Suggested State of Charge for long battery life

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Olagon

Well-known member
Joined
Oct 23, 2014
Messages
169
Anyone try to charge their FFE less than 100% to improve battery life? If so, tips on how to stop a charge at a certain percentage?

Thanks!
 
Ford is very conservative with regards to battery use. Even when the car says its 100% full the battery is really only about 90% full. Just charge it up and drive it.

In addition, there are quite a few people on here with significant amount of miles on their FFE (I'd bet some of them are approaching 30,000 miles) with no appreciable loss of battery.

Drive it and enjoy.
 
While everything Jmueller says above is true, (i.e, you don't need to worry) for the most conservative practice:

1. Charge only to the amount you need to reach your next charge point with a comfortable reserve

2. Charge as late as practical so that the battery spends less time at a high state of charge. Also, in many cases the battery is cool until charged, so this practice leads to a lower average battery temperature (usually...)

In my particular case, at work I park in the shade in the morning and charge up around 4 in the afternoon. That way, my battery sits at 80 or 90 degrees and 25% SOC most of the day. If I would charge up first thing in the morning like most of my co-workers, my battery would sit at 98 degrees and 90% SOC most of the day.

3. Charge with higher power rather than lower, since this allows later starting. 110V charging is NOT easier on the battery than 6 kW charging.

But again, these batteries seem to be quite robust. Do not worry if you don't do as I'm suggesting all the time, or if you chose not to bother at all.

One particularly good scientific reference paper:

Hoke et al Accounting for Lithium Ion Battery Degradation in Electric Vehicle Charging Optimization
DOI10.1109/JESTPE.2014.2315961, IEEE Journal of Emerging and Selected Topics in Power Electronics

You can access this paper at:

https://www.academia.edu/6878507/Accounting_for_Lithium-ion_Battery_Degradation_in_Electric_Vehicle_Charging_Optimization
(requires free signup)


But again, this car does NOT show the kind of problems that plague the Leaf.
 
Olagon said:
Anyone try to charge their FFE less than 100% to improve battery life? If so, tips on how to stop a charge at a certain percentage?
I do roughly as michael suggests. Using http://www.myfordmobile.com (or the mobile ap. version) lets me estimate state of charge and when I want to stop it for my driving that day.
To stop it, I go out to the car and press the small lever to stop it (about a second, until the EVSE interrupts the current, to reduce deterioration of the contacts), then pull the whole connector out.
You can do something like that with choice of starting time and Value Charge settings, but it is easier for me to walk to the car. (If I forget to stop the charge, figure it is not a big deal.)
 
JTCalif said:
To stop it, I go out to the car and press the small lever to stop it (about a second, until the EVSE interrupts the current

Which lever?
 
Olagon said:
JTCalif said:
To stop it, I go out to the car and press the small lever to stop it (about a second, until the EVSE interrupts the current
Which lever?
I think JTCalif is referring to the release latch on the top of the J1772 handle that you have to push (usually with your thumb, as you grip the handle) in order to release the handle from the inlet. I think most people would perceive it as a "button", but perhaps on JTCalif's handle it looks more like a "lever".

Anyway, not only does pressing the latch physically release the handle, it also breaks one of the signalling connections (the "pilot", I think) that EVSE and car use to communicate, letting the EVSE and car know that the power should be turned off (since, presumably, the handle is about to be removed).

Anyway, if you wait a moment after pressing the latch before removing handle from the inlet, as JTCalif suggests, this should ensure that power has definitely been removed from the remaining J1772 connections (the high voltage ones) before you physically disconnect them. Supposedly, this is advantageous, as the high voltage connectors won't suffer as much corrosion as "yanking" the handle out immediately (when power might still be flowing), which could result in micro-arcing between the high-voltage contacts and result in increased corrosion over time (as I understand it).
 
WattsUp said:
Olagon said:
JTCalif said:
To stop it, I go out to the car and press the small lever to stop it (about a second, until the EVSE interrupts the current
Which lever?
I think JTCalif is referring to the release latch on the top of the J1772 handle that you have to push (usually with your thumb, as you grip the handle) in order to release the handle from the inlet. I think most people would perceive it as a "button", but perhaps on JTCalif's handle it looks more like a "lever".

Anyway, not only does pressing the latch physically release the handle, it also breaks one of the signalling connections (the "pilot", I think) that EVSE and car use to communicate, letting the EVSE and car know that the power should be turned off (since, presumably, the handle is about to be removed).

Anyway, if you wait a moment after pressing the latch before removing handle from the inlet, as JTCalif suggests, this should ensure that power has definitely been removed from the remaining J1772 connections (the high voltage ones) before you physically disconnect them. Supposedly, this is advantageous, as the high voltage connectors won't suffer as much corrosion as "yanking" the handle out immediately (when power might still be flowing), which could result in micro-arcing between the high-voltage contacts and result in increased corrosion over time (as I understand it).
I believe that some owners have reported that they get the "accidental unplug while charging" message when yanking the handle out too quickly. I always press the button and wait until I hear the EVSE relays click that it is turned off before removing the handle. It takes about 1 second for the EVSE to respond at most.
 
