Cmax doesn't seem to use battery power that much

[Taiwwa]

Just got a used SEL model with 60k miles for about 12k. 

 

Pretty nice car so far.

 

I've noticed that the car uses the gasoline engine where I think it should be using the electric, and the electric where gas might be more appropriate. Like, when climbing up an incline, sometimes it will switch solely to gas. Sometimes lightly accelerating on the highway, it'll use the electric motor.

 

Looking at the battery, a few things. The electric engine never goes all the way full power. When it goes up, it'll stay up and then quickly change over to gas. The battery is never drained below 50%. It is often 100%, more than is appropriate IMO. 

 

Overall, great gas mileage compared to what I was driving before. In the same area I was driving around a Subaru outback and was getting maybe 19MPG at best. I get between 37 and 40MPG in the city. Still, it could be better, could it not? Why is it so hesitant to use electric?

[WNY]

First, do you have the Cruise Control on the menu system set to ECO mode. When you put it on Cruise, does the ECO light (green) come on also? 

 

Yes, if you accelerate too quickly on Battery only power, the electric motor doesn't have enough power to accelerate the car fast enough, so the engine will kick on.  

 

The Battery/ICE (engine) will switch automatically depending on the load on the engine and engine temperature.  the electric motor will help when it's on level ground and if it needs more power going up a hill.

 

Yes, the battery will run typically between approx 40-100% on the gauge (not actual battery state of charge). it normally runs between 30-70% all the time when running in hybrid mode. it will never discharge fully. It may go down a little more when you get near your home or work (in EV+ mode). 

 

Sometimes it will be fully charged if idling or going down hills or a lot of braking with no power needed.

 

The Up and Down Arrows on top and below the battery icon tells you when it's using power or charging. 

 

Check your tire pressure, most of us run 40+ psi in the tires. that helps a little bit on mileage. 
There's some good posts on here for maximizing mileage. 

Edited December 8, 2015 by WNY

[plus 3 golfer]

There's a lot that has been discussed on these subjects. Bottom line your car seems to be operating normally. ;)

You can control the use of ICE (internal combustion engine) and the High Voltage Battery to some extent with the throttle and your driving style - again much written on how to do it. Cold weather significantly affects operations as ICE will run to get up to a minimum operating temperature for emissions purposes and to maintain operating temperature. So, ICE will be charging the HVB much more on startup and short trips in colder weather and hence why the battery symbol might show near full a lot of the time.

The normal operating range or State of Charge "SOC" of the HVB is generally between 40%- and 55%+ (not the battery symbol) of the installed 1.4 kWh capacity. Generally, regenerative braking or ICE must run conditions will charge the HVB above about 55 %. Use of EV+ can discharge the battery into the lower 30% range. The operating range of the HVB is limited so that the HVB will last a long time. When the battery symbol show full (including the tip), the HVB is at about 70% State of Charge . When the battery symbol shows near zero, the SOC is around 30%.

Edited December 8, 2015 by Plus 3 Golfer

[raadsel]

It's also worth noting that the battery indicator on the dash is not the actual battery charge -- zero on the dash indicator is around 30% charge on the battery, 100% on the dash indicator is only about a 70% charge on the battery, at least from what I can recall. You can see the actual battery charge using the OBD2 port and a reader that has the codes for the hybrid battery charge.

[Adrian_L]

From my experience, the car runs on the HV battery about 60% of the time.  I'd say that was more than "not that much".

[Marc Smith]

Taiwwa

 

This time of year, Winter, is the worse for fuel milage.  the winter fuel is not as energetic as summer fuels,  plus the engine must run to make heat for the cabin.  so if you have your heater set high  the engine runs more.    I use the seat heater to get my butt warmed up.  But my car is also garaged  which helps keep it a bit warmer than if it was kept outside.

 

I had a prius before the cmax  so I got to learn how to drive a hybrid to maximize the mileage.  Yes you can drive the hybrid like a regular car and get ok milage.    but with  a hybrid,  driving "calmer".  coasting up to a stop light,  easing off the gas as you near the crest of the hill and let your momentum carry you over   using the electric motor on the down slope to accelerate to increase you speed to have more momentum for the next hill.  will result in much better mpg.

