This is my second season with the following setup:
- WFCO-8955 Power Center
- Victron BlueSolar MPPT 150/35
- 3x Battleborn BB10013 100 Ah 12V LiFePO4 Deep Cycle Battery
- Victron BMV-712 Battery Monitor
- 3x KIT1010 90w Zamp Solar Panels
I have the BMV set exactly according to the battery website (see screenshot):
The issue that I’ve always had is that the displayed SOC decreases much quicker than the actual SOC:
- After connecting to shore power, the batteries will quickly charge and SOC will show 100%, but if the system remains connected to shore power for a day or two, the SOC will drop from 100% to as low as 80%, lower if connected longer.
- When boondocking/drydocking, the SOC will eventually display 0% yet the batteries will continue to put out power for days, running the refrigerator, pump, lights, etc.
This leads me to think of these possible issues:
- Wiring is incorrect. I've had the installer and battleborn/dragonfly check the wiring 3 times. Everything has been verified correct (see screenshots).image008.jpgimage004.jpg
- The battery parameters for the BMV are not correct. This has been checked many times by battleborn/dragonfly.
- The algorithm for SOC is not correct. I can't believe this is true since most people say how accurate this is.
- The batteries have much more capacity than 3x100 aH=300 aH. If the battery bank was substantially higher, then this might explain why the SOC drops to 0% yet I still have power left in the batteries, but it wouldn't explain why the SOC drops even when connect to shore power.
- There's something wrong with the WFCO-8955 charger. There is almost nothing to configure on this except the Li switch (which is correct).
As a possible fix, could I increase the battery capacity? Is this recommended?
Battleborn/Dragonfly says that the system must be completely charged and discharged to 0% 4-5 times before the BMV "learns" the true capacity of the batteries. I haven't seen this documented and so I don't understand how this would work. Is this true?
Anyone have any other ideas? I'd love for this to work, but with the current situation, the SOC is useless.