Regenerative Braking System & Coasting

[neod192]

Most of the time I use the brakes I don't come to a full stop, so I can't see the brake score. Am I correct in assuming that I'm still recovering energy even if I don't come to a full stop? I think that's actually better, because you don't have to get the car moving from a full stop, thus using even more energy that you gain by stopping all the way.

 

I'm starting to doubt this because the battery doesn't seem to really charge from the regen bakes when I do this and my Regen miles are pretty low. Please tell me I'm not insane ! :) I've seen decent recharges when I get off the highway (60 mph) and come to a complete stop - it charges about 1/4 of the battery.

 

I'm also letting go of the gas pedal and coats to a light, and only use the brakes for the last portion of the trip, so I don't get a lot of use out of the regen brakes - the car seems to want to stop on its own! I can't estimate distances very well, so can't say how quickly it slows down, but it's definitely faster than my manual Gti. My wife noticed this too - it doesn't coast as far as a gas car does.

[acdii]

The car charges when you lift your foot completely off the gas, but charges much quicker if you apply light pressure instead of coasting. This took the longest for me to get used to compared to the old Hybrid. Instead of coasting, use the brake, you will find that its not much different. Also what it does not like is firmer pressure towards the end of the stop, it takes a bit to get the feel of when its is regen, or hydraulic. it is a totally different animal compared the the first gen Fusion and the Toyota HSD in how it works. It has much more emphasis on using the regen braking than the others.

[neod192]

Thanks, it's my first Hybrid so at least I don't have to adjust to it from another hybrid :) I do have to adjust from driving a manual Gti...

[acdii]

It took me a few months when I got my first Hybrid, a Prius, before I started to get good MPG in it, the good part is that it transfers easier into a non Hybrid once you get the hang of it.

[fusionTX]

Thanks, it's my first Hybrid so at least I don't have to adjust to it from another hybrid :) I do have to adjust from driving a manual Gti...

These cars do not coast well at all. I noticed this on my second test drive and can reconfirm it now. They slow down very fast. I imagine this was a deliberate design decision, but one I do not particularly like, as coasting to a light is an easy way to save gas. Coasting is one of the easiest techniques to increase mileage in a hybrid, but that option has been greatly reduced with the 2013 Fusion Hybrid.

[acdii]

Looks like Ford is trying to capture as much regen as possible in these.

[corncobs]

The coasting question has come up again and again why not run a little test.

 

Lets say on a level stretch of road go 40 mph and record the speed after 0.1 miles after starting to coast. Or set the cruise to 40 and hit cancel and record the speed after time x (10 sec, 20 sec).

We probably all have some kinda GPS device which allows for a bit more accurate results. Obviously we have take the wheels into consideration and also weather conditions and wind. But if we take samples over a few days those differences shoul even out.

 

I think that should provide some good data points for comparison between coasting deceleration.

I'm gonna do this on my way home this afternoon and report back the first round of results.

Edited April 15, 2013 by corncobs

[acdii]

You can if you want, but I did a better test. I had my wife follow me in the 10. She had to ride the brakes every time I took my foot off the gas to keep from running into me. Thats how much it slowed down. The only time it didnt slow like that and coasted like the 10 was when the battery was fully charged, then it rolled nicely.

[corncobs]

OK I will keep an eye on the battery as well. But I remember that test and honestly if I take my foot of the gas it doesn't feel like such a sharp deceleration that people behind me would need their brakes.

 

Lets see what happens on the way home it's gonna be interesting.

[acdii]

OK I will keep an eye on the battery as well. But I remember that test and honestly if I take my foot of the gas it doesn't feel like such a sharp deceleration that people behind me would need their brakes.

 

Lets see what happens on the way home it's gonna be interesting.

I heard the same, its hit or miss it seems, some cars do, some don't. I guess it depends on what you are used to driving too.

[fusionTX]

You can if you want, but I did a better test. I had my wife follow me in the 10. She had to ride the brakes every time I took my foot off the gas to keep from running into me. Thats how much it slowed down. The only time it didnt slow like that and coasted like the 10 was when the battery was fully charged, then it rolled nicely.

 

That is exactly right. If the battery is charged to a certain level (over half for sure, maybe three fourths), then the car will coast with no resistance.

[corncobs]

That is exactly right. If the battery is charged to a certain level (over half for sure, maybe three fourths), then the car will coast with no resistance.

 

Here is what I did figure out today; I paid attention to the charging level of the battery and the coasting performance and yes as already stated by acdii and fusionTX there is a definite difference with a lower SOC and a more aggressive recharging.

The one test I did do was on the interstate just after getting on with about ½ charge it came out to be about 5 mph in 6 seconds canceling the CC at 65 mph. Another test with the same 65 mph start point down to 55 mph in about 11 seconds.

 

I will keep an eye on this topic and report back after some nicer weather and more test cycles.

