LiFePO4 soc 100% but volt 13.7

Hi, I have two 200 Ah in parallel and my Bluetooth BMS tells me I have 100% Soc on both batteries despite voltage of 13.6. The solar panel still charges the battery and my charger is set to turn off charging at 14.1 volt.... can I just disregard the soc and rely on the voltage to determine the “real” soc? Any help appreciated!
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Based on the settings of 14.1V for charging that seems reasonable for a XP 4S bank, as there is very little added capacity above this region, so perhaps the BMS is recording 13.6 V as a 100% SOC as part of a conservative indication. What is the application of the battery, off grid, standby or ??? Lots of guessing on my part but essentially 13.6 V is in the 90% + safe region preferred for off grid use, what is the low voltage disconnect? That would be the next question, hopefully it's greater than 12V.
Additionally were the cells ballanced before application and if so we're they top or bottom ballanced? If applicable of course.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Having Li batteries at a 0% state of charge, is going to be a problem. That's the initiation for a battery fire at some point later on.
At least, that's what I understand from the interwebs.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
From the photos, it looks like the turbine tower is too short (lots of buildings and trees as tall, or taller than the turbine).
Also, what is the wattage of your solar panel... Assuming ~250 Watts:
- 250 Watts * 0.77 panel+controller deratings * 1/14.0 volts charging = 13.75 Amps peak charging current (best case, cool/clear days, solar noon)
Assuming 250 Watt panel/array, fixed tilt, facing south, Stockholm:Stockholm
Measured in kWh/m2/day onto a solar panel set at a 46° angle:Average Solar Insolation figures
(Optimal summer settings)
- 400 AH / 13.75 Amps charging (est.)= ~32 hours of sun
- 32 hours of sun / 5.57 Hours of sun per day (June ave) = 5.75 Days of average sun (June) to fully charge
-BillYes the built in BMS makes the battery intrinsically safe (safe in and of itself, by design ) One thing to avoid is frequent deep discharge, if you're regularly nearing 0% indicated SOC, it would be prudent to limit such events to extend cycle life expectancy, in other words increase the charging capacity to compensate and or increase battery capacity, see @BB. #8 post
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.