Okay... this touches on something that annoys me with plug-ins. It gets 52mpg on EV only.... Um... if its EV ONLY why the heck isn't it 1,000,000,000 MPG! Its EV ONLY... the gas engine supposedly never ran, i.e. EV ONLY! MPG is kind of useless on plug-ins. Sorry. It all depends on how long they go on the battery alone!

Incidentally... my guess is you mis-typed or misread the article. I think the article says they can go 52 MP-HOUR on EV only.... not MP-Gallon. Big difference.

 

I do have to defend him by saying that there ARE numerous chips/devices to provide "fuel guages" for NiMH/LiIon batteries on portable devices that do EXACTLY that... try to "count coulombs". They actually integrate the current flowing into and out of the battery. They get over the issues you mention by periodically "recalibrating" the device.

I can't say that is practical on the scale of Hybrid Vehicle battery... but coulomb counting isn't exactly a joke... at least not on the scale of a small battery with just a few cells.

I actually looked into building such a "fuel guage" on a handheld device I worked on by using these chips. In the end we went with just looking at voltage and decided it was "good enough".

 

A little off topic, but you remind me of my favorite approximation in the FEH. The water temperature is calculated from (I believe) the cylinder head temperature. This is the first vehicle I've had that didn't have a water temperature sensor - so far as I know. I suppose it is possible that my last vehicle, a Ford Freestyle, also calculated the temp.

 

I'm gonna stay out of the battery fight, but for the recall I suspect a call to any dealer with the VIN could answer that, but if you register it at MyFord.com it may also. I believe it tracks my vehicles, but (knock on wood) I haven't had the 08 in for a recall yet. (altho the AC Blend door should be one!)

oops it's http://www.flmowner.com/servlet/Cont...mePage&lb=ford

 

batteryQuick one; What is the FEH HV bat. pack voltage fully charged and what does the voltage drop to before restart?? I have/had a dozen 18V DeWalt ni-cad packs (14 C size ni-cads) and new they top out at 21.4V to around 20.0 at 4 or 5 years semi-regular use.. so down about 6.5%.. Older bat. packs with go down to about 13.5 which is a pretty dim flashlight and past when I would normally charge them.. Anyway, will an older FEH battery back show a similar voltage drop or approx. 308.5V if 330V is a fully charged new pack??
Thanks
Mike
P.s. Sorry about the 52mpg typo should have been 52 mph which is amazing, I think for EV only in a Prius... And lets save the Zero's we are getting infinite mpg's in EV mode...

 

Coulomb counting is otherwise known as:

Inserting a calibrated shunt into the circuit, measuring the voltage drop across it relative to time, integrating that result, and displaying it in some form such as amp-hours.

Give me a break guys.

And don't forget that the amp-hours available varies with discharge rate and age of the battery.

There is one trouble with this method: it doesn't really tell you the remaining energy in the battery. ...And that is what you want to know.

You know, the chemistry of the NiMH battery is well understood, the electrochemical values can be correlated to capacity available, corrected for current effects, and this can be directly interpreted as a % and displayed as such.

This method requires no correction for age or discharge rate and if the amount of energy available changes for some reason the computer knows just how to handle it.

My bet is that as these cars age the endurance (at some kind of consistent speed) from the high charge level to the low charge level will become shorter & shorter (on a scale of years) but the % will remain the same. Think about it.

 

With regard to "exact" as in "always" and "without exception..."

You don't understand how things are measured, displayed, and recorded (where needed).

I'll bet you think that your watch is a world wide standard. (I do suppose that you can purchase one of those watches that syncs up with WWV...)

All measuring systems have errors. All readouts have interpretation errors relative to the input signal. Since higher & higher accuracy costs money the question is: how much accuracy do you want to pay for? (Or how much accuracy is Ford comfortable making you pay for.)

You're like the guy that represents himself in a court proceeding. Remember that old saw about the client?

 

Well, I haven't heard any complaints of Hybrid owners that their MPG is getting lower as the vehicles age, and I would think that such a fact would be prominent. I have seen sporatic reports of lower MPG, but not broad spectrum reports.

The current FEH keeps the SOC between 40 and 60%, allowing a pretty free discharge between these two levels (from what I can tell by posts from 2009 FEH owners - I have a 2008); the pre-2009 was even more conservative in SOC use, keeping the SOC at around 53%. The HSD uses more SOC, but I can't really say how much because I don't own one. But the reason the manufacturers used HiMH and conservative settings was to make the battery packs last.

 

Bill doesn't get what we're talking about...and from the sounds of things, he doesn't even want to know how this car works.
People like him tend to be very narrow minded.
You can tell he has some very specialized formal education, but you can also tell from his posts, he has not recieved a well rounded education.
This is working against him.

He sounds quite abrasive in his posts.
Try not to take it personally.

For those new comers just joining us... Bill does not believe in gravity. Although every apple that has ever been viewed to break loose from the branch of a tree has always fallen towards the earth... Bill claims since every apple has not been viewed, it is premature to assume that apples will always fall from trees towards the earth. Bill says it would be much simpler for the earth to move towards the apples, since there are many apples, and only one earth, and therfore, that is likely what occurs. Bill likes mind games. Bill does not like reality.

Bill will tell you he knows everything about me, while I know nothing about him. Bill can't even read my posts correctly.... God bless him....

 

Bill doesn't understand that binary systems are "exact".

They are on, or off. Up or down. Left, or right. 1 or 0. True or false.
There are no decimal points required.

The rules I stated for the FEH are "exact".
I'm more than aware that nothing in nature is "exact" and no physical measurement is "exact". I never said it was, and I even clarified this later. This is why I have to conclude Bill can't read.

To illustrate, an example: the better you measure the coastline of the U.S. the longer it gets. Some people say the length of the U.S. coastline has a finite length, and the better you measure it, the closer you get to the "real" number. There is no "real" number. People who understand what I'm saying know the length of the U.S. coastline is infinate.

Rule:
If Battery calculated SOC > 40% = true, then engine can be off, if able
If Battery calculated SOC > 40% = false, then engine must be on, if able

What the 40% actually means is not part of this equation.
The rule above is exact, and without exception.*
* In 4.5 years, no exception has been observed, and a reasonable, rational person would consider this to be as fact without being the author of the software.