Optimal charging to enhance the longevity of the battery

[pwebb]

Hello I am a new FFE owner as of Dec17 2013.
I have learned a lot about the EV already.
My goal is to maintain the battery as best I can. I have my car in my uninsulated garage. I live in Colorado so it can get quite cold. As recommended by. Ford I do plug it when it is cold usually with my 120 outlet. If I can not charge it fast enough I will use my 240 outlet. I have read its better to slow vs a fast charge. Is this correct? I plan on insulating my garage. I charge to full as I have read its not truly 100%. At work I park in a underground parking garage that is cold in the winter and cool in the summer. I have read it is better for the battery if I do more shallow charges vs deep charges. Even though I don't need to recharge at work as my round trip commute is 48 miles I do for this reason.
I am concerned about the summer as my garage can reach 98 degrees in the summer. I am going to insulate this spring. Does anyone know how warm is too warm?

Well I will end by saying I love the car so far, it drives great. I love the instant torque when needed. I have quickly learned that driving habits have a big impact. Any help is gladly appreciated thanks

 

[jmueller065]

Search around here, there is a lot of discussions along these lines.

 

[v_traveller]

Congrats on your new FFE, pwebb! Here's my $0.02, but I suspect you may have read many of the links already, sounds like you did a lot of homework:

http://vinn.myevblog.com/2013/10/12/prolonging-life/

Re: Slow charge vs. fast charge - consensus seems to be that quick charge is discouraged (not a concern for current FFEs, obviously). No issues with L2 vs. L1 charging have been published; in my experience seems like the FFE thermal management system works hard at keeping the battery temp down while pushing that last kWh when near full charge.

WattsUp has a great write-up on deriving the likely upper and lower margins of the FFE's battery, but I can't seem to find it very quickly... WattsUp, can you help?

As far as how warm is too warm - I park my FFE outside and it's gotten to 105F this past summer, got the "too hot" message twice. From what I read, the battery's heat tolerance seems to be related to the state of charge. To deal with this, I keep the state of charge at less than 85% unless I know I'll be driving somewhere immediately after unplugging. And if the ambient is over 102F and state of charge is more than 50%, I'll remote start the FFE in the afternoon. Ever since doing so I've never gotten a message from the FFE to plug it in because it's too hot.

I suspect that since your FFE will be in a garage sheltered from the sun, even at 98F you may not have a problem like I do. Alternatively, I think you can just keep it plugged in on hot days while it's in the garage so that the thermal management system can do its thing... others on the forum can probably speak to that.

 

[WattsUp]

WattsUp has a great write-up on deriving the likely upper and lower margins of the FFE's battery, but I can't seem to find it very quickly... WattsUp, can you help?

Thanks v_traveller.

I think I've probably written it up more than once here, but here's one occurrence that I found:
http://www.myfocuselectric.com/forum/viewtopic.php?f=8&t=1379&hilit=usable

The sixth posting in the thread, from Sun Oct 06, 2013 11:18 am.

 

[michael]

As best as I can determine, Level 2 charging is much preferred. There is so little power available on Level 1 that it appears that the thermal management system doesn't kick in. You will note that Ford describes the 110 V EVSE as a "convenience charging cord".

With regard to "what's too hot?"....when the ambient temperature exceeds 100 F, the car shows a message stating that it's hot outside...plug in when not using the car. I would say that the closer to room temperature or slightly below, the better.

I have wondered whether 3 KW level 2 charging is better for the battery than 6 KW, and the consensus seems to be no big difference. Nonetheless, I do use 3 KW at work whenever possible in preference to 6 KW. The main reason is that with 6 KW, you will charge up in a few hours, and in a shared charger situation (like I have at work) you need to disconnect and allow other to charge. By using a portable 3 KW charger, I occupy only a 220 outlet and use my own portable, so I can stay hooked up all day without interfering with others.

