hest_c
Posts: 2
Joined: Sat Dec 15, 2018 9:31 pm

battery Degradation over 5 years?

Sat Dec 15, 2018 9:42 pm

Hi everyone, just bought my first FFE (and first electric) today, 2013 with 47k on the odometer. When I got to the dealership to test drive it was at about 80% ish battery and showed a range in the 40+ so I wasn't concerned. However on my 30 mile trip home afterwards the range dropped severely to 12 miles left by the time I got home and battery percentage seemed to drop precipitously as well. Since this is my first electric and FFE I wasn't sure if this was normal for a 5 year old 47k mileage car? It was cooler today here in CO so the HVAC was on and off on the drive but not cranked.

I have 4 more days where I can return the car for a full refund if I'm not happy, just wondering if this is exceptional degradation and should be taken up with FoMoCo and/or dealer or if I should just take the car back and keep searching or if this is normal or it wasn't fully charged?

amped
Posts: 60
Joined: Thu Aug 11, 2016 3:31 pm

Re: battery Degradation over 5 years?

Sun Dec 16, 2018 1:15 pm

Some more info would be useful. What was the ambient temperature like? What kind of driving (slow/urban; fast/hwy) was done during the 30 mile trip? Was the ~40 mile range estimate with climate control on or off? OEM tires?

Off the top of my head, for a car that was probably being driven aggressively by prospective buyers, I'd say that 40-ish miles on the guessometer with the cabin heater on and ~80% battery SOC is not that far off the mark. You say you started with >40 miles estimated range, drove 30 miles, and ended up with 12 miles left. That seems like exactly what one would expect. Why do you call it a severe drop? If you search the forum you can find info on doing a battery draw-down test. Bear in mind that colder battery temps during winter will reduce the effective battery capacity.

For my lightly used 2014 FFE (~30,000 miles), during the current winter season (mild Gulf Coast weather), I typically see 60-65 miles on the guessometer when fully charged and the heater is off. This is with non-OEM tires (better wet traction but higher rolling resistance) that reduce my range a bit. In summer, it's usually ~90-92 miles with no AC ( was typically 94+ with the OEM tires) - however, I do a higher proportion of slow urban driving in summer, which probably exaggerates the winter/summer differences.

hest_c
Posts: 2
Joined: Sat Dec 15, 2018 9:31 pm

Re: battery Degradation over 5 years?

Sun Dec 16, 2018 3:47 pm

Thanks Amped, I was wondering how accurate the estimated mileage was, and a little more reading I found that the guess-o-meter is exactly that and I didn't look at the percent of the charge. I'll definitely be doing a draw down test in the next few days while I have the opportunity to drive it to work and back, hopefully that'll help ease my concern about the purchase. Love the car overall but wanted to be certain I wasn't buying in to something that would not be viable for my 32 mile round trip commute!

triangles
Posts: 1051
Joined: Tue Aug 16, 2011 11:40 am
Location: Toledo, Ohio

Re: battery Degradation over 5 years?

Mon Dec 17, 2018 10:39 am

look here for how to turn on enhanced tripmeter: http://www.myfocuselectric.com/forum/vi ... 931#p30931
There's also good information here: http://www.myfocuselectric.com/forum/vi ... =14&t=4534

Long story short you should have in the neighborhood of 15kWh usable battery. The above link shows how to calculate that without running the battery flat. FYI if you didn't already know the more you run the battery completely flat the quicker you accelerate battery degradation. Winter range with moderate heat usage is about 40mi and summer range should get about 70-75miles. Ignore the guess-o-meter untill it's very low as it is often wildly inaccurate for the top half of the battery. The big thing is to keep your speed down. EVs are the exact opposite as ICE cars. They are very efficient in city driving and range will take a huge hit at freeway speeds. If your commute is all freeway you may be pushing it to do RT 32miles using the heat. 45mph and under is where you will get the best range. I once attempted a long distance freeway trip at the end of December in northern Ohio using no heat. I had to slow down to 50mph in order to make the 63 miles to the next charge stop. Not a safe thing to do on a 70mph freeway but I had no choice. Thankfully traffic was somewhat light. I am certain 4 years later I would not be able to make that trip again. You mentioned you're in CO so hill climbing will reduce your range a little too. The bonus is you can recoup about 80% in regen going down the hill. Oh another thing that may not be intuitive. Your battery capacity will go up a kWh or two in summer. It's a double whammy, not only does the cold require you to use more energy but it also temporarily reduces the capacity of your battery pack.
2014 Blue Candy FFE
http://www.fuelly.com/car/ford/focus/2014/triangles/303811 (since this forum doesn't allow BBcode in sigs)

triangles
Posts: 1051
Joined: Tue Aug 16, 2011 11:40 am
Location: Toledo, Ohio

Re: battery Degradation over 5 years?

Mon Dec 17, 2018 10:43 am

I should also mention you can easily do a 50+mi trip in cold winter but you have to take extreme measures like using no heat and preheating the car/battery ahead of time. I have a heated garage so I just heat the whole car up. Also another winter tip to avoid necessary heat usage (FYI defrost runs both heat and AC!!) is to crack one or both of your passenger windows. It can almost eliminate the need to use defrost to clear the fog from the windows. Oh yeah, welcome to the FFE club!

edit: I just did a quick calculation, you can see what your average Wh/mi is and use that and your estimated battery capacity to see if your 32 mile commute is feasible. ie 15kWh/32mi=.46875kWh/mi or 469Wh/mi. That would be pretty extreme. My average winter consumption is about 350Wh/mi although in really inclement weather I have flirted with 400Wh/mi. I have a 15mi round trip commute so I generally don't conserve too much. Hope this helps you figure out if the FFE will work for you or not.
2014 Blue Candy FFE
http://www.fuelly.com/car/ford/focus/2014/triangles/303811 (since this forum doesn't allow BBcode in sigs)

Phoenix
Posts: 3
Joined: Mon Dec 17, 2018 1:30 pm

Re: battery Degradation over 5 years?

Tue Dec 18, 2018 8:50 am

I have had my FFE for six years now and put less than 45,000 miles on it. In general, when it was new it would show 78 miles of range when fully charged, then after six years and 45k miles in general it would show 68 miles of range at full charge. So anecdotally, I lost almost 13% of my range over that time.

Phoenix

Return to “Batteries and Charging Forum”