If you look at how much time the engine spends running vs on the battery I expect that most will spend relatively more time on the engine than on the battery.

If you look up the energy efficiency for charging you'll see that a NiMH battery in tip top condition will charge for 150% of the energy actually imparted to the battery. So if that becomes 160% then 170% it won't be particularly noticeable. Take a look at one of the links I posted a few days ago.

Unless you set up a controlled set of conditions and do this "test" at some periodic interval, you won't be able to really see it.

In the end I'm using experience with lead-acid batteries to draw an inference as to what we'll see. Lets keep an eye out for what the real world delivers.

 

Guys,
I finally talked briefly with Paul Guzyk, co-founder of 3Prong Power, nice guy, he even called back 3 times (cell phone droppage). They are working on a FEH PHEV conversion... Without getting to specific, he stated that their battery pack controller fools the Prius computer to keep it in EV mode... I'm not sure if they power available is from both battery packs or not... I will email him with more questions, if anybody else has some, pm me and I'll add them to mine... At close to $11K for the 150# Small Lithium pack would take approx. 27.5 years to pay for itself if you drove 20 EV miles a day for 300 days and gas at $3 a gal. Not too bad...hopefully the pricing will improve...we know gas prices won't...
M

 

With most drivers that maybe true but is not the case with me. In most cases in my '05 FEH I have 30% engine run and about 70% EV in a charge discharge mode. This is how I've gotten up to a 70.3mpg 20 mile round trip on flat roads in the '05 FEH. The '09 FEH is just more efficient with the 2.5L with the engine running and charging I don't have to rely on "L" regen to boost battery charging for the 30% engine and 70% EV mode. In other words the '09 FEH is more like a 50% engine and 50% EV mode with better overall MPG. I don't think anyone can dispute my claim with a lifetime average in my '09 FEHL of 48.9mpg on flat roads in 12,000 miles with E10.
http://www.cleanmpg.com/index.php?pa...)&viewcar=2612

The proof is in my results each tank average how the HV battery can operate. My '05 FEH with 60,000 miles seems to be as good as my '09 FEH so far, but time will tell. I drive the hell out of EV mode in both vehicles and will continue to do so.

GaryG

 

I've been amazed at the claims of Plug in packages & how far they'll go EV.

In essence they will fully charge the battery overnight. So you could see the same performance if you could, magically, drive up to your home every day with the battery just completing a charge cycle.

The ability to start out directly in EV mode is good, as is the inclusion of a battery with more energy to deliver vs the NiMH packs.

I'll look up George McDonald's book...

Thanks

 

Bill W,
Which George McDonald? PHEV's are coming soon, So Cal Edison, N Y power,are already testing them..The data should be available? Johnson Controls-Saf, Michigan, is ramping up production to 15 million Li-ion cells.. Hopefully this will bring conversion prices down as they are being partially subsidized by the state of Mich.. I have a question for Gary G: Do you know the average speed for the 12K miles on your 09 and are you traveling at or near the speed limit??
Thanks
M

 

scmike,

I'm ready for batteries with more capacity (& secretly hopeful that Ford will offer a software upgrade opening up the charge-discharge window!).

stevedebi,

Strictly speaking you are correct. My thinking is that the extra charging will be relatively small to the time spent running the engine.

In other words if you get 30 mpg, go 30 miles, and then can go 1.5 miles until restart & recharge, then repeat the cycle on and on... (of course its really not that clean but hear me out).

Then the battery capacity drops slightly so that you go 1.4 miles instead of 1.5 miles, it is almost un-noticeable across, say, one or two years.

Of course if you're one of those that spends alot of time in stop & go traffic you may see it before most. Let me know what you see.

 

SOC Measurement: Terminal voltage tells the story for batteries. An algorithm is needed to measure it dynamically (or with current flow in or out) but it will tell you directly when remaining capacity is 40%. If actual capacity is falling it will read current capacity remaining. Its just the implementation of the electro-chemical process.

In another post I provided a link to a website on NiMH batteries. On p12 of that link the curves of voltage vs capacity were shown. I still believe that is how Ford does this.

The key is that terminal voltage is readable directly and tells the story. If it falls faster over time for a given comparable run then capacity has decreased. I tried to communicate that in an earlier post but was unsuccessful in getting it across.

 

My SGII Tank averages always has a speed average of 24mph but that includes all stops, parking lot speeds and getting up to speed. I also drive the speed limit or near the speed limit in traffic but I will drop down to 30-35mph (not highway) if the road is clear of traffic. My commute can be city or highway so I choose north and south on A1A and US-1 on days I'm not in a hurry and I-95 when I need A/C and have little time to mess around. My biggest problems are when I drive west and back east because those two lane roads have higher speeds and traffic. I pick my routes to avoid traffic and stops. When I must flow with traffic at higher than EV speeds (40mph in the '09), I hit them with a low battery SoC and charge during those segments and go EV ASAP after. Contrary from people posting I drain my battery as low as possible without an automatic restart. The lowest SoC will charge faster than a higher SoC by the generators and this is one of my strategies for higher MPG.

Others may think this is a lot of work but hypermiling is a hobbie that saves gas and emissions for me. My FEH's are stock down to the crossbars and I carry lots of weight all the time. I do most all the shopping which requires lots of stops and cold starts during the day.

GaryG

 

The 19th century author.

 

Well, that doesn't seem to work for me, although I don't P&G or do other hypermile stuff. But my experience is that my best MPG is with the SOC at the normal ~53. At 40 MPH I can get the SGII measured MPG up to 37-42 MPG, which raises the MPG considerably. If my SOC is below 52 my 2008 just dogs it - at 40 MPH I'm lucky to get 30 MPG, and generally it is in the low to mid 20's until the battery is recharged.

Yes, the SOC increases faster when it is low, but my instant MPG (from the SGII) is also lower, because the generator power comes from the engine. I should mention that I have an AWD model; I don't know if it is programmed differently, but it may operate differently from the FWD.