Decreasing Range

What is an acceptable amount of decreased range? I took delivery of a new FFE at the end of April of this year. Initially, it would show a range of anywhere from 70-80 miles, when fully charged. When I fully charge it now, I get a range of about 50-58 miles. I know batteries degrade over time, but is this typical or acceptable? I've driven a total of about 5,400 miles so far.

It isn't degrading, its simply the weather and your usage.

The range displayed is simply a guess by the car's software based on your most recent driving pattern/power usage (there is a reason the range display is called the Guess-O-Meter).

Are you using the heater a lot driving around?

jmueller065 said:

It isn't degrading, its simply the weather and your usage.

The range displayed is simply a guess by the car's software based on your most recent driving pattern/power usage (there is a reason the range display is called the Guess-O-Meter).

Are you using the heater a lot driving around?

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I didn't think it would matter when it was initially turned on fully charged still sitting in our garage. I just tried turned it on and turned all the heating off. I gained 10 miles on the range. So it's not as bad, but is still off about 15%.

wressler said:

I didn't think it would matter when it was initially turned on fully charged still sitting in our garage.

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It still uses how you drove yesterday as an approximate to today. Thus even after fully charged the range displayed can be wildly different than it was yesterday.
If you only drive 25 mph all day your morning's range will be 100+ (especially if its summer) the next day. Then if you drive the highway all day your next mornings range will be around 70.

Drive with the heater blasting and the next charge will show a good 10-20 miles shorter at full than the previous one.

In any case, the estimated range is NEVER an indicator of battery capacity. It is mainly an indicator of YOUR driving style and energy usage (including accessories, such as the heater).

The only indicator of battery capacity is the kWh that can be consumed after it has been fully charged, and even that will vary with other factors, including the temperature during charging and consumption. Generally, capacity will decrease with colder temperatures and increase with warmer.

WattsUp said:

In any case, the estimated range is NEVER an indicator of battery capacity. It is mainly an indicator of YOUR driving style and energy usage (including accessories, such as the heater).

The only indicator of battery capacity is the kWh that can be consumed after it has been fully charged, and even that will vary with other factors, including the temperature during charging and consumption. Generally, capacity will decrease with colder temperatures and increase with warmer.

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+1 very well said!
Ford has published a Special Service Message (SSM) about this: http://www.myfocuselectric.com/forum/viewtopic.php?f=15&t=2921&hilit=ssm#p21420

SSM 44918 - 2012-2015 Focus Electric, 2013-2015 C-Max Energi, 2013-2015 Fusion Energi - EV Range Display Variance After Charging (Effective Jan 30 2015)
The EV Range being displayed after fully charging a 2012-2015 Focus Electric, 2013-2015 C-Max Energi or 2013-2015 Fusion Energi may vary after each charging event. A variation of EV range does not indicate a battery or charging concern. EV range is similar to the Distance To Empty indication on a gasoline vehicle and the EV range will vary with vehicle operating conditions. Conditions that impact EV driving range include: cooler outside temperature, terrain, driving style, city or highway driving, tire pressure, and use of accessories. Using the cabin heater and A/C, which are electric, will also decrease EV range. To temporarily remove the impact of driving/climate history, reset the Lifetime Summary or Driving History by using the Settings menu on the left side of the instrument cluster, under Display.

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hybridbear said:

To temporarily remove the impact of driving/climate history, reset the Lifetime Summary or Driving History by using the Settings menu on the left side of the instrument cluster, under Display

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Has anyone ever tried this procedure? Anything interesting to report?

You can calculate the usable capacity of the Focus electric battery pretty easy.

When you take a long trip (30-40miles+)reset one of the trip minders in the beginning of the trip and also note the battery percentage.

When you are finished the note the KWH used on the trip and the end battery percentage.

Usable Capacity = KWH/(begin battery %- end battery %).

Example = 9.0KWH /(.75-.25)= 18KWH.

It should be about 18 KWH. Just need to do over a fairly large amount of battery usage to take out non linearities.

The mileage GOM (Guess o meter) has nothing to do with battery capacity.

This approach works quite well, but I would run the battery down a bit (maybe to 90%?) before starting the test because the percentage falls excessively in the first few miles and will give a misleadingly low estimate of battery capacity. In other words, don't start the test from a full charge.

If possible to run the test between maybe 90% and 10% or so, this would be pretty good. the 75%/25% example noted able is also OK, but a little wider might be better.

If you have Forscan or a Scan Gauge, another way is to start the test from fully charged and reset the trip meter. Run the car down pretty far and add the kWh used to the ETE.

Example: 16 kWh used on trip meter, 2 kWh ETE, total capacity 18 kWh.

In my experience the ETE shown after a charge is not accurate and overestimates the available capacity.

My favorite way is to charge the battery, reset the trip meter, open the windows and run the heater full blast. In about three hours the battery will run down and the usable capacity will be displayed.

Didn't see anything relating to resurrection of older threads n the FAQ, so I figured I'd add something to this.

Ideally the battery percentage displayed should map in a linear manner to the actual remaining capacity/SOC, but for my used FFE it seems to only align at 100%, 0% and around 60%-65% - underestimating remaining capacity at the beginning of discharge and overestimating it under 60%. It almost seems like it's using the "new" battery parameters to estimate SOC instead of updating them as it ages.

Short of getting the ETE with the scanner (which may not be correct if the monitor isn't actually updating the battery parameters) the most reliable way to determine would be a full charge/discharge cycle with a reset trip meter (or viewing the full 'trip' summary when shutting it down) instead of partial extrapolation.

The heater method seems a good way to run it down in a controlled manner - the biggest variance would be battery temp at that point. You can also make note of what kWh values correspond to which percentages for SOC so you have a better idea of when the SOC reading is mis-aligned and by how much.