Lifepower4 - One battery (out of two) went to 0% suddenly

[jarred125]

My setup:

Sol-Ark 15k paired with 8.9kW bifacial panels + grid tied (no grid sell)

It is quite likely that this is due to my own stupidity and not managing the SoC well enough, I have had days where the batteries did not charge fully for various reasons (not enough production, etc). Yesterday we had a good Sun(day), cool temps and lots of sun so I charged our EV as well as the two batteries in my bank (I have two more on the way). I noticed at one point that the SoC on the Sol-Ark LCD read 100% but had a warning on the battery system. I checked the Lifepower4 hub and saw an alarm as well as both of my batteries in an alarm state. The first battery was showing Short Circuit and the second was at 0%.

Looking at my graphs with the PV Pro app (ugh, not great but I also have it interfaced via the RS485 port on the Sol-Ark to home assistant), I saw a significant drop in voltage suddenly as if one pack just stopped responding. I turned off the breaker to the 1 battery and charged the second that was at 0% to around 40% then powered on the second battery again, the first one stopped giving the short circuit (and lovely buzzing sound) that it had been.

My issue is, I have no clue how this would just drop to 0% like this. It feels like the BMS and hub are not really communicating with the Sol-Ark though it indicates it can see the voltage, SoC, current, temp and actually read the error codes from the BMS.

I need to get my laptop up so I can use BMS Test to read everything, so I will post those screenshots shortly.

Thanks for any light you can shed on this.

 

[jarred125]

Went out with BMS Test and found that the second battery, the one that dropped to 0% had some issues at some time. Cell over voltage protection kicked in (I think... maybe not reading this properly). Anyways, here are the screenshots. After a reset of the BMS the error states cleared (for now).

Multibatt-1 is the first in series, multibatt-2 is second, then batt-2-single-1 is just the single view.

 

[jarred125]

Spoke with SignatureSolar support, the CMOS being off is due to one of the cells being over voltage. I am discharging the batteries right now to around 50% to make sure that clears.

Support indicated setting the float V to 54, but this setting is overridden by on the inverter due to the closed loop comms, it sets to 56.2 which is the max voltage on the communication hub.