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Discussion Starter · #1 ·
Hi,
I wonder if it is possible to change the pouch cells in the 24 kWh battery pack of a Nissan LEAF replacing them with more "generous" pouch cells in order to have a new 30 kWh battery pack.
Nissan says you cannot buy a new 30 kWh battery and put it in an old 2013 LEAF with 24 kwh because bla bla bla and bla...(they just want to sell new car).
The cells dimensions of the new 30 kWh battery are the same of the old one...so...what is the problem with a replacing
 

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Design of the battery box is not compatible.
If you are thinking of changing individual modules, that's possible but wouldn't be ease and not sure if it fits in the 24kwhr box.

Sent from my ONEPLUS A3000 using Tapatalk
 

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As stated, you have to take out both batteries and swap all the cells over, reason is the car is matched to the BMS and pack, understand it is quite easy to short something out and moderately difficult to get the interconnections and BMS wires to reach .
others like Cor have done it but the discharge curve for the 30kwhr pack makes it so half your range is after the very low battery warning, irritating but possible to live with
 

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Discussion Starter · #4 ·
you have to take out both batteries
I don't meant to swap cells from a battery pack to another one. I meant to buy NEW pouch cells of the same dimensions of the old one and replace them....
... the car is matched to the BMS and pack
there is a way to hack the (car or BMS) software in order to re-match the car to BMS with the new capacity of battery?

others like Cor have done it ...
I tried to search for some post of Cor speaking about it but I cannot find anything on the forum
 

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I don't meant to swap cells from a battery pack to another one. I meant to buy NEW pouch cells of the same dimensions of the old one and replace them....
If you take a look at the following thread you'll see the pouch cell interconnects are welded together and it would be difficult to replicate this. Indeed in the "Gen 2" battery the pouch cells appear to be glued together.

http://www.diyelectriccar.com/forums/showthread.php?t=163170

IMO it's much easier to work with the new modules and design a battery pack that fits on your 'old' Leaf.

there is a way to hack the (car or BMS) software in order to re-match the car to BMS with the new capacity of battery?
I'm not aware of anyone who has tried this and you'll need access to the Nissan Consult 3 diagnostic hardware/software (warning this is expensive) and be prepared to end up with a disabled Leaf.

I do know that Mike Schooling built a range extended Leaf with two battery packs and two BMS's.

I also experimented with a ~48kWh Leaf battery built by merging two battery packs and using one BMS;

http://www.diyelectriccar.com/forums/showpost.php?p=805713&postcount=7

Wolf has also reverse engineered the Leaf BMS but I don't know if that works in a Leaf;

http://www.diyelectriccar.com/forums/showthread.php?t=169225
 

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I don't meant to swap cells from a battery pack to another one. I meant to buy NEW pouch cells of the same dimensions of the old one and replace them....

there is a way to hack the (car or BMS) software in order to re-match the car to BMS with the new capacity of battery?
No there is not, you have to reuse everything from the existing pack.
The car can learn new capacities to a point but...

If you use "new" cells they need to be electronically the same with the same upper and lower discharge limits as Nissans cells. A few mV different and you could either
1. Damage cells
2. Have a large chunk of your capacity unusable.

The 30kwhr pack from Nissan is the same upper and lower hard limits as the older chemistry but the discharge curve puts the capacity at a lower voltage meaning the car drives 70 miles with the very low battery warning flashing.

This is minor but if you want to use a totally different cell could cause major issues as the car is hard wired to Nissans cell chemistry
 

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If someone were able to provide orthoganal dimensions and images of the GEN1 and Gen2 cases, I would be prepared to design/build a conversion from the “iron” case into a composite case (GF/CF-EP) Laser Scans or an OEM CAD MODEL of the exterior/interiors would be best but not likely available ... :-(
 
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