HVB Health from OBDII Data Analysis

[Noah Harbinger]

The hybrid has a maximum charge/discharge limit for the HVB of 35 kW under ideal conditions. When the HVB is very cold or very hot this number will be reduced. Thus the maximum power for acceleration or deceleration in EV mode is 35 kW. The Energi has a 35 kW maximum charge limit but a higher maximum discharge limit. I've seen the max discharge limit as high as 68 kW with a fully charged HVB. As the HVB SOC falls the max discharge limit drops as well. If your HVB is nearly depleted it drops to around 50-55 kW. Once the car goes into hybrid mode with a depleted battery the max discharge limit is usually 35 kW, just like in the hybrid.

 

But my point is that battery depletion/charge rates have nothing to do with whether the motor sizes are excessively large, because they do more than drive from / charge to the battery. So I don't see how your response either adds or contradicts anything I said. 

[hybridbear]

But my point is that battery depletion/charge rates have nothing to do with whether the motor sizes are excessively large, because they do more than drive from / charge to the battery. So I don't see how your response either adds or contradicts anything I said. 

Motor size may be based on the efficiency curve of the motors. The Tesla 85D has more power than the single motor version but can also have lower energy consumption since it has two electric motors which can be tuned for different scenarios. It's possible that Ford's choice in motor size was also focused on having maximum efficiency at the range where the motor is used, <35 kW regen and <65 kW when outputting power.

[Noah Harbinger]

Motor size may be based on the efficiency curve of the motors. The Tesla 85D has more power than the single motor version but can also have lower energy consumption since it has two electric motors which can be tuned for different scenarios. It's possible that Ford's choice in motor size was also focused on having maximum efficiency at the range where the motor is used, <35 kW regen and <65 kW when outputting power.

 

Teslas don't have a power split transmission. 

 

I'm sure power efficiency played a role in the design of it - but not that much. Efficiency on the electrical motor specs I've looked at didn't really drop off until about the top 20% of its torque rating, whereas Snowstorm seems to think Ford is oversizing by a factor of almost 300%! Whereas the numbers you hypothesize seem very reasonable. 

 

I've only just started logging data from the transmission but in my little growler-run out to a local brewery and back, I logged a max 53kWH draw on the motor, and -44kWH draw by (i.e. 44kWH generated from) the generator motor. Not surprisingly (given how a powersplit transmission works), both of those peaks occurred at the same time - when I was accelerating unusually hard (for the purposes of collecting interesting data). It underscores that the purpose of a traction motor rated significantly higher than the battery output is to consume power from the generator motor, sending power through the electrical path to effectively reduce the gear ratio between the gas engine and the wheels. Hence the Transmission role of the motors connected via a the planetary gear set.

Edited April 26, 2015 by Noah Harbinger

[SnowStorm]

Thanks for pointing out the power split role which requires the motor to have a higher rating than what the battery can put out.  So under a maximum power condition the HVB puts out 47 HP (35 kW) and the ICE puts out 141 HP giving the advertised 188 HP total.  The electric motor, however, is getting 35 kW from the battery and some additional amount from the generator.  (BTW, units here are kW, not kWH)  It would be interesting to see battery, generator and motor power under full throttle acceleration from 0 to 70 mph starting with a "full" battery.

[C-MaxSea]

Advanced Vehicle Testing Activity - Idaho National Laboratory. Some updates; "Usage and Performance" through most of 2015.

http://avt.inel.gov/hev.shtml

 

Should this thread be pinned?

Edited January 24, 2016 by C-MaxSea

[fbov]

I think that link has a place in this forum. If only so certain members can go ballistic over the mileage results....

 

43 MPG over 108K miles, with 66% highway

42 MPG over 126K miles, with 71% highway

41 MPG over 112K miles, with 62% highway

42 MPG over 110K miles, with 62% highway

 

... at an average temperature of 84F, running the air conditioner 91% of the time! All four liked 40-50MPH the best, too.

 

HAve fun,

Frank

[djc]

Advanced Vehicle Testing Activity - Idaho National Laboratory. Some updates; "Usage and Performance" through most of 2015.