[hybridbear]

Most of the time I use the brakes I don't come to a full stop, so I can't see the brake score. Am I correct in assuming that I'm still recovering energy even if I don't come to a full stop? I think that's actually better, because you don't have to get the car moving from a full stop, thus using even more energy that you gain by stopping all the way.

 

I'm starting to doubt this because the battery doesn't seem to really charge from the regen bakes when I do this and my Regen miles are pretty low. Please tell me I'm not insane ! :) I've seen decent recharges when I get off the highway (60 mph) and come to a complete stop - it charges about 1/4 of the battery.

 

I'm also letting go of the gas pedal and coats to a light, and only use the brakes for the last portion of the trip, so I don't get a lot of use out of the regen brakes - the car seems to want to stop on its own! I can't estimate distances very well, so can't say how quickly it slows down, but it's definitely faster than my manual Gti. My wife noticed this too - it doesn't coast as far as a gas car does.

 

Below a certain speed (around 5 MPH it seems) the regen braking stops and the car just uses the friction brakes. So rolling through a stop shouldn't cost you much in the way of regen braking. At those low speeds there is also minimal energy to be regained because the wheel are not rotating very quickly and thus are rotating the electric motor much more slowly to regenerate electricity.

 

How is your brake score? How does your braking bar look on the coach screen?

[neod192]

 

How is your brake score? How does your braking bar look on the coach screen?

Thanks! My brake score is around 98% and I'll have to check the braking bar after I get my car back from the bodyshop :(. That bar only shows recent driving, so it might not be a good representation of driving style over a long period of time.

[hybridbear]

Thanks! My brake score is around 98% and I'll have to check the braking bar after I get my car back from the bodyshop :(. That bar only shows recent driving, so it might not be a good representation of driving style over a long period of time.

 

Why is your car in the shop? It's true the bar is only recent but it can be helpful if you check right after you've done some of those stops to see what it reflects.

 

I'm very careful to make sure I fully stop for stop signs because we live in a low crime part of the city so the Police have nothing better to do than watch for people rolling through stop signs or going 5 MPH over the speed limit. On my short drive to work there are 2 different stop signs where I've seen them sitting off to the side hiding waiting for someone to roll through the stop sign. So I'm very careful to fully stop.

[neod192]

 

Why is your car in the shop?

http://fordfusionhybridforum.com/topic/6441-cracked-chipping-paint/

 

I don't roll through stop signs (already got a ticket for that, so no more!), but will roll through right turns w/ green lights or try and time the lights so that I don't have to fully stop.

Edited April 16, 2013 by neod192

[acdii]

I do that too. Watched a Special kind of Stupid in a pickup today blow past me, then I rolled through the next green light that he was stopped at when red.

[B25Nut]

Rolling stops? I call them green stops. They're good for the environment, you know....

 

The best explaination I've heard was by a policeman that was ticketing someone for a rolling stop. When questioned about what difference it makes, the cop said that if he was hitting the driver with a billy club and he asked him to stop, would the driver want him to just slow down the pace of the beating?

 

Rolling stops also make me a safer driver by being fully aware of my surroundings.

[hybridbear]

I don't roll through stop signs (already got a ticket for that, so no more!), but will roll through right turns w/ green lights or try and time the lights so that I don't have to fully stop.

It makes perfect sense to avoid fully stopping when legally possible and when it is safe to do so

 

Rolling stops? I call them green stops. They're good for the environment, you know....

 

The best explanation I've heard was by a policeman that was ticketing someone for a rolling stop. When questioned about what difference it makes, the cop said that if he was hitting the driver with a billy club and he asked him to stop, would the driver want him to just slow down the pace of the beating?

 

Rolling stops also make me a safer driver by being fully aware of my surroundings.

Hahaha that's a great explanation

[acdii]

Stops? We no need no stinkin stops? Floor it muchachos!

[fusionTX]

I wonder why, when coasting, the graphics do not show the battery charging. Seems like an omission.

Do older Fusion models show this?

[neod192]

I wonder why, when coasting, the graphics do not show the battery charging. Seems like an omission.

 

Do older Fusion models show this?

Every once in a while I see the up arrow if I let go of the gas pedal and I'm going downhill. If I'm on a flat road, I don't see the up arrow and I'm assuming it's not actually charging.

[aaronj1159]

Every once in a while I see the up arrow if I let go of the gas pedal and I'm going downhill. If I'm on a flat road, I don't see the up arrow and I'm assuming it's not actually charging.

Interesting. Pretty much anytime I let off the accelerator completely I'm seeing an up arrow.

[acdii]

 

Do older Fusion models show this?

Yep! any time a reverse power application happens, braking, coasting, going downhill, accelerating when cold, my battery shows a charge in the 10.

[fusionTX]

Interesting. Pretty much anytime I let off the accelerator completely I'm seeing an up arrow.

Coming home from work today, I noticed there is an up arrow when coasting. My bad.