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Hey Guys,

I was wondering if anyone had reconfigured these modules to be a bit more BMS friendly at anything > 30kWh? I am looking at creating a 50kWh pack with a nominal voltage of 300v, which is 5S4P at the module level.

As I understand it to achieve my target kWh and voltage this would mean I could not use a Zeva bms (or any distributed bms that I'm currently aware of) as that has a max cell count of 192 and in this configuration I would be running 320 cells.

I believe I could do it with an orion BMS configured in a 1x master 3x slave config which has some cost implications. I'm not aware of anyone on this forum who is running slave Orion BMS systems? If there is anyone out there running a similar slave setup for parallel packs I would love to hear about how the process went?

Another alternative would be to reconfigure the LG Chem modules to be 4S 4P and utilise the Orion to monitor the series connected cells, I understand this is possible but is it recommended? Has anyone done it and if so do they have any advice?

Have I missed anything / any recommendations are greatly appreciated! I will be using a Tesla Rear Drive Unit hence the requirement for the voltage + a decent discharge rate.
 

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I don't know the physical details of the pack, but

many setups do not attempt to monitor / protect at the individual cell level.

If at the "bottom level", you can put cells into parallel groups, each group acts as a single cell for monitoring & control purposes.

Of course you need to pay attention to the performance of the groups, as a cell failure will usually be "masked" at resting voltage

its lower group Ah **capacity** the only sign of trouble

the whole pack being limited by its weakest link.
 

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These are pouch cells, with terminations to tabs presumably much like a Volt pack. Some people have reconfigured those (and that might be something to search for in the forum), but it's not trivial.

I don't know the physical details of the pack, but many setups do not attempt to monitor / protect at the individual cell level.

If at the "bottom level", you can put cells into parallel groups, each group acts as a single cell for monitoring & control purposes...
That's exactly what Squashbox is proposing.
 
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