Happy New year Flux,
I'm hoping Bzrqmy is working on the next practical step in AH to a true SOC.
Navy, 1Mw battery had AH accumulator. NO sign. We controlled power in/out for the most part. Knew SOC relatively well. Including 4 hour discharge curve for it, we were willing to kill it if necessary. Never went below 70% SOC, people starting freaking out around then.
Solar / wind charging is never a complete charge or discharge cycle.
By modeling the battery based on SOC, temp, charge/discharge rate, time, age etc. the SOC can be more accurately determined than using AH.
4 years ago started out on this road, needed to estimate SOC for automotive battery.
Signed charge accumulator and Peukert number were a good starting point.
Vehicles battery is usually fully charged, simple starting point each cycle.
Tossing in Temperature, Peukert numbers gave us acceptable SOC. Project completed. Wanted to extend the work to RE (personal project), worked on it for a couple days, realized did not know enough to make it work, to busy to work on it further. Collecting info since to understand how it could be done. I like to model things, got my wind turbine model to correctly predict power into the battery.
SOC battery indicator for RE is more complex.
AH may be 20% accurate over a shorter time, longer charge/discharge cycles less accurate. Quickie AH on discharge side is rather accurate.
Peukert is a first level calibration factor, over time will not cut it for RE.
Surprising how little recent information about LAB modeling out there.
Considering LAB (of some type) represents 60% of the battery market.
If battery is modeled correctly expect it to tell you when to water it! When to turn on the fan.
Performance of the battery is dependent on battery construction.
Manufactures do not spell it out, any attempt at SOC must figure this out over time.
SOC indicator must be bonded to a battery. Connecting it from the start will be as good if not better than AH.
AH is SWAG. SOC better than 5% long term is possible. (I believe)
Long term small errors grow, destroying accuracy. By modeling the battery correctly, can nullify the errors based on measurable conditions: Current, voltage, temperature and time.
Not easy, else it would have been done. Someday will take this project on myself, many other projects in front of it. #1: Extracting water from air.
Willing to spend time helping someone else do it. Testing is the big time sink.
Not heard from Bzrqmy, maybe he was scared off or does not believe I can help!
Have fun,
Scott.