The SOH "health" is some unknown number, so it is not
clear how it should match anything else. If it measured
or estimated the same properties as AH, then there
would be little mystery, and we might just say that
these are two different ways of estimating things.
However, at this point we do not even know what
this number attempts to estimate. Perhaps it is
some measure of the average cell resistance,
compared to a "good" battery?
We have not yet found the 96 calculated cell
resistances yet, as far as I know.
Similarly, some also try to compare SOC with other things,
like the SOC and AH/65.x values. These two readings
measure different aspects of the car, and should not match.
How do you say... like comparing fruit?
SOC is a measure of how full the tank is right now.
When you fill the tank, no matter how much
the tank has shrunk, the SOC is about 95%, and
it drops down toward 5% (or so) as you drive,
gradually emptying the fuel tank.
AH is apparently an estimate of how much current could be
poured into the tank, not how full it is now, or how much energy
is in the tank. If one assumes that a typical new, full-capacity
battery could hold 65.47654 amp-Hours of current, then
one might consider this AH/65.xx as some sort of estimate
of the battery's capacity. But, the initial estimate and
assumptions make it... not perfectly reliable.
If AH/65.x should be around 100% when the battery is new.
and around 85% when you lose one capacity bar, how
does that compare to the "full" SOC, which is still around
95% in both cases?
Answer, it doesn't, and shouldn't match.
Like Pickles and Squash, I say!