 

speed limits....stick to them.  much better mpg, but you may experience hybrid rage from the other drivers.

 

I notice you are in  west VA.  I live in Vienna VA,  so if you were in the neighborhood and wanted to compare mpg on a route....

[scottwood2]

If you want to increase the MPG there are a lot of driving tips on this site to do that.   Some people like that and others just want to drive the car.   It is up to you but as others have said there are many many posts here on technique for increasing MPG if you want to go that route.  Took me months to learn what and what not to do to get better MPG.  Mainly it is city driving techniques.  I find Eco-cruise on the highway fine for most of the time. 

[fbov]

First, do you have the Cruise Control on the menu system set to ECO mode. When you put it on Cruise, does the ECO light (green) come on also? 

 

Yes, if you accelerate too quickly on Battery only power, the electric motor doesn't have enough power to accelerate the car fast enough, so the engine will kick on.  

 

The Battery/ICE (engine) will switch automatically depending on the load on the engine and engine temperature.  the electric motor will help when it's on level ground and if it needs more power going up a hill.

 

Yes, the battery will run typically between approx 40-100% on the gauge (not actual battery state of charge). it normally runs between 30-70% all the time when running in hybrid mode. it will never discharge fully. It may go down a little more when you get near your home or work (in EV+ mode). 

 

Sometimes it will be fully charged if idling or going down hills or a lot of braking with no power needed.

 

The Up and Down Arrows on top and below the battery icon tells you when it's using power or charging. 

 

Check your tire pressure, most of us run 40+ psi in the tires. that helps a little bit on mileage. 

There's some good posts on here for maximizing mileage. 

Someone's been listening...

 

Two things I haven't seen mentioned.

 

DASH FEEDBACK

Select the left side display that tells you the most (see Information Displays in the manual). There's a menu of selections (trip odos are here) and under "Display" a series of hybrid powertrain informational displays. Many of us use EMPOWER as the base display, for it's "Blue Outline" showing available EV, along with a blue bar of what's being delivered.

 

Getting this feedback between your right foot and the drivetrain state enables much better fuel economy. The first secret to mileage is being able to select when you stay in EV mode, and when you use the ICE. Your right foot is the control.

 

EV LIMIT

You will never get more than 2 bar of EV when running on battery. Yes, there's 88KW of generator capability in there, and a 1.5KWh battery, but the best you'll ever get is 2 bar of EV when running on battery because peak battery power is 35KW. The reason is Ohm's law, Power = current x voltage, and let's say the system's running at 350V (ballpark range). 35KW is 100 Amps at 300V. My house has a 240V, 200 Amp service, for comparison, and do you think I've every used all 48KW?.

 

Then consider the battery is DC, the motor/generators AC, so that 100 Amps isn't flowing through a wire, but rather a DC-AC converter. You should temper your expectations about EV mode; this is not a Tesla.

 

Once you establish the link between hybrid state and right foot power requests, start to think of driving in terms of energy use. Here's a model of hybrid driving.

 

When using ICE, you take energy out of the tank. You can put that energy either into the battery, or into energy of motion, kinetic energy.

 

When you drive up hill, you store kinetic energy as potential energy. When you use regen braking, you store kinetic energy as electrical energy.

When you drive down a hill, you release potential energy as motion. When you use EV, you release the kinetic energy stored from braking.

 

The final piece is engine efficiency. Low RPM and high load get the most energy out of each gram of fuel. The metric is "brake specific fuel consumption" or BSFC, if you want to learn more.

 

Now, you live in West Virginia, which is fairly hilly. I live just South of Lake Ontario, where it's fairly flat. We'll likely have very different optimum driving styles as a result of the differing terrain. I can charge-while-accelerating uphill most of the time, if I'm patient, and coast on EV down hill. With steeper hill, you need regen to control speed on the downhill side, so you have to use EV uphill, to make room in the battery! Knowing if it's about to flatten out makes knowledge of the route important too.

 

I treat it like a game.

 

HAve fun,

Frank

[Taiwwa]

So I went on the exact same stretch twice today. It was a short distance. First time...battery power was used a lot, I get 60 mpg reading at the end. Second time, more ICE, I get 26mpg.

