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30KW Tekna (2017)
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Discussion Starter #1
Just had a call from my dealer, Leafy is back with 2 new cells.

Will pick up tomorrow and do a bit of a test! Cannot wait..... fingers crossed all is well.
 

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Leaf 30kWh, Outlander PHEV
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Check that the cells were balanced (doubt this) when replacing

Sent from my SM-G973F using Tapatalk
 

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Discussion Starter #3
Well I called before hand and was assured by Tony the service manager that they would be and they had all the equipment to do this.

We will see, I’m expecting there to be something wrong as things never go my way.
 

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Let's hope that your luck has changed! You deserve a break.
You should record the next few cycles on LEAFSpy, going from 100% to as low as possible at both top and bottom.
When you say cells do you mean that or modules?
 

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Discussion Starter #5
Oh I’m not sure, Leaf spy showed 2 weak cells but they come as cell pairs. The garage said they replaced 2 cells then sent me this weird email if you want to see it.......

Good afternoon,

The vehicle is now complete and we are arranging it to be brought back to your local Nissan dealership.

We have replaced the 2 weak cells that you had reported to be low. I just wanted to clarify that all of the cell voltages are not always identical voltages and this does not always indicate a fault. The lithium battery controller (LBC) will balance the cells when charging but not necessarily keep them at an equal voltage. It is normal for cell voltages to deviate and this has virtually zero difference on the range. The allowed deviation varies dramatically depending on battery state of charge (SOC). You may find cell voltages deviate much more at a low SOC but even out when fully charged. The LBC consistently monitors this and if it falls out of specification the HV warning light on the dash will illuminate.

We have checked the battery health and capacity and both are ok. Please note however the range shown on DTE (distance to empty) is often a lot higher than you can realistically get from a full charge. We have replaced 2 cells in his battery so we would advise to try a few charge cycles and see how the DTE may change, a charge cycle should consist of 100% SOC and draining the battery to a minimum of below 20% SOC then charging using a normal charger, this will give the most realistic range read out on the DTE.

In relation to your door mirror concern, I am afraid we have too many Leaf Battery commitments here at Nissan Gateshead to be able to look into this for you and I would advise you to ask your local Nissan dealership to take a look at this concern for you.

I hope this explains in detail the repairs we have carried out on your car.

Many thanks




Cannot wait to get in it tomorrow with LeafSpy!

Should I do a couple of 100% to turtle? Or is that too extreme?

Have already seen an absolutely stunning Zoe R90 Signature with the most beautiful cream interior, if they annoy me then bye bye Nissan!
 

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Should I do a couple of 100% to turtle? Or is that too extreme?
Too extreme, just follow the instructions in the email if you can manage it within your normal driving pattern and adjusting your economy accordingly to use the desired 80+% of charge. The key is to give the car the full chance to balance at the top end so leaving charging past when it gets to 100% until the charge lights go out (normally another hour on the LEAF.
Have already seen an absolutely stunning Zoe R90 Signature with the most beautiful cream interior, if they annoy me then bye bye Nissan!
Nooooooooooo! Don't go to the dark side! :eek: :eek: :eek: :eek: :eek: :eek: :eek: :eek: :poop:
 

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I'm not crazy, the attack has begun.
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The weakest cells should cycle from higher (open circuit voltage) than a stronger cell when full to lower than a stronger cell when empty.

I think what he is saying is that the cell management will not necessarily charge cells up to a maximum voltage so long as the weakest cells are getting to exercise from their highest to lowest values. So long as that is happening, the rest of the [stronger] cells doesn't really matter what they are doing.

He is then saying that the cell management gets to learn more about those weakest cells at lower SOC.

I am not aware that Leaf did this, I just thought it was a straight top-balance, but he seems to be saying something else there.
 

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The weakest cells should cycle from higher (open circuit voltage) than a stronger cell when full to lower than a stronger cell when empty.

I think what he is saying is that the cell management will not necessarily charge cells up to a maximum voltage so long as the weakest cells are getting to exercise from their highest to lowest values. So long as that is happening, the rest of the [stronger] cells doesn't really matter what they are doing.

He is then saying that the cell management gets to learn more about those weakest cells at lower SOC.

I am not aware that Leaf did this, I just thought it was a straight top-balance, but he seems to be saying something else there.
From watching mine, it seems to "learn" what are the lowest capacity cells at the bottom, and will do a bit of shunting into the lowest cells, but not simply top balancing everything - I think it's better to have a more consistent bottom end so you don't get a sudden turtle, than a consistent top end. Worst case for inconsistent top end is your charge finishes slightly earlier than expected (or the rapid charging reduces rate faster than expected).
 
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30KW Tekna (2017)
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Discussion Starter #9
OMG!!!!!!!!

Nissan have done a fantastic job! Cells balanced, already could tell the difference driving home, getting just over 1 mile per %!

Very happy but will do a test later to see range and hopefully recalibrate GOM with a couple of discharges then charges
 

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Good news! Of course now that you have greater range it'll be harder to use it all up and get an idea of where it settles, but a much happier point to be at.
 

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Discussion Starter #11
Just the mirror creak to try and get sorted now!!!

My partner says not too as when I buy my next car they will tell me they don’t want my custom if I pee them off!

LOL
 

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I'm not crazy, the attack has begun.
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From watching mine, it seems to "learn" what are the lowest capacity cells at the bottom, and will do a bit of shunting into the lowest cells, but not simply top balancing everything - I think it's better to have a more consistent bottom end so you don't get a sudden turtle, than a consistent top end. Worst case for inconsistent top end is your charge finishes slightly earlier than expected (or the rapid charging reduces rate faster than expected).
Yes, if it does that then it is better for the stronger cells, although it is simply a fact of life that any sort of 'passive' balancing will always more heavily load the weaker cells. The only way to avoid it is active energy re-circulation from the stronger cells during discharge, but people aren't that interested in those solutions because the problem just isn't widespread enough.
 

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Discussion Starter #13
OMG! I HAVE DOUBLE THE RANGE!!,

Just back from a good run from 100% to VLBW.

I am ecstatic to say I got 111 actual miles, driving without holding up traffic and safely. Average speed wa# between 55-62 mph.

Prior to the replacement I could only get about 60-70 miles with some speeds holding up traffic and my m/kw would never go above 4.

Usind D mode and eco, with some B mode when approaching stops, and it was an easy drive without too much having to baby the car.

The GOM performed flawlessly with a pretty accurate range, no sudden drops of battery percent etc.

I just checked and my m/kw was 5.1

So I’m well chuffed, currently on my granny charging back up.

Nissan may have a life customer if they keep up the good service as they have been excellent.
 
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