Battery Degradation

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mikey7mc

Member
Joined
Jan 16, 2016
Messages
6
Location
Phoenix, AZ
Hello Everyone -

Hoping some experts on the Focus Electric can give me some advice.....I own a 2014 Focus Electric and have just hit 25,000 miles. In the past 2 months I have been dealing with noticeable battery degradation. I live in Phoenix, AZ and December and January have been unusually cool nights for this time of year, but I rarely use the heater (don't use the climate control at all most days in winter). My battery capacity has been topping out in the 60 to 65 mile range on a full charge. My daily commute is about 57 miles round trip and on days that I have not recharged mid-day, I'm making it home with about 8 miles of charge to spare.

What's odd to me is that even while driving down hill and doing as much coasting and braking as possible, I cannot get the combination of remaining miles plus miles driven back to 74 anymore. I have an appointment with my dealership service on the 26th of this month. Hoping they will have some answers for me, but looking for other owners who either have this problem or some advise for me.

Thanks!!!

Mike
Phoenix, AZ
 
How cold is unusually cold?

Even when not using heat you don't get as much out of the battery in the cold as you do in the summer. Remember the car is going to use some electricity to heat the battery and the batteries do have less capacity in the cold.

Your dealer will likely find nothing wrong.

Do you leave for work at the same time every day? Are you using the "go times" to get the car ready in the morning? If you aren't you should: Preconditioning the car saves a few wH and lets you get to work with a little more battery. In addition, setting a go time for 85F gets the car nice and toasty warm in the morning.
 
Thanks for the info Jmueller! Most days I do run the car while still plugged in before heading out. Unusually cold would be 37 to 40 degrees in the morning then temps in the 60's most of the day.

I do not remember this much of a decrease in overall capacity last winter.

Thanks again,

Mike
 
I started to notice battery fade around that mileage. It's likely to be real. When the weather warms up, it will improve, but there is a steady downward trend with time and miles.

My impression is that the reduction in capacity with age/miles is more noticeable when the battery is cold than when it's warm.
 
Your comments would seem to support what I am noticing Michael.

Prior to Christmas, when the weather was quite seasonal in Phoenix, I hadn't noticed much, if any, battery fade. It has really been the past 3 or 4 weeks that have been at the reduced 60 to 65 mile range.

I'll start being more diligent about pre-heating the vehicle while plugged in before leaving the house each morning. Maybe that will lessen the fade a bit. I'm still gonna have Ford run the diagnostic. Not expecting any help there though.

Anyone heard of Ford replacing cells like Nissan was doing with the Leaf a few years back?
 
The 'battery fade you are experiencing is caused by two things.
As temps drop internal resistance goes up and causes an effective temporary lower total available capacity.
The thermal management system triggers at 50F and will use its own power to keep internal battery temps up. That's why pre-heating is recommended as you at least start with a warmed battery.

Our thermal liquid cooling like volts and tesla's is far better for long term retention of capacity.

Cheers,
Chris
 
Thanks for all the helpful information! Sounds like I need to do a better job letting the liquid cooling and heating system do its thing for the good of the battery. I will report my wh/mi in the next couple days. Thanks again!
 
mikey7mc said:
In the past 2 months I have been dealing with noticeable battery degradation...My battery capacity has been topping out in the 60 to 65 mile range on a full charge.
The guess-o-meter is not an accurate measure of HVB capacity. You need something that can read the specs from the on-board computers for that. However, I don't doubt that you're experiencing capacity loss. Our FFE has only 20,000 miles and we're seeing significant capacity loss. This post contains a chart I posted fairly recently with our data.
 
In colder temps also be sure to check your tires air pressure.
Mine went down a lot in the winter - I checked it today and they were down in the low 30s compared to low 40s back in the summer.
So I added air to all the tires to get them up to 42-45psi for better efficiency again.
 
NightHawk said:
In colder temps also be sure to check your tires air pressure.
Mine went down a lot in the winter - I checked it today and they were down in the low 30s compared to low 40s back in the summer.
So I added air to all the tires to get them up to 42-45psi for better efficiency again.
Tire pressure usually drops about 1 PSI with every 10 degree Fahrenheit drop in temperature.
 
12v battery may be going south. It will suck extra juice from the big battery trying to keep it charged until it eventually fails. Rarely have had a 12V battery last more than a couple of years, even in my Escape hybrid.
 
Interesting, thanks for the information. Battery seems to be retaining its charge at a more normal level now that we are back to warm temps in Phoenix.

I'll continue to post updates here as I notice anything different as I'm now past 2 years of ownership.
 
coulomb_carl said:
12v battery may be going south. It will suck extra juice from the big battery trying to keep it charged until it eventually fails. Rarely have had a 12V battery last more than a couple of years, even in my Escape hybrid.