 

Yeah, I see how you can sort of trick the engine into going to battery mode by easing up on the throttle when it is ice and then revving back up.

 

It is kind of disheartening to see the car going in battery mode up the hill...then when the battery hits around half it just quits and the ice fires up. Since zero is not even really zero but 30%, I'd have expected it to go all the way to the bottom. And even then, at least be partially running. About 2/3rds up the hill the electric completely cuts out even though it still has at least 40% on e bar, which is really like 60%

[Marc Smith]

so just on those two trips,  your average is 43.... not horrible  since its winter time fuel, and cold outside temps (which uses ICE to heat the cabin)  also keep in mind that if you have the windshield defroster(ac) on you are eating up battery power as well.

 

on my trip to work in the morning  I can get low to mid 50's  but coming home exact same route, its low 40's to high 30's.  if you look at my fuelly  chart you'll see that early on my mpgs were down low 40's, when I first got my c-max.  call it the learning curve of the car.  Sicne I had a prius before  I already knew how to drive to a hybrid...sort-of

 

terrain  place a big part in our neck of the woods.  hills  can help you in one direction,  but kill you when you go the other direction.  and it doesn't need to be much of a hill.  even slight grades  that you may not notice as a driver,  your call will notice..

 

I keep my display on the "engage"  display.  and when I accelerate  with the ICE  I try to stay a round the second line.  there are two schools of thought.  accelerate slow and get better MPG with out really revving up the ice, or accelerate quickly to get up the speed and ease off the gas  and the begin  what folks call pulsing and gliding.

[plus 3 golfer]

So I went on the exact same stretch twice today. It was a short distance. First time...battery power was used a lot, I get 60 mpg reading at the end. Second time, more ICE, I get 26mpg.

 

Yeah, I see how you can sort of trick the engine into going to battery mode by easing up on the throttle when it is ice and then revving back up.

 

It is kind of disheartening to see the car going in battery mode up the hill...then when the battery hits around half it just quits and the ice fires up. Since zero is not even really zero but 30%, I'd have expected it to go all the way to the bottom. And even then, at least be partially running. About 2/3rds up the hill the electric completely cuts out even though it still has at least 40% on e bar, which is really like 60%

You can get very different results depending on the SOC when one starts the trip and ends the trip on short identical trips.

 

Operations of the Hybrid system is designed to ensure long HVB life while taking advantages of efficient charging by ICE of the HVB.  The hybrid algorithms can't look ahead as to future road conditions and your possible inputs.  So, you as the driver have to anticipate conditions and control the use of ICE and the HVB to some extent to squeeze out more efficient Hybrid operations (hypermiling). For example, you might be able to back off the throttle going uphill to allow EV operations all the way to the top and regenerate coasting down hill.  But, if the algorithm continually allowed the cycling of the HVB down to 30%, HVB life would likely be reduce. So, there are limits in the algorithm.  If you watch the Empower screen you will see that the load threshold for ICE coming on drops as the SOC declines.  At 40% SOC it doesn't take much load to trigger ICE on.  Unless you reduce speed (on the flats and especially uphills), ICE will likely come on.

 

Also, below is a graph I plotted from actual data.  You can see that 40% on the dash battery symbol is about 42% SOC of the HVB not 60%.  

[Taiwwa]

It isn't cold at all. Yesterday and today temps have been in the high 50's/low 60's.

 

I'm guessing that with Lithium batteries, there is also reduced power as the battery is drawn down also? Might explain it?

 

I'm not quite seeing how this hybrid system is all that different from the Honda Insight system. I'm actually quite surprised by how often the ICE engine goes it alone. 

[markd]

If the hill isn't that big and you don't have anyone behind you you can slow down and use more battery. After a year I find that I can do better than the eco cruse most of the time. In the mornings the ice is going to run so I run the heat, once the car is warmed up I turn it off, it usually only takes a few miles. I hope you have as much fun learning you car as I have with mine.

[ptjones]

It isn't cold at all. Yesterday and today temps have been in the high 50's/low 60's.

 

I'm guessing that with Lithium batteries, there is also reduced power as the battery is drawn down also? Might explain it?

