planet4ever said:
edatoakrun said:
planet4ever said:
First, you do not know that you had the same number of kWh. None of the data available to you is precise enough to guarantee that...
I didn't derive that the kWh charge was constant from from any "data". I was observing a battery that was not charged, or (significantly) discharged, and watched the 10th bar appear and disappear as it correlated to ambient temperatures.
OK, I missed that. I withdraw my first point.
edatoakrun said:
This could be because as warmer battery warms it now has a larger capacity (as expected) and each one of the bars in the display now represents the same amount of kWh, but rounded to the nearest ~12th ...
Here is where you and I part ways. I insist that the bars in the display do
not represent the same number of kWh as the capacity changes, so I have not, as you claim, "restated one of the possible explanations that I mentioned above."
The key point that I must repeat is that a charge bar is not a constant number of kWh. It is a variable amount depending on both battery temperature and battery age. It is a constant fraction of the maximum allowed charge at that instant in time. (Note: I am not saying that all charge bars are the same constant fraction. I believe some bars may "hold more" than others.) Perhaps you need evidence of this assertion. Pages MWI-26 and MWI-27 in the service manual (April 2011 edition) spell this out in excruciating pictorial detail. Here is one of several examples:
Ray
OK, I can see why my attempt to explain bar variability was poorly worded, and I misled you.
Obviously, each bar does not represent an equal amount of kWh, whether of a twelfth of fourteenth of total capacity. My use of "~" was intended to convey this variance of kWh content of the different charge bars, from one to twelve, but I realize now my statement would be understood as you have stated.
My error.
However, I don't (entirely) accept your statement:
"...The key point that I must repeat is that a charge bar is not a constant number of kWh. It is a variable amount depending on both battery temperature and battery age. It is a constant fraction of the maximum allowed charge at that instant in time... "
I think we both agree that whatever that "maximum allowed charge" is,
the total kWh of that charge will be constant, and the bar display will vary with temperature, as illustrated in the manual.
But I do not agree that your statement that "...It
is a constant fraction of the maximum allowed charge
at that instant in time..." has been proven to be correct.
The total charge is a constant, but the fraction represented by each bar may not be.
In fact, I think that if gid count varies with temperature changes on a battery that is neither charged or discharged over the course of observation, that would tend to indicate very strongly that any bar is
not a constant fraction, over varying temperatures.
It would also provide additional data on the subject of gid variability with temperature, which could be very useful for answering other questions, accuracy of the
capacity bar display, being the most, significant, IMO.
Which is why I think this would be a very useful observation for those with gid meters to make, and report the results from.