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Which is why it hasn't been sourced by Muxsan who supply and fit for €8790. If you want it you should be paying £6.5 as Muxsan only charge €1500 to fit a supplied battery.
 

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Which is why it hasn't been sourced by Muxsan who supply and fit for €8790. If you want it you should be paying £6.5 as Muxsan only charge €1500 to fit a supplied battery.
Possibly true.

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Can one of you clever guys explain to me is a weak cell damaged/ always need replacing or can a weak cell be manually balanced and used again, or is this only applicable to cells that have been replaced and not balanced before figment ?
Sorry if this sounds like a stupid question!
 

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It's a weak cell, the symptoms are back and white.

Do a leafspy screen capture when it is close to 0% SOC, and you'll confirm this.

Ask Nissan/independents for the cost to replace. Time to break out the piggy bank.
 

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Can one of you clever guys explain to me is a weak cell damaged/ always need replacing or can a weak cell be manually balanced and used again, or is this only applicable to cells that have been replaced and not balanced before figment ?
Sorry if this sounds like a stupid question!
It is one cell which can no longer hold the same amount of charge as the rest.

As a consequence, because they are in serial, the whole pack can only charge and discharge according to that one cell (else that cell will go too high or too low).

If all your cells are 30Ah cells giving what should be a 60Ah pack (they are paired up), but one pair has a defective cell so it's only 30Ah, then your pack size becomes effectively 30Ah. You can charge it up the same as the others, but it'll be flat while the others are still only 50% discharged.

It might not be as bad as '50%' and a complete cell failure, but the explanation is for illustration.

Piggy bank time.
 

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It is one cell which can no longer hold the same amount of charge as the rest.

As a consequence, because they are in serial, the whole pack can only charge and discharge according to that one cell (else that cell will go too high or too low).

If all your cells are 30Ah cells giving what should be a 60Ah pack (they are paired up), but one pair has a defective cell so it's only 30Ah, then your pack size becomes effectively 30Ah. You can charge it up the same as the others, but it'll be flat while the others are still only 50% discharged.

It might not be as bad as '50%' and a complete cell failure, but the explanation is for illustration.

Piggy bank time.
Thanks
 

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Can one of you clever guys explain to me is a weak cell damaged/ always need replacing or can a weak cell be manually balanced and used again, or is this only applicable to cells that have been replaced and not balanced before figment ?
Sorry if this sounds like a stupid question!
I don't think it's a stupid question as the symptoms seem the same. :unsure: :eek:
Something told Emile that the cell was recoverable rather than needing changing. That appears to be that when the pack was discharged it showed the same voltage as the others and the difference only occurred when the pack was fully charged. Certainly that implies that the cell has remaining capacity (which I would have expected even damaged cells to have) but doesn't explain why it wouldn't charge to the same voltage as the others.

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I also don't understand why topping it up once will mean that it doesn't will not drop again. :unsure: Maybe it will but just over another 50,000 km?
 

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Welcome to the Wonderful New World of EVs, and a new set of problems for motorists to wrestle with. Gone are 'cambelts' and 'catalysts' and 'head gaskets', and introduce a new lexicon; 'bad cells', 'bad earth', 'motor bearings' ....
It is great so many of you know what you are talking about!
You don’t need a mechanic any more just a degree in electronics!
still nice to try a pick up a bit of how my leaf works.
 

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Welcome to the Wonderful New World of EVs, and a new set of problems for motorists to wrestle with. Gone are 'cambelts' and 'catalysts' and 'head gaskets', and introduce a new lexicon; 'bad cells', 'bad earth', 'motor bearings' ....
And coolant change at service time at £400+
Not for a Leaf of course as there ain’t any.
 

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If i'm not mistaken, the factory BMS cant "charge" a low cell. All it can do is try to drain the high cells down to match the low ones, and then you can recharge the whole pack in series as normal. The BMS' ability to drain cells is also tiny, tens of ma's, so i really doubt a few "forced" charge cycles is going to fix it.
Manual balance might work, but realistically, the cell has got out of balance probably because it has less capacity than the others, which means when you've gone to the effort of hauling the pack out of the car, wouldnt you be better off just replacing the cell?!
 

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If i'm not mistaken, the factory BMS cant "charge" a low cell. All it can do is try to drain the high cells down to match the low ones, and then you can recharge the whole pack in series as normal. The BMS' ability to drain cells is also tiny, tens of ma's, so i really doubt a few "forced" charge cycles is going to fix it.
Manual balance might work, but realistically, the cell has got out of balance probably because it has less capacity than the others, which means when you've gone to the effort of hauling the pack out of the car, wouldnt you be better off just replacing the cell?!
This post brings me to a question as I haven’t seen the answer.

Once out of warranty, what options are there for inside the battery pack spares? Do Nissan offer them? Is it limited to other used breaker stock? Is there a chargeable ‘back to Sunderland’ offering?
 

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I suspect like most things with used vehicles, once they're out of warranty, the main dealer becomes economically unviable for a lot of repairs once a car is perhaps ~5 years old. If the engine fails in your 2014 Astra, i suspect people generally wouldnt go and buy a new one from Vauxhall (unless you had some sort of warranty to claim against perhaps), you'd instead goto the breakers and source a good used one, or have it repaired by an independent shop if possible.

The combination of high labour costs, and high parts prices just means its a no-go.
 

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I suspect like most things with used vehicles, once they're out of warranty, the main dealer becomes economically unviable for a lot of repairs once a car is perhaps ~5 years old. If the engine fails in your 2014 Astra, i suspect people generally wouldnt go and buy a new one from Vauxhall (unless you had some sort of warranty to claim against perhaps), you'd instead goto the breakers and source a good used one, or have it repaired by an independent shop if possible.

The combination of high labour costs, and high parts prices just means its a no-go.
My point is (re Donald’s ‘pair of cells’ post) the pair of cells is a haporth of tar type issue if you can’t get them.

Is anyone breaking packs and offering guts (ignoring the logistics of getting the pack out and opened to make replacements)?
 

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My point is (re Donald’s ‘pair of cells’ post) the pair of cells is a haporth of tar type issue if you can’t get them.

Is anyone breaking packs and offering guts (ignoring the logistics of getting the pack out and opened to make replacements)?
there certainly seems to be folks around who are breaking packs down and offering cells. I'm sure the specialists that actually do the work will have supplies of used packs. there are even folk selling cells on ebay, thought thats likely a crapshoot as to what your getting!
I've had half an eye on ebay for whole packs for a while, and acutally supplies of them seem to have dried up as time has gone on, rather than becoming more ubiquitous as i'd have expected. I presume this means they're being bought up by specialists who have arrangements with the scrap yards, and snap them up before they hit general sale. The ones that do appear are rediculously overpriced (someone on there currently asking nearly 6 grand for a used 2011 pack... you can buy a whole car for that ffs)
 

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There can be issues with certain cells being lower capacity than the others as they age, you would usually see this as the cell going higher voltage than the others on a rapid charge and lower than the others when at a low state of charge (not charging). It can also be the case that if you rarely charge to full then the cells get out of balance and the car cannot get them into balance as it can only balance a certain amount, so the "low" cell is still a similar capacity to the rest of the pack, just needs charging.

I would check the cell voltage on a rapid charge - if it goes high then its gone high internal resistance and low capacity and needs replacing. If it stays at a similar voltage relative to the other cells (i.e. a bit below the rest) then crack the lid and charge it.

Cheers.
 
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