Technical question: Does hybrid system recharge even while driving?

[howardbc]

Hi. I am familiar with the process of braking regenerating the hybrid battery, but will just normal driving do it also? I was looking at the display that shows the whole car and noticed that it said something like "Hybrid battery recharging"  even while I was just driving the car - not coasting, not braking. This is after I had completely depleted the battery and am now in hybrid mode. The recharging words don't stay for long but it has me puzzled. It also says "EV Mode" for a short time too, occasionally, when I have depleted the batteries. 

 

Does this car actually recharge the battery even while driving? I have only had the car a week and am learning something new every day. I appreciate any knowledge you can send me. I am not an engineer but am interested in how things work - in simple terms. 

 

Thanks.

 

Bobbie

 

[murphy]

I can't speak to the Energi since mine hasn't arrived yet but my 2010 Fusion Hybrid charges the battery when going down hill in EV mode.  The charging provides the back pressure to keep the car from accelerating down the hill.  In a non-hybrid car the engine provides the back pressure.

[Brad Schuck]

I'm not sure which battery you are referring to. In hybrid mode mine does the same thing but it is charging the hybrid battery for the EV duty cycle of my driving. The manuals elude to charging the EV battery but so far once the EV battery has been depleted I've not seen it come back to life. That being said, while driving in in EV+ mode while braking I have seen the EV battery indicator go up, not the mileage, but the blue indicator. Not sure what it means. In my 2010 my hybrid battery never discharged while going downhill (down grade) when I would let the accelerator up just enough to "coast". My Energi seems to discharge whenever I have any accelerator at all. When I let off the gas entirely, it will start to charge, but it also slows down.

The dealer couldn't find anything with their diagnostics and I'm not sure anyone has any experience with the Energi yet. They reset my system. Some of the problems went away and some stayed but now I'm averaging around 83mpg on a 100 mile daily commute that includes leaving in the morning with a full charge, charging at work, driving to lunch on pure EV, and leaving work on a full charge. I'm ecstatic with the improvement.

[Brad Schuck]

I can't speak to the Energi since mine hasn't arrived yet but my 2010 Fusion Hybrid charges the battery when going down hill in EV mode.  The charging provides the back pressure to keep the car from accelerating down the hill.  In a non-hybrid car the engine provides the back pressure.

The Energi is completley different from the 2010. I had the fully loaded 2010 Sterling Gray and I averaged 45mpg over 20,000 miles. I loved it. The Energi tests your skills if you drive over 15 or 20 miles at a time but it is a great car. Definitely don't expect more than 50mpg on a long drive and 43mpg if you drive above 62mph. We had some problems at first but the car is turning out to be exactly what I wanted. Don't expect any great service relating to the vehicle yet as I think the Ford dealers are as much in the dark as we are. It will get there I'm sure.

[Energized]

Hi. I am familiar with the process of braking regenerating the hybrid battery, but will just normal driving do it also? I was looking at the display that shows the whole car and noticed that it said something like "Hybrid battery recharging"  even while I was just driving the car - not coasting, not braking. This is after I had completely depleted the battery and am now in hybrid mode. The recharging words don't stay for long but it has me puzzled. It also says "EV Mode" for a short time too, occasionally, when I have depleted the batteries. 

 

Does this car actually recharge the battery even while driving? I have only had the car a week and am learning something new every day. I appreciate any knowledge you can send me. I am not an engineer but am interested in how things work - in simple terms. 

 

Thanks.

 

Bobbie

 

Does this car actually recharge the battery even while driving?  

 

Yes, the engine will charge as least the smaller of the two HV batteries.  I don't believe it charges the bigger battery.  

 

The Ford website says:

 

Battery charged by: The gas engine, recycled energy from braking and by plugging into a 120-volt outlet or 240-volt outlet upgraded with electric vehicle supply equipment

 

You can watch this engine charging on the pictorial screen by watching the white line move from the fuel tank to the engine and the blue line move from the motor back to the battery. 

 

In this state the engine is providing power to move the vehicle, in addition to providing power back into the battery for later use.  That stored energy is used to propel the vehicle when the engine turns off and the car is operating in hybrid EV mode.   This is very common at speeds up to the mid 60s but I've actually seen it at higher speeds than that.  This extends the time the vehicle is operating in EV mode.

 

As for regeneration, there are actually two methods of regeneration.

 

One method is via braking which everyone is familiar with, and the second method is via throttle-off regeneration which mimics engine compression (even though the engine is not on).  

 

For trivia sake, this approach to regen differs from the Telsa Model S which only uses an extreme version of throttle-off regen since it does not have regen operated by the braking system.  In the Telsa, simply releasing the accelerator is like stepping on the brake.  The braking effect is so large that the car will actually illuminate the brake lights in some conditions.  The sensation is sort of like driving a toy car at an amusement park.......lift off the throttle, the car stops. 

 

The Energi's dual approach to regen is a much more elegant solution in my opinion and has a much more natural feeling.

Edited April 13, 2013 at 07:15 PM by Energized

[apm]

Based on the experience with the 2010 Fusion Hybrid, the battery cannot go below a certain level because all the electric components, such as AC, break pump, etc. have to operate at all times. Theses systems are normally operated by the belt system on a normal car, but on a Hybrid because they have operate while the engine is off, they all have to be electric. If the hybrid battery drops below a certain level, then engine will turn on to recharge the battery to the minimum level required.

 

I have to assume that the Energi works in the same fashion.

 

Regards,
APM

[larryh]

There is an interesting document at http://www.motorcraftservice.com/vdirs/diagnostics/pdf/OBDSM1302_HEV.pdf that describes the modes of operation of Ford's hybrids and plug-in hybrids:

 

Look at the section entitled Propulsion Modes.  It describes four modes of operation:

 

Series Mode:  car is not moving and the engine is running to power the generator to charge the battery, heat the passenger compartment, or catalyst warm up.

Postive Split Mode:  engine is running to power the generator (to charge the battery) and for propulsion.  The electric motor makes up the difference if the engine does provide enough or provides too much power.  It seems the electric motor can also act as a generator (consuming power). 

Negative Split Mode:  the engine is on and the generator consumes power to reduce engine speed (when the battery is fully charged).

Electric Mode:  the engine is off and the electric motor provides propulsion.  Note the engine cannot provide reverse torque--so the electric motor is used for reverse.

 

Larry

Edited April 15, 2013 at 09:20 PM by larryh

[bibolton]

Yes the Fusion Energi will charge the HV battery while driving but usually not enough to put, or show miles back on your battery display. I have been able to charge mine to 2 miles using the "hill assist" button on the gear shift and going down a fairly good down grade. Even though your brakes will regenerate power while going down hill, it is nothing compaired with "hill assist"

Edited April 23, 2013 at 01:31 PM by bibolton

[howardbc]

Hi, bibolton. I don't see a button that says "Hill Assist." Where is it? It sounds like it may be similar to the "B" button on a Prius that is only used when one is going downhill for some time. It's very flat where I live but am curious where the "Hill Assist" button is. Thanks.

[rprobst]

It's on the shifter. It's a little metal button on the left of it. No label on the button, and as far as I can tell, no indicator in the dash of when you have pressed it, but you can feel the difference when the button is in or out. And you can feel the difference in the car's motion while coasting.

[47Minutes]

There is a dash board indicator when I've had mine enabled.  It is yellow and of a car outline on top of a left descending grade.  Located on the bottom of the left hand display.