ksoul2084 wrote:I find the SOH to be fairly misleading, not really sure what it's telling me?
As you have experienced, BMS battery balancing and recalibration can result in a updated evaluation of battery state. If it has been a long time, or a long distance since last time you discharged to around 10% and charged back up to 100%, the change can be significant.
The SOH is calculated using the mean of the two values indicating lost capacity: min and max det. I don't know if the calculation is the same as used by Kia, so the app may not produce the same SOH value as an official test at a Kia garage. That value is the goal for the SOH calculation in the app, but I need some app-recorded files with min and max det from shortly before and after a Kia SOH readout, as well as the official Kia SOH. I can improve the SOH calculation if I get a few such datasets, at different levels of SOH, and significantly different min and max det, like your car's values.
ksoul2084 wrote:I find the Battery SOC prec(ise?) value to be a better representation of my overall battery state of health, since when the battery is at 100% SOC, it seems to how the actual available percentage of the battery vs. when it was new.
So on my soul battery SOC at 100% , SOC Prec = 58.72%. In my experience this represents an accurate estimation of the range I will get from the charge.
SOC Prec 100% = 150kms range (when new).
SOC Prec 58.72% = 88kms range now (what the GOM typically shows).
Of course, depending on my driving habits I can squeek up to 110kms out of the range, but typically no more than 100kms.
I am glad you find "SOC prec" useful. I haven't found and explanation of what this value from "PID 598" actually is, see https://docs.google.com/spreadsheets/d/ ... =234054559
So your guess is as good as mine. On a new car with 100% SOH, it seems to follow the SOC fairly well, so you may be correct in this value indicating the actual / expected amount of energy currently stored by the battery. I am interested in knowing more about the nature of "SOC prec" as well. Perhaps I should do some number crunching on the data I have gathered from my car 2017-2019, if I can find the time for it.
ksoul2084 wrote:So what good is SOH? Do others find SOC Prec to a better indicator of overall battery health?
The SOH is useful for determining whether to visit Kia for a warranty check. But as you have demonstrated; you need to perform a BMS battery balancing and recalibration first: Kia will undoubtedly start by doing that, if you ask them to test the battery.