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Good advice re-the regenerative braking being reduced dramatically above 80% charge.

My understanding is that rapid charging is more effective at cell balancing than 100% charging, but I stand to be corrected.

In terms of your occasional long journeys, speed is a major factor in electricity consumption so just knocking off 5 MPH makes a major difference and may be enough in the marginal need for a second charge. You could also look at increasing tyre pressures and blanking the front grille which make a different if you haven't already done so.
Full regen becomes available around 93% SoC when charged using Type 2. Full regen is available even when I've charged 95% on Rapid.

Balancing is a function of BMS not charging system. AC charging involves conversion to DC before charging. Rapid is DC they meet at a later point.

Above 90% the amps drop enough even on rapid for it to not be faster than AC charging.

- Leaf 30 kWh
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That all makes sense. I'll watch for that figure in future.
 

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Full regen becomes available around 93% SoC when charged using Type 2. Full regen is available even when I've charged 95% on Rapid.
For my 13 Reg 24 kWh Sunderland built Leaf it appears to depend on battery temperature. In cold weather I can find the %SOC has to drop below 80% (below 70% with only 3 bars of battery temperature) before I get full (4 blobs) of regen available.
 

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For my 13 Reg 24 kWh Sunderland built Leaf it appears to depend on battery temperature. In cold weather I can find the %SOC has to drop below 80% (below 70% with only 3 bars of battery temperature) before I get full (4 blobs) of regen available.
My bad. My experience is solely with Leaf 30kwh

- Leaf 30 kWh
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Discussion Starter #25
I would set the timer to charge to 100% at least once or twice a week as this appears to help with cell balancing (but make sure your wife is aware that on the first corner after leaving home with 100% charge, the brakes will feel a bit less effective as there is little or no regen braking when the battery charge % is in the high 90's)
Thanks - i'd come across this behaviour but not understood the cause ! I noted that sometimes the regen was really light/hardly there, but it got better at some point during the trip. I was not sure why, and was wondering if it was some sort of glitch/idiosyncracy/me not turning the car on properly... I drive it in ECO, and think that i rarely use the brakes at all.
 

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I noted that sometimes the regen was really light/hardly there, but it got better at some point during the trip. I was not sure why,
Simply that with a battery at or near 100% charge, there is nowhere for the electrons generated by regen to be put!
 

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On the 30kwh its also Temp and Journey dependent.
I've seen it before that I've had full regen available at 98% with a warm battery when doing a longer run.
Cold days like today even at 85% its not happy to give full regen :(

FYI tesla's do the same with a cold battery regardless of charge state i have found.
 

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On the 30kwh its also Temp and Journey dependent.
I've seen it before that I've had full regen available at 98% with a warm battery when doing a longer run.
Cold days like today even at 85% its not happy to give full regen :(

FYI tesla's do the same with a cold battery regardless of charge state i have found.
Teslas have TMS that manage temperature in a set spot as much as possible unlike what we have with Nissan

- Leaf 30 kWh
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The tesla stuff will only preheat the battery if it knows when you are leaving.
If you're renting to such a vehicle it will never know as you dont have the app and it doesnt learn your habbits.
 

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I was getting a free charge and coffee at my local Nissan dealer (wow; these peeps are friendly and helpful !), and asked whether they'd heard about the Nissan Japan battery replacement option and if it was coming to the UK. They hadn't. But, they did tell me that they could improve SoH and range by replacing 2-3 cells at a cost of £6-700. I'll check this with the service manager during the week (wasn't there on a Saturday); apparently they've done this before (and recently)
Thanks for posting this info, hope you don't mind me asking but who are your local Nissan dealership? I might be interested in having this done. my Leaf is down to 8 bars.
 

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I was getting a free charge and coffee at my local Nissan dealer (wow; these peeps are friendly and helpful !), and asked whether they'd heard about the Nissan Japan battery replacement option and if it was coming to the UK. They hadn't. But, they did tell me that they could improve SoH and range by replacing 2-3 cells at a cost of £6-700. I'll check this with the service manager during the week (wasn't there on a Saturday); apparently they've done this before (and recently).

Has anyone come across this before ? I'm rather doubtful that replacing 2 or 3 cells will return a battery to better health - there are lots of cells, so surely it would be a very limited effect ? (or, is the whole battery performance limited by the weakest cells... if so, then losing the weakest might make a difference assuming that the others are a lot stronger). No, i'm not an electrical engineer :)

This is for a 2012 Leaf, 16k miles, 80% SoH (Leafspy), one bar lost off display, working range about 60 miles. It's in great condition and a better range/battery would be super.

Opinions ?
I'd really like to know about this - I've got a 2011 Leaf with 10bars.
 

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I was getting a free charge and coffee at my local Nissan dealer (wow; these peeps are friendly and helpful !), and asked whether they'd heard about the Nissan Japan battery replacement option and if it was coming to the UK. They hadn't. But, they did tell me that they could improve SoH and range by replacing 2-3 cells at a cost of £6-700. I'll check this with the service manager during the week (wasn't there on a Saturday); apparently they've done this before (and recently).

Has anyone come across this before ? I'm rather doubtful that replacing 2 or 3 cells will return a battery to better health - there are lots of cells, so surely it would be a very limited effect ? (or, is the whole battery performance limited by the weakest cells... if so, then losing the weakest might make a difference assuming that the others are a lot stronger). No, i'm not an electrical engineer :)

This is for a 2012 Leaf, 16k miles, 80% SoH (Leafspy), one bar lost off display, working range about 60 miles. It's in great condition and a better range/battery would be super.

Opinions ?
For starters cells are in pairs, 2 cells per module so either your friendly dealer hasnt got a clue or he is reffering to replacing 2-3 modules.
This can only be undertaken at specific dealerships, I think there is only 2 or 3 in the UK, the one I am familiar with is Lookers Gateshead.
I had 2 modules replaced by them under warranty, but was told the cost would have been about £1500-£2000.

My symptons were as follows:
Low mileage all 12 bars range at 100% 80-90 miles, what I noticed was after about 30miles of driving the range dissapeared at an alarming rate, I would travel 10 miles and lose 20 off the gom and the soc% would plummet.

I did 3 test runs on the same route in both directions incase it was terrain related loss but it was not it was weak cells in the battery.
The BMS calculates what is in the battery using the lowest cell voltage, the BMS was reporting 10% soc on the gom whereas Leafspy was reporting 25% soc.
That 15% capacity was still there but could not be used as the BMS thought that the battery was depleted.

On a 24Kw leaf 15% - 20% is a lot of your range gone !

Since the modules were replaced I now get a reliable real range of 60-70 miles still shows same range on gom 80-90 miles but the discharge is much more linear and predictable than it was before.
 

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As far as I know it's just lookers Gateshead as the other dealership dropped the ball on training so can no longer do it.
Cars either end up there or Sunderland for the work.

On leafspy did your module voltage view show one was way down?
 

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I was certainly told it was only Lookers at Gateshead when my car needed similar attention last year. Have to say they did the job within a couple of days once the car got there - shame about the three wasted weeks when the local dealership didn't get round to examining it ! Incidentally, Lookers are very close to the border between Gateshead & Sunderland so quite likely that when a dealer says "we're sending it to Sunderland" they're just demonstrating their (lack of) product knowledge.
 
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