles using power save mode for majority of charges.
:(
The 80% does not and never did mean "80% of new capacity" it means "80% of the battery's current capacity". So once your car is 10 years old with only 70% of its as new capacity an 80% charge will mean 80% of that 70%.

At six months old your actual degradation is probably over 1% already, 2% is quite possible. You can connect a LeafDD or leafspy dongle to check the actual condition.
 

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Not a big deal but I've noticed that when I set my overnight charge timer to 80%, the next morning I turn the car on the find 79% of charge available.

Anybody else noticed this? Is my battery buggered? :p
Mine has almost never been at 80%, was 79% and now usually i see 78% since i've started charging overnight on 3.6kwh instead of 6.6, but i expect this is as people say, due to the voltage drop off after charging finished or the battery cooling which reduces potential watts available, either way LeafSpy will show if you capacity has dropped. Mine has done 15,500 miles and still showing 67.36 ahr on a 100% charge which is the same as when i picked it up with 20miles
 
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