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Hi
I posted a similar experience earlier in this thread, where I had one cell reported by LeafSpy as weak and around 200mv difference across the cells. I would find that the reported range would decrease in line with the mileage driven until it got below 70% or so (can't remember the exact figure) and after that the estimated range would plummet like a rock and driving 10 miles would take 30 miles off the reported range. I took the car to Westway Nissan at Mill Hill and they did a diagnostic test on it, after which it went back to Nissan UK for just over a week and the weak cell was replaced. It's much more predictable in terms of range now and the overall range has improved pretty much in line with the reported range and my expectations.

Steve
 

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Hi
I posted a similar experience earlier in this thread, where I had one cell reported by LeafSpy as weak and around 200mv difference across the cells. I would find that the reported range would decrease in line with the mileage driven until it got below 70% or so (can't remember the exact figure) and after that the estimated range would plummet like a rock and driving 10 miles would take 30 miles off the reported range. I took the car to Westway Nissan at Mill Hill and they did a diagnostic test on it, after which it went back to Nissan UK for just over a week and the weak cell was replaced. It's much more predictable in terms of range now and the overall range has improved pretty much in line with the reported range and my expectations.

Steve

Steve did it come back with exactly the same pack or was it a different unit and just swapped out?
 

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Tu[r]tle mode comes past 4% I believe.
For my 24kWh Leaf, Turtle mode (which I have not yet encountered) comes on at a lot less than 4% SOC. AFAIK, LBW comes on at 4 kWh left, VLBW comes on at 2 kWh left, the %SOC indication goes to ---% when there is about 5% SOC left (? 1 kWh left), and I have yet to experience the reduced power turtle mode even though once when I plugged into a DBT charger, the charging post said I had 0% left. By other accounts, turtle mode is just sufficient to allow you to pull in to the side of the road away from other traffic.
 

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Steve did it come back with exactly the same pack or was it a different unit and just swapped out?
The pack shows the same serial number and the cell 77 that was previously very low now shows in LeafSpy as four cells that are slightly higher voltage than the rest of the pack, my understanding being that the cells are in modules of four so it looks like a cell module has been replaced in the existing pack.
 

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2014 Leaf (24kwh) at just under 49.7k miles.

Bought used three days ago, pleased to see the 90.4% SOH.

Is there anything else to look at to guage the battery health or is the SOH readout enough to go on?
That looks good. Let's see how that looks after a months usage?

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

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That looks good. Let's see how that looks after a months usage?

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
I will post an update in a month or so(y) given the current situ I'm confident it'll be doing an awful lot of sitting around. I was pleasantly surprised by the numbers.

Would you expect that to potentially deteriorate once normal usage resumes? i.e. because the car has been sat at the dealership, not getting much use, are these initial readouts not necessarily to be relied on?
 

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I will post an update in a month or so(y) given the current situ I'm confident it'll be doing an awful lot of sitting around. I was pleasantly surprised by the numbers.

Would you expect that to potentially deteriorate once normal usage resumes? i.e. because the car has been sat at the dealership, not getting much use, are these initial readouts not necessarily to be relied on?
Don't charge it fully. I'm charging my Leaf for an hour or so max as needed. I'm keeping it close to 50% as I don't need to go further than local shops

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

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Would you expect that to potentially deteriorate once normal usage resumes? i.e. because the car has been sat at the dealership, not getting much use, are these initial readouts not necessarily to be relied on?
After some normal uses, I'd expect the SoH to come in line with other cars of similar age.

The SoH is just a guestimate by the Battery management system. The guesses are based on battery voltages when it is at full and near empty, so to get most accurate guesses, you need to allow the battery reach top and bottom a few times. Unfortunately this is difficult to achieve during a lockdown.
 