 

I'm not quite seeing how this hybrid system is all that different from the Honda Insight system. I'm actually quite surprised by how often the ICE engine goes it alone. 

When you first start out you will have two functions that will automatically happen, first at 35mph the ICE will start even when the ICE is hot, this is to lubricate the trans., second the ECM wants to get ICE  WT to 128*F before allowing EV operation.  So quite often I will start out in EV Mode from my house and accelerate to 35mph depleting the HVB in the process then recharge HVB while ICE warms up to 128*F.  You might consider Grill Covers to heat the ICE up faster and improve your mpg's.  :)

 

Paul

[djc]

Even when the ICE kicks in going up hill or accelerating, the EV system may continue to provide propulsion (reducing current fuel consumption), or the ICE may also be charging the HVB.  Look for the up and down arrows over the battery state-of-charge gauge.

 

Golfer, along with the great real vs displayed battery SOC chart,  said " The hybrid algorithms can't look ahead as to future road conditions and your possible inputs."  

True, but this could be otherwise.  Most of us drive the same routes again and again, and a smarter "EV+" mode, using the car's built-in gps, could know when familiar hills and on-ramps were coming up.  I am guessing future hybrid systems will smarten up in just that way.

I'd also like a "max EV only acceleration" position on the throttle, say a click, so that driver has easier control over switch to ICE.  It can't be good to keep eyes on left dash gauge rather than road.

Edited December 13, 2015 by djc

[ptjones]

With the ScanGaugeII  I don't have to look down. Watching Smart Gauge HVB gauge even at 32%SOC the SG registers 20%, at 40%-50% SOC SG reads about 50% and 60%SOC  SG reads close to 100%.  I have seen 80%SOC after sitting over night in the garage, it had 55% SOC when shut it off. :)

 

Paul

[Taiwwa]

You know, the funny thing is that the battery is still subject to the laws of conservation of energy. So ultimately, all power is going to come from gasoline one way or another.

 

Anyways, I've pretty much given up on trying to game the system. I mean, even if it weren't a hybrid, it is still a CVT transmission. And it seems every time I consciously try to hypermile the car, I end up with MPG that is about the same if I drove it normally.Just treating the car as if it were a normal car, heck, I got 47.5 MPG on my last trip and hour each way. And it drives really well, and has lots of space too. 

 

If I had a Ford Focus instead, I would have gotten maybe 26-27MPG on the same stretch. My Subaru Outback was lucky to get 19MPG. 

Edited December 13, 2015 by Taiwwa

[ptjones]

You know, the funny thing is that the battery is still subject to the laws of conservation of energy. So ultimately, all power is going to come from gasoline one way or another.

 

Anyways, I've pretty much given up on trying to game the system. I mean, even if it weren't a hybrid, it is still a CVT transmission. And it seems every time I consciously try to hypermile the car, I end up with MPG that is about the same if I drove it normally.Just treating the car as if it were a normal car, heck, I got 47.5 MPG on my last trip and hour each way. And it drives really well, and has lots of space too. 

 

If I had a Ford Focus instead, I would have gotten maybe 26-27MPG on the same stretch. My Subaru Outback was lucky to get 19MPG. 

What speed were you driving on the FWY and OT? :)

 

Paul

[Taiwwa]

What speed were you driving on the FWY and OT? :)

 

Paul

Freeway speed limit is 70mph. It usually drive around 65. At times I hit 80 when I hit a fast group of cars.

[ptjones]

Freeway speed limit is 70mph. It usually drive around 65. At times I hit 80 when I hit a fast group of cars.

What about OT(outside temp). :)

 

Paul

[Taiwwa]

What about OT(outside temp). :)

 

Paul

Oh, pretty warm. Like 50's or 60's

[ptjones]

Oh, pretty warm. Like 50's or 60's

I would say that is very good Hypermiling FE without Grill Covers and wheel covers. It would seem to me your CMAX is working just fine. :)

 

Paul

[plus 3 golfer]

You know, the funny thing is that the battery is still subject to the laws of conservation of energy. So ultimately, all power is going to come from gasoline one way or another.