 

http://avt.inel.gov/hev.shtml

 

Should this thread be pinned?

 

Service info is very interesting.

So 4 out of 4 vehicles needed 12V battery replacement in first few years.

OE tires are lasting 60 to 80k miles.

1 out of 4 needed transmission replaced (at 90k).

Very little else - e.g. turn signal bulb.

[C-MaxSea]

Service info is very interesting.

So 4 out of 4 vehicles needed 12V battery replacement in first few years.

OE tires are lasting 60 to 80k miles.

1 out of 4 needed transmission replaced (at 90k).

Very little else - e.g. turn signal bulb.

 

and in my words / guestimation Extremely Reliable.   :)

 

Nick

Edited January 26, 2016 by C-MaxSea

[fbov]

While I'm impressed that the C-Max battery issues in these SE's were 3/4 under warranty, I also don't call this performance over 100K miles extreme. Continue it for the next 100K and I'll be impressed. Is that reasonable? Let's look at other hybrids (ignoring normal oil changes, tire rotations, etc.).

 

2015 Honda Accord, n=3

Nothing in 30K miles

 

VW Jetta, n=4

66K radiator replaced

10K 12V battery replaced

40K spark plugs

49K battery monitoring control module and rerouted mk wiring to different power source due to vehicle not moving while in gear

7K towed, 12V battery replaced

9K 12V battery replaced

30K replace fuel injectors, fuel pump and pressure sensor, evap vent valve

32K replace evap purge valve

31K replace brake booster, booster sensor

31K (60 miles later) towed, replaced brake booster relay.

42K replaced spark plugs

44K replaced leaky oil plug

85K replaced spark plugs.

 

2013 Chevy Malibu, n=4

111K replaced battery control module

112K towed for dead battery, jump start

117K towed for dead battery, jump start

118K replace 12V battery

120K tighten battery cables and jump start

122K replaced front crankshaft seal

123K towed for flat tire (aftermarket TPMS), jump start, repair cable from battery to fuse block

4K replaced battery cooling fan

9K inspect generator control module - recall

24K replaced generator control module - recall

91K towed to shop, weak 12V battery

92K towed to shop, replaced 12V battery

93K replaced blower motor

99K replaced gas cap to clear "check engine"

120K BCM reprogrammed - recall

120K repaired key, broke off in ignition switch

126K flush AC, replace compressor, drier element and recharge

128K fixed drivers side door panel, resealed oil pan, replaced from cover gasket and crank seal

... and that's just two vehicles, the other two are similar. Clearly a 100K mile car!

 

2013 Honda Civic, n=4

28K AC compressor

100K wipers, air inlet cover, drive belt ,radiator hoses, thermostat

165K replace 12V battery

 

2011 Hyundai Sonata, n=2

Nearly identical and flawless, until

120K diagnosed for low 12V battery. Motor inverter fault, inverter shorted. Cost $10,000

 

Changed my mind. Our C-Maxs are EXTREMELY RELIABLE

Edited January 27, 2016 by fbov

[plus 3 golfer]

With regards to the 12 V batteries being replaced in the test C-Maxes, one needs to understand that the tests are being conducted in the Phoenix area and batteries simply don't last as long in the severe Phoenix heat as in milder and colder climates.    I replaced my C-Max battery at about 2 1/2 years of ownership.

 

In my nearly 9 years of living in the Phoenix area, I had to replace six - 12 V batteries in my vehicles.  Since I always owned 2 vehicles at any one time, that's a battery replacement on average about every 3 years per vehicle.   So, IMO the 12 V battery replacements in the test C-Maxes are indicative of normal shorter battery life when in service in very hot climates.

 

Here's a map of battery life that I posted previously.

 

Edited January 27, 2016 by Plus 3 Golfer

[fbov]

That explains why I expect a car battery to last 5-10 years... I live where they do!

[C-MaxSea]

Hah, LOL, that is funny Frank; I was actually being a little facetious with the "Extremely Reliable" note.  Facetious because we spent a year or two hearing only the opposite here.  Logically much of that 'unreliable' stuff was based on new and unfamiliar technology - some fluky electronics to be sure, and granted we've had our share of recalls; but none the less (and save the lemons), a very reliable vehicle (perhaps even "Extremely" over time, especially considering the 'high' tech aspect). New tech meets new hybrid drivers guaranteed spotty early reporting.  Thanks for detailing some of the comparative results from other 'less reliable' makes/models.

