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Hi everyone,

Can anyone explain the meaning of the "6S 86P" battery module in a tesla? I understand that it means 6 in series and 86 in parallel connections. From what I know, a module consists of maybe 444 individual cells. How does that add up?

Tried google and still can't grasp the idea of it.
 

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Nissan Leaf Accenta 30kWh, 3.3kW, 2017
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It means that you connect 86 cells (an AA "battery" would be considered a cell in this case) in parallel, which means all the positive ends are connected together and all the negative ends are connected together. You then get the same voltage as a single cell (average around 3.7V), but a lot more capacity. If a single cell was 3Ah (i.e. provides 3A for an hour before running out), having 86 in parallel would give you 3 x 86 = 258Ah.

The series part is then connecting each of these "supercells" end-to-end effectively; with the positive connected to the negative of the adjacent supercell. The equivalent is when you put multiple AA cells into a device like a remote, where you either put them in a line or nose-to-tail. This builds up the voltage, so a 6S module will have an average voltage of 6 x 3.7 = 22.2V.

Why you would do it like this is down to various considerations. The base one would be the maximum voltage of the whole battery, and I think the "class" changes once over 400V, which is why a lot keep to just below this. You then would look at your packaging and work out how much you can squeeze in to see what the capacity/range will be. There are also H+S issues like handling voltages over 50V DC, which is why you normaly keep your modules to below 12S (maybe higher if you don't deal with charged modules). This is the method we normally use when making batteries, with an "arming" stage towards the end of the build so we don't have to wear special gloves, which reduces are dexterity.
 

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Can anyone explain the meaning of the "6S 86P" battery module in a tesla? I understand that it means 6 in series and 86 in parallel connections. From what I know, a module consists of maybe 444 individual cells. How does that add up?
That example doesn't add up - 6S 86P is 516 cells and are the modules in the P100D, 444 cells was a previous architecture of 6S 74P used in the lower capacity 85 Tesla model S.
So for all 16 modules you end up with 8256 cells - that is one heck of a lot of welded connections!
Those of us mere LEAF owners are just 2S 96P for the whole car - 192 pouches - much simpler but harder to cool and maintain mechanical integrity for.
 

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the new Tesla LFP packs have many fewer cells, many less welds. the 4680 packs will also have many less cells and welds when they come online.
 
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Those of us mere LEAF owners are just 2S 96P for the whole car - 192 pouches - much simpler but harder to cool and maintain mechanical integrity for.
Other way around; 96S 2P. Or we would only have an 8V battery! Pouch cells can be cooled more easily as they have an easier surface area to work with (a rectangle, rather than weaving through a load of cylindrical cells), just that Nissan decided it wasn't worth the effort I guess. Mechanically, both have pros and cons. There are far more connections with cylindrical, and one failing can reduce the capacity of the battery. In Tesla's example, having such a large amount in parallel helps as you would only lose 1/86th of the capacity.
 
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