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Want to confirm my understanding / be corrected. Looking at EV west website for LG Chem batteries "A common configuration of the LG Chem batteries is 2p6s" When they say batteries they mean the LG Chem Module made up of the smaller cells.

2p6s is 12 modules, 6 in series parallel to another 6 in series, correct? The 6 in series gives you 15.6kWh (2.6 X6) + the other 15.6 for 31.2kWh. and 364.8V (60.8V X 6 in each "pack"), correct?

So I understand series is wired + - + -... and parallel is + to +. - to -. but I get confused when you need to put the modules in parallel (idk, but I cant wrap my head around it) Is the image accurate for attaching the models in parallel? I have my 6 each in series, then parallel to the other 6 in series? Then going out to connect to the rest of the system?

Again I am looking to confirm a basic understanding. If I were to add another model I would then do the same, 6 in series parallel the "second pack"?
 

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2p6s is 12 modules, 6 in series parallel to another 6 in series, correct? The 6 in series gives you 15.6kWh (2.6 X6) + the other 15.6 for 31.2kWh. and 364.8V (60.8V X 6 in each "pack"), correct?
The EV West listing says 2.6 kWh per module, so it's 12 x 2.6 = 31.2 kWh in total, regardless of how they are arranged.

Add charge capacity (in amp-hours) for parallel connections, and voltage for series connections... and just add up the energy (regardless of series or parallel configuration).
 

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2p6s is 12 modules, 6 in series parallel to another 6 in series, correct?
...
Is the image accurate for attaching the models in parallel? I have my 6 each in series, then parallel to the other 6 in series?
Yes, that's what 2p6s means, and the description is a valid configuration for six times the voltage of a single module and twice the charge capacity of a single module (which would be 364 V nominal, and about 85 Ah, given that the modules are 60.8 V and about 42.8 Ah per module).

In that diagram, only the upper right and lower right cells are paralleled.
In that diagram one set of 6 modules in series is connected in opposition to the other set of 6 modules in series, so the result is useless - no voltage, no capacity. Sorry, I don't have the time at the moment to draw the correction.
 

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Discussion Starter #5
Well at least I was right in my understanding. Is the attached more accurate? Since the packs are likely to be separated in location anyway, I would connect my positive wires, then out/in. Ditto for the negative?
 

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Well at least I was right in my understanding. Is the attached more accurate? Since the packs are likely to be separated in location anyway, I would connect my positive wires, then out/in. Ditto for the negative?
Close but no cigar. Take those two positive links off the left end and put them on the right end of the pack.
Think of current as a hose filled with water flowing through each battery. Right now you've got no outlet on the right side of the pack.
 

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Close but no cigar. Take those two positive links off the left end and put them on the right end of the pack.
Think of current as a hose filled with water flowing through each battery. Right now you've got no outlet on the right side of the pack.

LOL at myself.... thank you! Next time I will wait for more coffee to be in my system, that was dumb. Posting (what is hopefully) correct for others to reference.
 

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The usual convention (which isn't obvious) is that you read the configuration string from right to left, representing the lowest level to the highest level (like a numeric value... least significant to the right). So "2p6s" means that six cells (or modules in this case) are connected into series strings, then the two strings are paralleled together.
This is 2p6s
note: 2p = 2 parallel, 6s = 6 series
the other drawing that has the most bizarre connections is / was almost 2 strings of 6s
The drawing above shows the opposite order of connection: paralleled pairs of cells, then the cells connected in series: that's 6s2p (and the more typical EV configuration.


This is 2 strings of 6s paralleled together, note that every string needs it's own Fuse / breaker.
Now that's 2p6s, which is indeed 2 strings of 6s paralleled together. I believe that this is what EV West is suggesting for the LG modules (which I assume are from a Chrysler Pacifica plug-in hybrid).
 

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Discussion Starter #18
Now that's 2p6s, which is indeed 2 strings of 6s paralleled together. I believe that this is what EV West is suggesting for the LG modules (which I assume are from a Chrysler Pacifica plug-in hybrid).
Do you think they are used modules? I thought they were new, as EV West normally notes when parts (mainly Tesla) are from salvaged or previously used.
 

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Do you think they are used modules? I thought they were new, as EV West normally notes when parts (mainly Tesla) are from salvaged or previously used.
They might be new - I just meant that they are the same modules which are used in the Pacifica.

I don't know where they get these things... it looks like they are not available from Chrysler dealers as replacement parts - only the complete battery assembly (with 8 modules) is available. Maybe they got a good bulk deal on complete batteries from a dealer, and are breaking them down into modules for retail sale? The complete battery retails for under $9K.
 
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