 

Anyways, I've pretty much given up on trying to game the system. I mean, even if it weren't a hybrid, it is still a CVT transmission. And it seems every time I consciously try to hypermile the car, I end up with MPG that is about the same if I drove it normally.Just treating the car as if it were a normal car, heck, I got 47.5 MPG on my last trip and hour each way. And it drives really well, and has lots of space too. 

 

If I had a Ford Focus instead, I would have gotten maybe 26-27MPG on the same stretch. My Subaru Outback was lucky to get 19MPG. 

 

It isn't cold at all. Yesterday and today temps have been in the high 50's/low 60's.

 

I'm guessing that with Lithium batteries, there is also reduced power as the battery is drawn down also? Might explain it?

 

I'm not quite seeing how this hybrid system is all that different from the Honda Insight system. I'm actually quite surprised by how often the ICE engine goes it alone. 

 

The C-Max transmission is not a conventional CVT like the Honda Insight uses.  The Insight runs in Parallel Hybrid mode.  The C-Max uses a power split transmission like the Prius.  Thus, the C-Max can run in Parallel Hybrid mode and Series Hybrid mode which IMO allows more "gaming" to increase FE.  IMO, learning the tricks can increase FE.  But it does take a little work / discipline to continually "hyper-mile" to achieve better FE - some like to do it others like me don't. :)  I also find that when I do hyper-mile, I decrease average speed from when I set eco-cruise 3-5 mph above the speed limit and thus add time to trips.

 

With respect to "there is also reduced power as the battery is drawn down also? Might explain it?" , my guess is that although there may be some loss in maximum power output of the HVB as SOC declines, over the SOC normal operating range in question, the decline in the threshold level of when ICE comes on is more related to controlling the rate of discharge in EV mode once a certain SOC level is reached and holding in reserve enough HVB capacity (energy) for perhaps "emergency" situations like WOT acceleration.  

 

If you look at the discharge curves for Lithium Ion batteries (assuming the C-Max curves are similar), the voltage is fairly flat in the mid range of SOC at a fixed discharge currents.  If more load is placed on the battery, voltage drops and current rises.  So, the load requirements can still be met at a wide range of SOC.  There is a knee to the discharge curve (voltage vs SOC) that once exceeded the voltage will rapidly approach zero.  Now add in higher discharge rates and the knee moves from a lower SOC to a higher SOC.  One has to avoid the knee of the curve.   One can find discharge rate curves where the knee might be around 20%+ SOC.  Also, in Lithium Ion batteries the higher the discharge current, the lower the effective capacity (energy stored).  So, one needs to maintain enough energy stored in the battery and stay above the knee for emergency situations like WOT acceleration.    We hope Ford engineers designed the algorithms appropriately. :)

[fbov]

You know, the funny thing is that the battery is still subject to the laws of conservation of energy. So ultimately, all power is going to come from gasoline one way or another....

Exactly right, the game is all about what you do with that energy. This is how I think of it.

 

The first step is getting as much energy as possible out of the fuel. Look up "brake specific fuel economy" (BSFC) to learn about the factors that drive it. You can get a measure of how well you're doing, by calculating "ICE MPG."

ICE MPG = (total miles - EV miles)/fuel used.

 

In this case, the lower the better. I get down to 16.5 ICE MPG when I'm pushing 55-60 MPG, yet highway trips I'm usually in the 25 ICE MPG range, with mileage in the low 40's. This requires low speed, high load ICE operation, which is hard to do at speed.

 

Next is what you do with it. I include some numbers so you get a sense of scale. Yes, 10m in elevation is the same as going 30 MPH, so you can store 30MPH of kinetic energy by going up a 10m hill. You can't eliminate the parasitic losses, but you can minimize them (air pressure, Paul's grill block).

 

Then you play, taking energy out of the fuel tank, and putting it into elevation, battery charge, and the vehicle's speed. Store speed energy with regen, and use of hills. Release that energy, in concert with ICE/fuel, the road, and your driving preferences.

 

HAve fun,

Frank

Edited December 14, 2015 by fbov

[Taiwwa]

I just discovered today what the little button on the shifter does. Pretty nice when going down a long hill, of which there are a lot here in WV. It's like engine-braking on a stick shift, except you gain energy :) And you don't have to drive a stick which really sucks in stop and go traffic.