A way to help your batteries last longer is to buy a battery MINDer and put it on the charger for a minimum of 12 hours once per week. This is how I have my 2008 Sable with the original battery. This winter is the first winter I've ever had it not start. Took it out and swapped it with a yellow top I keep on the charger and left it on the minder for 2 weeks. Its as good as new again.

12v lead acid batteries really can last a long time if they stay out of the heat and are kept up! My boat batteries (4 lead acid) have a date code from 2003 on them. I had one go completely bad this past summer - first one. During the winter I take them out and put them on the minder and leave them on MINDers in the boat when not in use.
 
Lead acid batteries don't like 100 degee weather. They usally fail after 2 to 3 years. In cooler conditions they can last over 5 years.
 
jeffand said:
Lead acid batteries don't like 100 degee weather. They usally fail after 2 to 3 years. In cooler conditions they can last over 5 years.
I had a 2003 Saab that I bought in summer of 2010. It had the original Saab-branded 12V battery. It failed in August 2011 finally. That battery lasted 8 years!!
 
mikey7mc said:
Hello Everyone -

Hoping some experts on the Focus Electric can give me some advice.....I own a 2014 Focus Electric and have just hit 25,000 miles. In the past 2 months I have been dealing with noticeable battery degradation. I live in Phoenix, AZ and December and January have been unusually cool nights for this time of year, but I rarely use the heater (don't use the climate control at all most days in winter). My battery capacity has been topping out in the 60 to 65 mile range on a full charge. My daily commute is about 57 miles round trip and on days that I have not recharged mid-day, I'm making it home with about 8 miles of charge to spare.

What's odd to me is that even while driving down hill and doing as much coasting and braking as possible, I cannot get the combination of remaining miles plus miles driven back to 74 anymore. I have an appointment with my dealership service on the 26th of this month. Hoping they will have some answers for me, but looking for other owners who either have this problem or some advise for me.

Thanks!!!

Mike
Phoenix, AZ

There were some very good posts on this forum regarding how to check the battery capacity. Basically you fully charge the battery then you reset the trip meter so the kWh reading zeros out. Then you drain the battery completely until the green Ready-to-Drive icon turns off and read your current battery capacity as kWh on the trip meter.

You can drain your battery any way you like but you probably want to be siting next to a charger when the Ready-to-Drive icon goes off because the car is not going anywhere on its' own. Using the 6kW Defrost feature with the rear window defroster turned off will suck down the last few kWh quickly while the car is siting still. Most people are reporting capacity measurements in the middle 17 kWh range but some people are reporting as high as 19 kWh.

Last time I measured my battery capacity I only got a 16.7 kWh capacity measurement and I have just over 38,000 miles on my 2013 FFE. Which brings up some important questions, how bad does the battery need to be before a warranty replacement is justified or it's just time to replace the battery? The Ford warranty is petty vague on battery replacement and I generally assume that, if the battery still holds charge, Ford won't replace it.

I willing to accept a usable capacity of at least 9kWh, anything less than that and I'm going to be fighting Ford for a new battery if it's in warranty or finding a replacement battery if it's out of warranty. How bad would your battery have to be before you felt the battery needed to be replaced? Does anyone on this forum know Fords official battery replacement policy or do you know of any guidelines on when the electric vehicle batteries should be replaced?
 
Texas FFE said:
There were some very good posts on this forum regarding how to check the battery capacity. Basically you fully charge the battery then you reset the trip meter so the kWh reading zeros out. Then you drain the battery completely until the green Ready-to-Drive icon turns off and read your current battery capacity as kWh on the trip meter.

You can drain your battery any way you like but you probably want to be siting next to a charger when the Ready-to-Drive icon goes off because the car is not going anywhere on its' own. Using the 6kW Defrost feature with the rear window defroster turned off will suck down the last few kWh quickly while the car is siting still. Most people are reporting capacity measurements in the middle 17 kWh range but some people are reporting as high as 19 kWh.

Can we get someone with a brand new 2016 FFE perform this test so we can get a benchmark for degradation?
 
Texas FFE said:
Can we get someone with a brand new 2016 FFE perform this test so we can get a benchmark for degradation?

On another thread there was a discussion that only about 85% of the FFE battery is usable and there was one post of someone measuring 19.5 kWh which corresponds to the 23 kWh battery (.85*23=19.6). So after 3 years my FFE appears to be experiencing about 15% degradation ((19.5-16.7)/19.5). It looks like degradation levels off after about the first year so I don't expect my degradation to get much worse in the near future.
 
My 2016 FFE was doing 20.5kwh routinely when new (I liked to play until well pass the 0 mile indication)

today at 12,000miles (7 months) I am getting 19.9 ..not sure if because of very hot weather or just degradation. MY plan is to run as many miles (20k a year) on it before I get a Tesla X.


MY previous 2014 FFE at 11,000 miles had a hard time getting to 19...seems like the 2016 has better "software" as I routinely get 3-4 miles after the 0 mile left indicator....I don't think that was the case on '14
 
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