[PAXtss]

Neophyte here - I need some advice.

I just found and ordered the modules from a 2016 Leaf, all (48) 24 double modules which have 8 cells in each (see picture). I am wanting to create a 180V traction pack by putting the modules into two 180 volt packs.I see two ways of doing this:
1- Parallel 4 cells and series the 48 pairs ?- 4P48S ?
The module configuration is not really compatible with this.
It gives 4 cells per BMS unit 48 units


2- Series 48- 2P units and parallel them ? (2P48S)2P?
Two "Wolf" packs if I can steal his naming this. Easy configuration
Gives 2 cells per BMS unit 96 units.
Any advice

 

[PAXtss]

I will try picture again. I may need to find a teenager to show me how.

 

[PAXtss]

These are 2016 - seller called them double modules. I wasn't sure it was correct but searched and found out these are later design - 30 KWH batteries. I bought 24 double module which is 8x24 cells= 192

The issue is that paralleling the cells is tricky- not straight forward like older modules. I see I miss typed in first meassage - said 48 when it was 24- sorry

 

[PAXtss]

If I understand the nomenclature correctly. You are saying build the two 180 packs and then parallel them together. I think this is what Wolf is proposing but with four "Wolf packs" but he has some control circuit boards in there.

This would work with modules as is and would be easiest, I read some where that it was best to do the parallel at lowest level. But that would mean 4 parallel cells for one BMS unit. It would also men taking the modules apart and reordering them- something I prefer not doing.

I am planning on a full fledged BMS

Thanks for your posts Brian- I am always amazed at how much you know and I appreciate your sharing.

I see you posted something while I was working on this post, Does this way above work okay?

 

[PAXtss]

The issue that I see with the double modules is that they are set up to easily connect in series with short connectors. Looking at terminals- One is + tap - and the other one in module is - tap +. Easy to connect in series. To do in parallel will mean either strange connectors jumping over others or disassemble and reassemble so both are + tap - Then two double modules would have a four connection connector at one side and either a double connector or half of another Quad connector on other side. Picture is of my e-truck battery with that set up. It is hard to see connectors. On lower side from right is a double connector, a quad connector, another quad then a double to end stack.

 

[PAXtss]

Thanks for post Kevin,

I thought those were rivets looking (at picture) and I would have to drill them out but I see they appear to be removable and reusable.

Back to my original question about whether to do all parallel connections at lowest level which would be 4 cells or to parallel the half batteries like Wolf is doing. There are pro and con both ways and you (possibly) eliminate one for the lowest level paralleling.

I am inclined to do the Wolf pack as it means every two cells have a BMS connection versa a BMS for 4 calls. But I don't know all the ins and outs of this.

Thanks for help- You guys are great - helping and putting up with less technical folks.

 

[PAXtss]

Great- parallel half packs (Wolf style) it is. I think I will just use off the shelf BMS with the ability to balance and keep an eye on everything. I did not get anything but the modules and a few power cables. I am a plug and install person and I do not have the technical skills to work out the Leaf setup. Computers were developed after I was born. Engineering school still had pencil type mechanical drawing courses. Punch card computers, too.

Kevin- thanks for link to the split screen van. I have been following for a while but did not remember about the battery part.

 

[PAXtss]

I partially disassembled one of the Gen. 3 modules to see if it would be possible to reconfigure the double module for easy paralleling at the lowest level. The modules are double modules and put together to connect in series and I wanted to see what it would entail to separate the sub modules and turn one end to end so the terminals are both positive at one end and neg. at other and can be connected in parallel easily.
In previous post is a link to Kevin's dismantling a Gen2.
The Gen 3 is similar with the same compression type caps that are really easy to remove- a sharp chisel easily lifted these caps. I then lifted off the aluminum cover- it was glued but not very tightly and came up easily. The 8 cells are all stacked together and are glued together.
I quit at this point as I think I could separate the 4th and 5th cells but having to do 24 of them gave me pause. This is an expensive battery and I did not want to take a chance on damaging any part.
Pictures :
caps removed
close look at cells

 

[PAXtss]

After spending hours and bugging you guys I have come up with a way to parallel the modules. Reminder- this is the 2016 Leaf gen 3 battery which has two modules permanently attached together such that there is a positive and a negative terminals are each end of module. This is easy to connect in series but harder to connect in parallel. So I came up with some special busbars to connect the modules. Actually John at Thunderstruck clued me in on this.
Let me know if I screwed this up.