Valence U27-12xp BMS required?

[Yvan]

I just installed 8 U27-12XP batteries in parallel ( 12v) to replace my lead acid battery bank . Unfortunately the BMS I ordered is slow in arriving.

Can I safely use them a few days without a BMS.
Under voltage protection is provided by my generator that starts automatically at 11.5v.

They are in our pantry, so temps are not a concern.

charging is accomplished by an Epever solar controller, or a Xantrex 458 Freedom inverter charger.

maximum draw is 3000w( peak) average draw is below 1000w.

batteries are interconnected with 2/0 cables, and connected to the bus bars with 4/0 cable.

 

[Dzl]

From what I understand, the main risk of using them without a BMS is that you don't have cell level protection. If the cells are all well matched/balanced, using the batteries without a BMS won't be an issue as long as you stay well away from over or undervoltage. But without the ability to monitor individual cells, there is some risk to using the batteries without a BMS, because you can't monitor the individual cells. The battery pack as a whole could be within the normal voltage range, but if an individual cell is poorly matched, it might go out of the safe voltage range at the high or low end of the spectrum and your inverter/charger and generator would have no idea. If you do use them before the BMS arrives, make sure to stay to set conservative upper and lower voltage limits.