 

Thanks Plus 3 for that great battery life note - a reality check to be sure on batteries.

 

Sure glad we have some 100K+ reporters here to remind us of what might be ahead on trannies ................... ponder those Extended Warranties .................... hoping for some 200 & 300K'ers in time.

 

Nick

 

(PS  Love our trannies; quiet, silky smooth ......... love !!!)

Edited January 27, 2016 by C-MaxSea

[fbov]

...Sure glad we have some 100K+ reporters here to remind us of what might be ahead on trannies ...

I thought you were being facetious, until I started looking at the service records.

 

The tranny thing is interesting... I'm also a long service owner, who's wants lots of miles on the existing tranny. To that end, I think Ford's yearly PCM refresh is fine tuning the system's operation to avoid catastrophic failures. Bearing failure modes are well known, so I discount a major design flaw in favor of a usage pattern that promotes a failure. Taxi tranny failures were an early warning. PCM update effects are another.

 

The biggest change I've seen is the inability to access ICE after a cold start. ICE runs, but no matter how low the battery, there's no ICE motive power until the top of my street. Seems like a good way to reduce stress on something until the engine warms...

 

HAve fun,

Frank

[C-MaxSea]

Frank,  ......... and to muddle clarity even further; keep in mind I said "a little facetious".  IOW, I do believe the C-Max to be very reliable, a bit fluky at times, but very reliable.

 

Re: trannies; I would not trade our C-Max tranny for any other similar, even knowing there is a remote chance I have to replace it someday - the car & tranny are way too good to fret a little replacement like that.

 

Having Fun,  :skateboard: :skateboard: :skateboard:

 

Nick

Edited January 28, 2016 by C-MaxSea

[hybridbear]

The biggest change I've seen is the inability to access ICE after a cold start. ICE runs, but no matter how low the battery, there's no ICE motive power until the top of my street. Seems like a good way to reduce stress on something until the engine warms...

This is for emissions purposes only & actually results in increased fuel consumption. Check out the Warm Up Stages thread for more info - http://fordfusionhybridforum.com/topic/7408-ffh-warm-up-stages/

[fbov]

Have you updated it since 14E02? That's when I first noticed this change on start-up. And I have an warm-up operating mode you don't list.

 

You can tell when S1a ends because the ICE begins providing the power needed to propel the car and charge the battery.

Per your stage criteria, S1a ends at the top of my street, perhaps 100 yards away, no more.

- EV power in engage goes to zero,

- charge carat switches from discharge to charge

- engine speed rises and engine is louder, consistent with load.

 

I'll pay attention on the cold days to see if S1a makes it around the corner. No way I'm near 40C that fast after a -10C night!

 

And then there's the missing a mode. I would call it "limited EV" mode, characterized by S2 operation, but with a 1-bar ICE threshold that is independent of HVB charge level, but depends on coolant temperature. When using heat, this is the transition mode between S1b and S2, and one that transitions back and forth. As coolant temp falls in a glide, the threshold will drop to 1 bar before dropping to zero (ICE on). As coolant temp rises after a burn, the threshold will rise to the normal SOC-dependent 1-2 bars EV.

 

Now, if I leave the heat at 60F, this doesn't happen, the car works as you describe. Once I'm in S2, bumping the heat even 2 degrees results in a 1-bar ICE threshold until the engine is warm enough, but it reverts when it cools. It makes for really long glides with a little throttle discipline, and really few EV miles without!

 

Your thoughts?

Frank

[hybridbear]

Have you updated it since 14E02? That's when I first noticed this change on start-up. And I have an warm-up operating mode you don't list.

No, that's the problem. We have an Energi now & we only use the ICE on long trips. We've never started our Energi cold with a depleted HVB & it's been a couple years since we had the FFH now.

[fbov]

We all move on, eventually. I've appreciated your input, and thank you for your contributions.

Frank