Nissan leaf BMS With CATL 180ah Modules

[maiks]

I'm building a 62 kWh battery pack using CATL modules, each with a capacity of 180 Ah, a voltage of 14.8V, a weight of 11.9 kg, and configured in a 4S arrangement. I'm currently using a Nissan Leaf BMS, which I believe is rated for around 40 kWh; it has three temperature sensors, one black high-voltage header, and one grey low-voltage header. To read data from the BMS, I'm using Leaf Spy along with a Bluetooth OBD2 scanner. My plan is to separate the battery pack into two boxes: one with 8 modules in the front and another with 16 modules in the rear.

What have so far achieved
I've successfully connected the BMS to the OBD2 scanner, but Leaf Spy isn’t displaying any data. I suspect this is because l have not yet connected modules

As a newbie, I’ve done most of my research online, and I would greatly appreciate any guidance, suggestions, or advice on how to proceed. Thank you!

[johu]

Maybe this helps: https://openinverter.org/wiki/Nissan_Leaf_BMS

You will find the 40 kWh BMS is confused with higher capacity cells, i.e. the state of charge will be off.

Maybe this is interesting for you: https://openinverter.org/wiki/16-cell_BMS

[maiks]

Thank you Johu

l want to start with Nissan leaf bms then later may be l will upgrade to 16-cell_BMS

[maiks]

I've successfully connected the BMS, and it shows all 96 cells, with the three temperature sensors working. However, I noticed that in all the YouTube videos I've watched, Leaf Spy displays red and blue lines for the cells, but mine only shows blue. Is the BMS functioning correctly, or am I missing something?

Also, for the BMS gray connector, I used the ground, ignition, charge, and sensor wires, but I didn’t connect the two interlock wires. What exactly do the interlock wires do, and will their absence affect the BMS operation?

[jrbe]

My understanding is the red lines in leafspy are cells that are balancing. These typically flash / jump from screen refresh to screen refresh. I usually see it when charging.

If you're never seeing it, I wonder if your battery is in a storage mode..

[maiks]

My understanding is the red lines in leafspy are cells that are balancing. These typically flash / jump from screen refresh to screen refresh. I usually see it when charging.

If you're never seeing it, I wonder if your battery is in a storage mode..

yes these blue lines also flash / jump from screen refresh to screen refresh and even the mV keeps on changing

[ianlighting]

When Chinese companies sell their CATL modules to Leaf owners, they include a CANbridge to make the different capacity work with what the car is expecting. Some also reprogram the BMS. If this isn’t something you’ve looked into, it is worth exploring.

Also today, Dala released a new video related to this which you should watch. It will lead you on to another forum where some R+D is ongoing.