Sluggish acceleration

[cegarbage]

I'm only 350 miles into my car I just bought last week. Today I drove to work for the first time. I drove in EV mode and burned through the 19 miles by the time I got to work. The charging station was restricted and I couldn't get access to it to recharge.  As a result,  I drove home w/o the ability to be in EV mode.

 

To say the car was sluggish would be an understatement. The ride home was predominately uphill. I did something extreme on the way home, i went up the steepest street in LA (Baxter Street), similar to some of the steepest streets in SF. Then I went up a highway that has a gradual elevation. The car didn't want to go above 60 on the FWY unless I put my foot all the way down on the accelerator

 

I assumed once the 19 miles was used up, the car would operate like a regular hybrid. What am I missing?

 

 

[Rexracer]

It does continue to operate as a regular hybrid. A couple things you may not be thinking about. Since the car is designed to be as efficient as possible, the throttle mapping is programed to make you "want" to be efficient, i.e. it wants you to feel like you are pushing things to go fast, making you naturally drive more conservatively. Did you try putting your foot all the way down? Did it go?

 

The other things is this is a heavy car, 4k lbs, due to the large battery pack. The gas motor is making 141hp and the electric is 118, with a combined rating of 188hp. Thats 21.28lbs per hp, which is in no way sports car territory, but my suspicion is you burned through your battery reserve pushing up a hill, so you were down to 141hp, so 28.37lbs/hp, which is down right terrible.

 

If you had said "I do this drive every day and it was noticeably slower..." I would say "there is a problem, take it in". My suspicion is this just isn't what you are use to, and you need time to familiarize yourself with the car and its behavior. Its not a "normal" car, so it will feel/act differently.

 

Another suggestion, driving up the steepest hill you can find as quickly as you can, is NOT good for fuel economy, so don't do that. ;-)

[stevedebi]

I'm only 350 miles into my car I just bought last week. Today I drove to work for the first time. I drove in EV mode and burned through the 19 miles by the time I got to work. The charging station was restricted and I couldn't get access to it to recharge.  As a result,  I drove home w/o the ability to be in EV mode.

 

To say the car was sluggish would be an understatement. The ride home was predominately uphill. I did something extreme on the way home, i went up the steepest street in LA (Baxter Street), similar to some of the steepest streets in SF. Then I went up a highway that has a gradual elevation. The car didn't want to go above 60 on the FWY unless I put my foot all the way down on the accelerator

 

I assumed once the 19 miles was used up, the car would operate like a regular hybrid. What am I missing?

Hybrids are designed primarily to provide higher MPG in city driving. On the highway, they are less efficient. It has to recharge the battery every time it gets used up, which decreses MPG while charging, and (as formerly posted here), once that small amount of hybrid battery is used up, there is no extra acceleration available, and you are left with a pretty small engine. The impact of having to recharge the hybrid battery, plus the uphill, is going to reduce the power output even below what a conventional car would do in the same circumstances. Not to mention the extra 300 lbs or so of LiIon battery weight above a similar ICE only Fusion.

[cegarbage]

Thanks for the feedback. Is there any how-to manual on when it's ok to stay in battery only, when to set to auto, when to delay EV use? I assume it's ok to do battery only if going under 20 miles. I would think if you are taking a long trip that ends up in mountains maybe you'd want to delay burning through the electric charge. And all other scenarios in between.

[Rexracer]

There is a very detailed and exhaustive post about efficient driving here http://www.fordfusionenergiforum.com/topic/2566-efficient-ev-mode-driving-techniques/

but that gets pretty detailed and deep.

 

My basic rules:
- Minimize heat/ac. Now that its cold, if i turn on the heater my range goes down 30%.

- If I am going to be going on the freeway for more then 1 mile (and I will be doing city driving as well) I do EV later. The faster your going the faster you drain the battery. Save the EV for those times its most  efficient, stop and go traffic.

- Any hill that is very steep or very long I do EV later.

- Maximize your regen in braking (watch your braking scores to be sure you are doing Regen, not hydraulic brakes)

- Do not waste energy, be as conservative with accelerating as you can be (don't become a rolling speed bump though).

 

My goal is to be just finishing up all my EV power as I pull into my neighborhood, I can usually use the reserve power to get me to my house . Some days I have less driving to do, so I will just let it sit in AUTO and use the EV on hills and freeway. Sometimes I know I have a LOT of driving to do, so I do EV later (long trips, I save till I am in the city, or pulling on/off freeway).

Edited October 30, 2014 at 03:12 PM by Rexracer

[stevedebi]

Thanks for the feedback. Is there any how-to manual on when it's ok to stay in battery only, when to set to auto, when to delay EV use? I assume it's ok to do battery only if going under 20 miles. I would think if you are taking a long trip that ends up in mountains maybe you'd want to delay burning through the electric charge. And all other scenarios in between.

Well, it is "OK" to do any mode, any time you like. What you need to do is read up, and then try it out based on your commute. The car won't let you hurt the battery; only your MPG will tell what works for you.

 

My own technique is to switch to EV Later just before the freeway on-ramp, to allow the engine to begin warming up. It won't supply a lot of highway power until it is warm (thanks to Raja for pointing this out). But I also sometimes switch to Auto for a steep up hill, or even EV Now if I think I won't need the battery later.

 

My goal is to arrive home with almost zero battery left, and to stay in EV as much as possible.

[Gigi]

One might say that acceleration in the Energi is, shall we say, "deliberate."

 

After a long steep hill has depleted the battery, I imagine that the computer is thinking, "How much engine power can I give to keeping the car moving and how much can I give to charging the hybrid portion of the battery back to its nominal level?"  So long as a steady speed is being called for, it will balance the two as best as it can.  If you want to go faster and press the accelerator, it will rev the engine higher and use whatever is available in the battery to accelerate until the battery is tapped out and you have only engine power available.  Once the car settles into a steady speed, it will go back to matching the most economical engine speed with the demands for motion and charging.

 

My experience driving over mountain passes back East is that I have enough power to do what I want to do, but we're talking Appalachian Mountains here, not Rockies.