At risk of re-igniting an old controversy, it's still my opinion that for optimum battery life you should terminate charging before reaching full charge if you don't need full charge. Others here have disagreed. I run my battery between 80% and 20% for my daily commute, rather than between 100% and 40%. Look into the published reports, see if you agree with me or not.

PM me if you want further information.

 

[az erik]

I see alot of these types of posts and would like to pose a question, in no way is this meant to sound rude or harsh.

Are you planning on keeping your FFE past 3 years? (normal lease terms and what the majority of people got these cars for)

Lets figure even if we are 'kind' to the battery and follow all the directions, I'm replacing my FFE at the end of my lease. Either with another or a Tesla. EV's are like cell phones really. Battery tech and other tech continues to improve, leaps an bounds every couple years. 3 years from now if a replacement battery comes out that doubles the range for 1/2 the price of a new battery would you care that you kept up your battery as much as possible? As far as a lease goes I have not seen a single EV lease that states the battery must perform X good in X months. They are covered by a 6 or 8 year warranty to 80% capacity. If they don't do at least that the battery is poor and will/should be replaced anyway.

I say the above based on my thoughts. I have leased my FFE for 3 years knowing there will be improvements as the FFE will be 6 years in the field at that point. The extra conditioning is nice, if you were to own the car and planned on keeping it for max resale value 6+ years from now. However in my case I can't plug the car in at work to make the battery cooler or warmer, only at home. So I figure I'll be doing 1/4 the amount of "It's hot/cold plug me in" over the next 3 years. I know it sounds like I could care less about the future owner of this FFE but truth be I care more about my hassle. As the residual on to be paid off at the end of my 3 year lease is $28k it makes no sense to keep the car.

Now if I was shopping for a used FFE the tables turn but there is so far no way to get much of a life history of the car before you buy it. Things might change. I don't think anyone really has the inside on what Ford, Nissan etc plan is with used EV's at this point. Heck even my HV's battery is questionable at most and I can't get Lexus to give me a battery report on it.

Also keep in mind the conditioning happens the whole time you are driving it as well, which does help over the Leaf's shortcomings, at least in PHX when it's 115 outside.

As best as I can determine, Level 2 charging is much preferred. There is so little power available on Level 1 that it appears that the thermal management system doesn't kick in.

My cooling management does work on 120v, it's possible the heating doesn't. The first night I got my FFE the fans "were a blazin" in my 105 degree garage while charging. I couldn't tell you if the management works when not charging but still plugged in.

 

[pwebb]

Thanks for the replies everyone. I spoke with the so called FFE "expert" at the dealerhip where I bought the car and he did'nt have a clue to my questions. As well as most of us have noticed there is little helpful information in the owner manuel. I have a email out to Ford company tech, hopefully someone will know.

I agree with the last reply that if you are leasing the FFE, you may have less to be concerned about the battery. I can't say I agree that there will a big improvement in the battery tech in 5 - 6 years though. I think the big push is just to be able to get the cost down, as well the 76 mild range meets my needs, I don't need it go 150 miles or whatever and if the battery is still good at 5 years whats the point of replacing the battery with better tech even if is cheaper, it still costs.

 

[michael]

I'm leasing the car, but I have 19.5K miles/year, so at the end of three years the car will have well over 50K miles on it. I'm not worried about how good the battery is for the next owner...I'm worried about having as close as possible to the original capability three years down the line. The Leaf drivers are getting hurt badly on this in some cases...I know the FFE has significant advantages over the Leaf in this respect, but until we get a bunch of people who have kept their cars through many miles and years, how can we know what degradation will occur?

Surely Nissan thought there wasn't a problem. I don't want to be the one who finds out that Ford underestimated the degradation because I will still need to get to work and back, and if the car can't do it, I'm hosed.

I'm usually in the top 10 for distance driven in a month (per the myfordmobile web site) and I think it's important to safeguard the battery. Those driving 10K miles and year and short ranges don't need to worry, but I think I need to be careful.