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With multiple SCC, I would think four could drop off at lower voltage and last one would charge to full slowly.

Of course, loads could be taking current too. If last one was Victron with battery shunt and Cerbo, it could be told to limit battery current to a couple amps. (Judicious ordering of connections of various SCC and shunt would allow lower voltage SCC to deliver full current to battery, and just the Victron would feed whatever to loads plus limited to battery.)

Not as good as closed loop, but might work decently.
 
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With multiple SCC, I would think four could drop off at lower voltage and last one would charge to full slowly.

Of course, loads could be taking current too. If last one was Victron with battery shunt and Cerbo, it could be told to limit battery current to a couple amps. (Judicious ordering of connections of various SCC and shunt would allow lower voltage SCC to deliver full current to battery, and just the Victron would feed whatever to loads plus limited to battery.)

Not as good as closed loop, but might work decently.
Okay, sorry that made no sense to me whatsoever! Complete beginner here.
 
Okay, sorry that made no sense to me whatsoever! Complete beginner here.

Some BMS used with lithium battery support communication with inverter/charge controller.
That lets BMS request reduced current, so the rebalancing of cells can be performed. Without that, voltage rises too high and either BMS disconnects (shutting down system) or charge controller drops to float voltage.

Using other SCC that don't communicate with the system (open loop), you probably have that issue of not giving much time for BMS to rebalance.

What I'm thinking is one SCC configured for low current could keep operating during cell rebalancing. The other SCC could be configured for lower voltage and would drop off. Some SCC could be programmed to limit battery current to say 2A, while supplying up to 40A for inverters. That could improve behavior.

For a system to be simple and automatic for you, ideally get a battery and inverter/PV charger (hybrid) that talk to each other.
There may be some systems that work OK without that communication. I think it will depend on how well lithium cells remain balanced. It could be premium priced products have well matched cells, and inexpensive ones get imbalanced sooner. But maybe all will with age.

There's a bunch of firmware/software to make these things work well. And prices are all over the map.

Thank you.

Compatible to make a system without communication.
Some people have reported batteries disconnecting as system got older.
This is not a mature industry, so expect growing pains (translate: your system stops working, and you can't find anyone who knows how to fix it.)

Even the premium names and prices don't ensure everything is fine. There have been recalls of UL listed battery systems.
"Caveat Emptor"
 
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