Normal degradation or problem?

[qflyer]

I have a 2014 FFE that I bought new. I've put 79,200 miles on it. My commute to work is 54 miles one way, and about 52 miles of the trip is interstate which I drive at 60-63 mph. During the summer I set the A/C to 68 degrees, and I would arrive at work with 20-25% charge remaining. Now that temps are in the 30-40 degree range, I have to stop at a L2 charger for about 20 minutes to make it with roughly a 5% reserve. I don't use heat, defrost, or any other environmental controls at all.

I've noticed that the charge goes from 100% to 70% within the first 10 miles of driving. The car is always plugged into a L2 charger, and I use preconditioning. If the charge dropped at that rate over the entire 100%, I'd only have about 35 miles range. Instead it's about 50 miles at 60-63 mph. So is that fast discharge of the first 30% just normal degradation, or is something wrong?

Today I went for a ride with the heat on, 60 mph, 38 degree air temp, and it dropped from 100% to 70% in the first 5 or 6 miles. The heat usage cycled between 3-5+ kwh for the entire 5-6 miles, but still, 30% used in 5-6 miles?

Hate to go through the hassle of taking it to a dealer (there's not one nearby) if they're just going to tell me it's normal, but I'll also be outside the warranty very soon, so.... If it were your car, and you saw what I describe, would you take it in or just accept it as normal degradation? Also, how would they diagnose a bad battery if that's what's actually going on?

Thanks

 

[jmueller065]

I would take it in on the off chance that you get a "free" larger battery. Its worth a shot.

 

[triangles]

Sounds pretty normal to me. Mine is also a '14 but I'm a bit behind at 21k miles. I occasionally have to make a trip to the airport which is about 55 miles from me. I have done it in the Teens F outside but I do some pretty extreme measures to make it there. I warm up the car in my heated garage, use no heat keep speed under 45mph for 3/8 of the way another 3/8 is 55mph and the remaining 1/4 is at 60mph. I get there with about 10-12% battery left. I would estimate my range with no heat in winter temps at 60-63mph to be about 45-50 miles.

Before you hassle with taking it to the dealer only to be told everything is normal, Check what your usable capacity is. Don't worry too much if it's low as it does go down when it's cold outside. It will increase when it warms back up in spring. You can use the enhanced trip meter to see how many kWh you've been thru once you get down to 5% or 10% from a full charge. From there you can do a little math to estimate how much you had if you were to run it to empty. For example say you used 15kWh to get down to 5% battery. Simply divide the amount used by the percent used; 15kWh/0.95= 15.8kWh usable capacity. I would guess you're somewhere about 15kWh usable. I have seen reports on higher mileage batteries down as low as 13kWh. Unfortunately Ford has no warranty on usable capacity. Also there usually isn't a problem with a battery that isn't throwing an error code unless it's usable capacity is significantly low. But like Jmueller065 said it can't hurt to have it checked before your warranty is up since if it is found bad you get an upgraded battery since the old battery is no longer available. Either way let us know how it works out.

 

[qflyer]

Results are in! It used 15.2 kWh from 100% down to shutoff at 0%. Outside air temp was 30 degrees F during the 2.5ish hours it took to run down to 0%. Sounds like the battery is definitely not "bad" per Ford's standards, but I may take it in anyways to take care of a couple recalls and see what they say about the battery.

I posted my 2 year, 40,000 mile review two years ago, and had decided that the car would not work for my wife's commute during the winter months within the next 1-2 years (it's now been 2 years). At the time, she was driving 50-55 miles round trip, using the heater all the time, and was getting home on cold days with just a few miles to spare. This all kind of confirms that, as I guessed two years ago, if she were still making that commute today, she wouldn't be able to use any heat, and even then, probably would not be able to make the round trip commute without charging along the way.

We've moved since then and she's started a new job that's a 70 mile round trip commute. Her employer lets her L1 charge, so range isn't a concern right now, but it will be in another 2 years if the battery keeps fading as it has been. By 120,000 miles, she'll have to stop using heat or just take the ICE car to work. I won't be able to use the FFE for my commute to work even in the warmer months by then, so we may have to move on from the FFE by winter of 2020. We'll see how things go, I guess.

Two years ago, I figured I'd lose money on the FFE compared to an ICE, mostly due to the poor resale value of the FFE vs an ICE. If I can make it to 120,000 I may actually break even or come out ahead.

Thanks for the advice, y'all. Your guess was spot on, triangles.

 

[triangles]

Some quick math says that you're at about 79% original capacity. However the cold in and of itself lowers battery capacity so you've probably got more like 85% of original capacity. So 15-20% degradation over 80k miles and 4 years seems about right. I wish our batteries were more like tesla where 10% degradation after 100k miles is the norm. Not sure if the Tesla battery is really that much better or if it's because a Tesla battery typically isn't cycled as much nor to the depth of discharge a typical FFE battery sees due to the Tesla battery's massive capacity.

A little side project you may be interested in that I probably won't get around to it until next fall assuming I ever find the time, I'm going to look at the possibility of shoehorning a diesel parking heater in place of the electric heater. I would run it on kerosene so it's exhaust wouldn't be as stinky as diesel since kerosene is more or less the same as diesel just more refined. If it's possible to make it work as a drop in replacement that would be awesome. That would lessen the range hit due to cold significantly!!! I don't really need the range with my whopping 15mi round-trip commute but it just seems a little crazy the range hit heat causes especially now that my FFE got booted out of the heated garage by my TM3.

 

[triangles]

FYI I checked my capacity today and my estimated number was 15.9kWh. This past summer it was a littler over 17kWh. I didn't draw the battery very low though it was at 36% when I back calculated so I don't have a lot of faith in that 15.9kWh being very accurate. If it is accurate it means the approx 60k additional miles you have is worth about 0.7kWh of degradation. I would be very happy if I only lose 0.7kWh over the next 60k miles but sadly battery age also adds to degradation. So I'll probably be way lower than that by the time I hit 80k miles.