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Cheapest way to bms 6 16s packs for 60kwh storage li-ion lg chem 180Ah Ev battery

Austenpowers

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I have 60kwh of 3p1s configured to 16s lg chem batterys and want to know the cheapest way to have all the cells monitored
In a large configuration of 6x16s in parallel would ultimately like to monitor all cells but on one bms .

I have put some thort into this and so far I'm planing on using active balancers on the individual 16s packs the 5a version
Along with a voltage switch so the balancers dont flaten the pack and that is as a minimum ..

I have selectronic and fronius ac coupled inverters and it would be good if i could comunicate to the bms with the selectronic inverter but im sure its not done yet...

Is there a way to measure the current on each parallel string with multiple shunts an if one gets a spike the bms will shut down the battery? Or could this be built....

New to the forum Hi every body and thank you
 
The active balancers have a "run" pad that is soldered short circuit. Remove the solder and add any simple switch. Only turn them on when you are running the packs on a charge cycle towards the top. Running them 24/7 has never yielded good results for me. You should only need to run them once a month at most for maybe 24 hours unless your packs get wildly out of balance in which case you need to disassemble your packs and remove the problem groups.

I don't know of any BMS system that allows you to shunt multiple packs and control them separately but it wouldn't surprise me if this was possible with the DIYBMS.

The easiest solution is always the most popular. JBD Smart BMS on every pack. If JBD doesn't communicate with your inverters then JK or Seplos are the other widely accepted quality BMS's. This is one area where you do not want to cheap out if you're going to be cycling these packs as part of a residential system. JBD BMS's are not cheap, they are less than $100 each for a 16S 100A. For inverter comm you will probably be spending just over $100 each

Check out this thread
 
Marko thanks for your responce, I'm concerned that the charge rate wont be limited as the batterys reach 100% as the bms is not talking to my inverter no coms .....
I have the ability to set upper and lower voltages and limit the charge current to one value over all but this is not ideal is it?
My inverter dose support pylontec batterys so im hopping there is a bms available that can emulate the pylontec for my inverter to communicate with it....

Would i really need to concerned about charge current with 60kwh of storage given the total churge current would mostlikley tap out at 100 amps so even if im not able to limit charge current dividing 100 amps into so many cells that at full charge voltage its not a dangerously hi charge rate?.

I would really like to try one of Stewart's DIY BMS but I cant work out the ordering part of the project so ..
Checking the sugested thread out now
Thank you
 
Marko thanks for your responce, I'm concerned that the charge rate wont be limited as the batterys reach 100% as the bms is not talking to my inverter no coms .....
I have the ability to set upper and lower voltages and limit the charge current to one value over all but this is not ideal is it?
My inverter dose support pylontec batterys so im hopping there is a bms available that can emulate the pylontec for my inverter to communicate with it....

Would i really need to concerned about charge current with 60kwh of storage given the total churge current would mostlikley tap out at 100 amps so even if im not able to limit charge current dividing 100 amps into so many cells that at full charge voltage its not a dangerously hi charge rate?.

I would really like to try one of Stewart's DIY BMS but I cant work out the ordering part of the project so ..
Checking the sugested thread out now
Thank you
The cells themselves will refuse to take a high charge rate.

The way CC CV charging works is once the cell has reached a certain point, so long as your charger can be adjusted for a voltage limit and a current limit, the current will begin to fall naturally. The cells are pretty much refusing the current and because they are at the voltage your power supply is limited to the current slowly winds down.

I have never understood the obsession with inverter comms but I'm sure there's aspects I don't understand.

The best way to learn how LiFeP04 behaves is to simply start with some small cylindrical cells like A123 ANR26650M1B's and play around with them. They are remarkably resilient, can handle intense charge and discharge rates, and due to their low capacity it does not take long to charge them up or discharge them so sitting around and physically watching them throughout their cycle does not waste hours of your day.
 
All your BMS requirements sound like a Batrium set up. Multiple modules can be monitored from a central unit, it can speak Pylon tech, but it isn't cheap.

Also, unless your EV pack is an old wasted piece of junk, you shouldn't need active balancing. The car it came from didn't have it, and that was probably 96s
 
I have contacted Batrium as I have the same inverter, unfortunately they told me they were unable to guarantee it would work as they had had other enquires regarding selectronic inverters before. They said previous people had contacted Selectronic and they were not forthcoming with information or help regarding diy batteries and bms.
 
Marko thanks for your responce, I'm concerned that the charge rate wont be limited as the batterys reach 100% as the bms is not talking to my inverter no coms .....
I have the ability to set upper and lower voltages and limit the charge current to one value over all but this is not ideal is it?
My inverter dose support pylontec batterys so im hopping there is a bms available that can emulate the pylontec for my inverter to communicate with it....

Would i really need to concerned about charge current with 60kwh of storage given the total churge current would mostlikley tap out at 100 amps so even if im not able to limit charge current dividing 100 amps into so many cells that at full charge voltage its not a dangerously hi charge rate?.

I would really like to try one of Stewart's DIY BMS but I cant work out the ordering part of the project so ..
Checking the sugested thread out now
Thank you
Did you decide on a bms?
 
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