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The HX seems to be a better value to go off and shows that the SoH is a bit iffy after nissans BMS 'patch' :(
 

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For those interested these are shots of my battery health over the last 11months, i cant find the original shot but when i bought the car it was on approx 94% SoH @ 24,000 miles :)
I have access to a lot of free charging either via Granny lead @ work, 3kw at a local park and ride or Rapid charges when out and about. The free rapids are getting less and less common but still happen and are needed for longer trips, like London and back in a day or such :)

130040
130039
130038
130037
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130044
 

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Interesting Kingpleb, thanks. Although your SoH is still in good territory, the cell voltage variation has been steadily widening. I'm not sure I understand what SoH is based on: capacity, balance, overall voltage...? I wonder what you could do to rectify the voltage variations and whether it would benefit the SoH or car performance anyway.
 

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Interesting Kingpleb, thanks. Although your SoH is still in good territory, the cell voltage variation has been steadily widening. I'm not sure I understand what SoH is based on: capacity, balance, overall voltage...? I wonder what you could do to rectify the voltage variations and whether it would benefit the SoH or car performance anyway.
SoH relates to kWh

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

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Interesting Kingpleb, thanks. Although your SoH is still in good territory, the cell voltage variation has been steadily widening. I'm not sure I understand what SoH is based on: capacity, balance, overall voltage...? I wonder what you could do to rectify the voltage variations and whether it would benefit the SoH or car performance anyway.
The variations depend on SoC.
ideally i should take the screengrabs when the car is showing as 100% full.

I have had 400mv difference once when the battery was into turtle mode.

Leaving the car at a very low SoC, ie 35% or lower, in my eyes, is more damaging than leaving it at a high SoC.
FWIW, mine is rarely sat at anything below 65% as i like to keep enough reserve for any emergency trips, and i tend to get it at more like 90-95% to sit at overnight so its closer to the flat.
I also disconnect from rapids generally at 85-90%, rarely 95%+ as the charge rate is so low id rather move on
 

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Hi, 1st time in forum, my concern is my 2017 nissan leaf 30kwh battery SOH . I bought the car from a nissan dealership with 40000 miles on the clock, I never asked what the SOH was, which I know I should have.
I purchased leaf spy and a OBD2 scanner, my batteries SOH was 77% which I was not expecting, I have now done nearly 41000 miles and the SOH is 72% which is worrying, I have lost 1 capacity bar, and I have now found out my car has not had the software update for the BCM, but still I feel the SOH is dropping too fast, any opinions would be appreciated, many thanks, I've attached leaf spy screen shots
Screenshot_20200324_115031_com.Turbo3.Leaf_Spy_Lite.jpg
Screenshot_20200503_103305_com.Turbo3.Leaf_Spy_Pro.jpg
Screenshot_20200402_105108_com.Turbo3.Leaf_Spy_Pro.jpg
 

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Hi, 1st time in forum, my concern is my 2017 nissan leaf 30kwh battery SOH . I bought the car from a nissan dealership with 40000 miles on the clock, I never asked what the SOH was, which I know I should have.
I purchased leaf spy and a OBD2 scanner, my batteries SOH was 77% which I was not expecting, I have now done nearly 41000 miles and the SOH is 72% which is worrying, I have lost 1 capacity bar, and I have now found out my car has not had the software update for the BCM, but still I feel the SOH is dropping too fast, any opinions would be appreciated, many thanks, I've attached leaf spy screen shots View attachment 130143 View attachment 130145 View attachment 130146
I think the whole point of the BMS update is to sort out an issue where the car thinks that the battery is more degraded than it actually is. If you get that done it should go back up again.
 

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The BMS update just changes the max and min voltage levels so some of us are not convinced that it really resolves the issue properly but it does make the SoH much higher!
 

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The BMS update just changes the max and min voltage levels so some of us are not convinced that it really resolves the issue properly but it does make the SoH much higher!
What was the max voltage when pack is fully charged prior to BMS update? At 91.5%, it was 4.04v prior to update.

After the update, at 89-90% SoC, the cells reported 4.05v

Max voltage (average) at fully charged state is 4.11v per cell post update

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