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It's very good news indeed. I guess it's not REALLY that important in the grand scheme of things (surely you could source a battery replacement anyway once out of warranty) but it wraps it up and keeps it simple, which has great value in itself.
 

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surely you could source a battery replacement anyway once out of warranty
Really? Perhaps someone can tell me where I could get a battery replacement from if not from Nissan? There are no swap-out replacement packs available AFAIK.
 

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Really? Perhaps someone can tell me where I could get a battery replacement from if not from Nissan? There are no swap-out replacement packs available AFAIK.
If the demand is/was there I'm sure a supplier would come forward, it's what happens in the car market (and just about any other market). Not sure if you can now, because I doubt the demand exists at present, but if and when it did or does I'm certain suppliers will want to make money from that.

Now this worry is gone, because Nissan will do it first.

Longer term this may in fact make it easier and quicker for the aftermarket to react if they feel it's profitable, because it sets an OEM baseline.
 

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What this does do I think is make used LEAFs more appealing, at least emotionally if not really in practical terms.

I mean, if I was buying a used car and the reassurance was "hey, you can make one part like new for £5k" I'd want to feel the car was somewhere near £5k cheaper to counter that. It's not so simple when you think it through, but it's emotions that matter with car purchases most of the time. If the conversation was more like "what about the battery?" and the reply is "it's warrantied, but later on you can get a new one from Nissan for a good price, but I doubt you'll get there to be honest" it'd be good.

I don't think the average person buying now, with nice long battery warranties, will really be affected by this for a very long time, and by that time the batteries may have changed a fair bit all over again.

For the most part I think this services a vocal minority who are very important as early adopters and innovators, more than the mass market.

No doubt it's very good news though, shows commitment from Nissan and the recycle/trade-in aspect means it's win/win.
 

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I think what is does do is silence a very vocal minority of petrol heads who keep trotting out the line that the batteries only last 3 years and then cost £10k/£15k to replace effectively making a second hand Leaf worthless.

I've spent £3k having a diesel engine rebuilt before, so a battery pack at that price with a big warranty from the cars manufacturer, along with the recycling of the old one is just perfect. Good work Nissan :)
 

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It will be more than that in the UK, minimum of £4,125(converted to $ and then %20 VAT) + installation (I would guess a whole day of labour, £300?)

So basically, it will be £5k.

Still, someone can keep that figure in mind as their Leaf slowly loses capacity, and if they have a 10 year old car with nothing else wrong with it then it might be worth it. Certainly if the price stays the same and it's always for the -newer- battery it could be a good way for Nissan to get continued revenue from older cars.
 

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I thought the whole point of the modular design was that it never needed the whole pack to be replaced, you just replaced the cells that were the issue, so what circumstances would require a full pack replacement ?
 

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All the cells are used in parallel, so the "only the cells which are worn" thing is a bit of a misconception. If one particular cell is faulty or damaged, sure, that can be replaced, but gradual wear will affect all cells equally.
 

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All the cells are used in parallel, so the "only the cells which are worn" thing is a bit of a misconception. If one particular cell is faulty or damaged, sure, that can be replaced, but gradual wear will affect all cells equally.
Not true...

The 24 kWh Leaf battery pack consists of 48 modules and each module contains four cells, a total of 192 cells.

Within each module of 4 cells they are arranged in pairs in series and the two pairs are then in parallel.

All 48 modules are then in series.

They could not all be in parallel because the nominal voltage of the entire battery is 360V. That is achieved as follows:

Each cell... 3.75V
2 x in series... 2 x 3.75V = 7.5V
2 pairs in parallel... 7.5V module nominal voltage

All modules in series... 48 x 7.5V = 360V

Any module can be replaced in-situ so if there is a module that is down then it can be replaced on its own without affecting the other modules.

More info here from the manufacturer: http://www.eco-aesc-lb.com/en/product/liion_ev/
 

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Right, when I put a load of 200 amps on the pack I am taking 200amps from each module. I don't take 50 amps from module one, 50 amps from module 2,3 and 4, and nothing from modules 5-48. They all give and receive power together, at the same time. There's no fancy switching of anything to use some modules more than others.

The point I am making is they are all given equal use, and equal wear. So for defects, damage and faults, replacing one module may be appropriate. But if you have a pack with 60% of it's original capacity and want to get it to 100%, you will need to replace all the modules (realistically you replace the pack as one piece) not just a handful of modules.
 

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Right, when I put a load of 200 amps on the pack I am taking 200amps from each module. I don't take 50 amps from module one, 50 amps from module 2,3 and 4, and nothing from modules 5-48. They all give and receive power together, at the same time. There's no fancy switching of anything to use some modules more than others.

The point I am making is they are all given equal use, and equal wear. So for defects, damage and faults, replacing one module may be appropriate. But if you have a pack with 60% of it's original capacity and want to get it to 100%, you will need to replace all the modules (realistically you replace the pack as one piece) not just a handful of modules.
Wrong again! Sorry. :)

They will all be at different voltages depending on their condition and state of charge. So when you put them under load they will discharge differently. It isn't the simple "one size fits all" that you describe.

In fact, it is even more complex than that because the Battery Management System (BMS) controls a shunt for each cell (or cell pair?) and that shunt can be controlled and cut in and out depending on the balance of the load between the cells and in that way the BMS aims to create that balance you describe.

The shunts also operate when charging to balance the cells dynamically during the charge and then again in a balancing "cycle" at the end of the charge.

If some of the modules are showing as down on capacity then it is perfectly possible to replace those modules only and get a significant increase in capacity/range but yes, you are correct... if you want a battery with new range you will need to replace them all :)
 

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Wrong again! Sorry. :)

They will all be at different voltages depending on their condition and state of charge. So when you put them under load they will discharge differently. It isn't the simple "one size fits all" that you describe.
It is for the context of this discussion. Some people believe that the car places significantly more demand on some modules than others, that you start with 48 fully charged modules, and as you drive module 48 gets emptied so you start using module 47 then 46 etc. That leads them to believe that module 48 gets worn out fastest so you can just replace it and hey presto you're back to 100%. I am just making the point that that's not how it works.
 

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I have never heard anyone make that assumption but in case they do then that point is well made... thanks :)
 

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If we say 100,000 miles to get to a point where the battery range is not acceptable.

At 5 grand that works out at 5 p a mile.

Add in the cost of charging at 2p a mile rounded up.

That gives a total fuel cost of 7 p a mile.

Roughly half the cost of running an economical ice car.

With the potential to keep running the vehicle much longer.

Wonder how long the vehicle could run for before the motor, bms etc need replacing.
 

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To refettle an ordinary Prius battery (not the PiP) New modules where necessary, balancing etc. is £500-£600 inclusive of all costs and a 12 month guarantee to get things into perspective. A fair number of third party garages doing it too as the demand increases for 12-13 year old cars.
 
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