After going through 4 different BMS's I tossed them all.
I now only use an active balancer. The balancer is working flawlessly.
I only charge to 53.1 and discharge to 46.0.
The Active balancer is finicky and doesn't really like to stay connected to blue tooth. As long as it balances the bottom and top cells, I don't care!
Today I redid one wire harness.
The Active Balancer I use on eBay.
I charge from AC at only 2.5 amps per pack.
I charge from DC at whatever the sun will give it. I have it set to 20 amps max per pack, but I have never seen more than 8 amps per pack.
I can discharge at 20 amps per pack on occasion, but normally just 4 to 6 amps per pack.
End of cycle daily use (1 of 4):
Before the cycle use actually being solar charged:
Usually, at this time of day the pack is fully charged, however, I charged my Chevy Bolt EV this morning.
The "setup":
I have the massive thread for the "plug-n-play" connector.
https://diysolarforum.com/threads/byd-bms.3034/
The connector part of the thread is perfect. Don't bother with the BMS, just go active balancer.
One of the only "minor" issues that I now have with these BYD's is that they have a lot of internal resistance(IR), see on the screenshots above. This active balance cannot balance if there is too much IR. Even though I have 2 amp active balancers, I can only have them set to maybe 1.3 amp. On occasion, even that is too much. So to keep from having to mess with them I set them all to 1 amp and that is working great.
After I switched off today's cycle, and returned to the grid for the night, this is what the packs show:
I did not check the meter I installed before for how many kWh of use this was, but this is 6 hours of 100% off-grid use. With 8 packs, I can get about 24 hours of use with no sun to recharge. If I have a good solar day to recharge, there really is no limit to how much I can be off-grid. But for now in early December, the sun is low and my off-grid panels are on a practically flat roof, maybe 5° slope.