Wow I learned something new! Don't just yank out an EVSE. That's what I have been doing for two years. Click, wait, then pull.
 
hybridbear said:
I believe that some owners have reported that they get the "accidental unplug while charging" message when yanking the handle out too quickly. I always press the button and wait until I hear the EVSE relays click that it is turned off before removing the handle. It takes about 1 second for the EVSE to respond at most.
I got those warning messages before.
Thanks for the excellent tip - I will now try to remember to wait a little bit after pressing the button before unplugging the connector. Too bad that isn't in the user manual. We still need a dedicated thread for these "FFE User Tips" I think.

I also hear the EVSE's relays click every few minutes when the connector is plugged into the car and not charging - is that normal?
 
Olagon said:
Wow I learned something new! Don't just yank out an EVSE. That's what I have been doing for two years. Click, wait, then pull.
The advice to wait mostly only applies to your own private EVSE, which most people "stop" simply by removing the handle. Pressing the release button is the first signal the EVSE gets to cut power, and it might take a moment.

When charging in public, for example at a ChargePoint station, the power is cut when you swipe your RFID card upon return to the station, in order to let the station know you are done. By the time you walk around to the handle and remove it from your car, the current has already been stopped. Basically, the current stops the instant the station registers your RFID "done" signal -- and, with the FFE, you can actually hear the "clunk" of the high-voltage relays disengaging the instant after swiping your card. So, you could safely "yank" under those circumstances.

But still... it is probably a good habit to develop when removing any charging station handle to always "press, wait, remove".

And don't forget to shake a little to make sure the last electrons dribble out. ;)
 
Olagon said:
Anyone try to charge their FFE less than 100% to improve battery life? If so, tips on how to stop a charge at a certain percentage?
Sometimes I plug the L1 charge cord into a 15A timer that I use for holiday lights, works like a charm. Usually I don't bother since I wake up early enough to unplug manually. Some folks (on various forums) claim that using timers is a no-no, but whenever I've challenged it by asking for documented proof, I was met with silence. There are others on the Volt forum that do the same with no issues. If anyone here knows of any documented evidence that this is an issue, please post!

BTW, I only bother with stopping the charge at about 75% when I know I'll be leaving the car sitting all day on the driveway in 100F+ heat. Totally agree with most folks around here that Ford did a great job of protecting the battery.

Wrote about this battery life subject a while back, with references to a few articles... might need some updating...

http://ev-vin.blogspot.com/2013/10/prolonging-life.html
 
v_traveller said:
Sometimes I plug the L1 charge cord into a 15A timer that I use for holiday lights, works like a charm. Usually I don't bother since I wake up early enough to unplug manually. Some folks (on various forums) claim that using timers is a no-no, but whenever I've challenged it by asking for documented proof, I was met with silence. There are others on the Volt forum that do the same with no issues. If anyone here knows of any documented evidence that this is an issue, please post!
I can think of no reason why this would be bad. The only potential downside I can see is that if the charger is pulling the full 12A when the timer shuts off it will be hard on the contacts of your 15A rated timer. If your timer is cheaply made it likely would significantly shorten it's life and may pose a fire hazard. I came home one day to find the timer on my fish tank a black charred mass of carbon with bits of copper. I got lucky it didn't burn my house down.
 
triangles said:
I can think of no reason why this would be bad. The only potential downside I can see is that if the charger is pulling the full 12A when the timer shuts off it will be hard on the contacts of your 15A rated timer. If your timer is cheaply made it likely would significantly shorten it's life and may pose a fire hazard. I came home one day to find the timer on my fish tank a black charred mass of carbon with bits of copper. I got lucky it didn't burn my house down.
This is my thinking. Thus it is a much greater issue if you were to attempt to disconnect power on the Level 2 EVSE if it were pulling its full draw (up to 30 amps @ 240V).
 
WattsUp said:
When charging in public, for example at a ChargePoint station, the power is cut when you swipe your RFID card upon return to the station, in order to let the station know you are done. By the time you walk around to the handle and remove it from your car, the current has already been stopped. Basically, the current stops the instant the station registers your RFID "done" signal -- and, with the FFE, you can actually hear the "clunk" of the high-voltage relays disengaging the instant after swiping your card. So, you could safely "yank" under those circumstances.
I didn't know that I was supposed to do this at ChargePoint stations so I just ended my session by unplugging the EVSE from my car. Then ChargePoint sent me an e-mail requesting that I use my RFID card to turn off the station before disconnecting my car. I have only used one ChargePoint station since and I did not remember that time...it's hard when I'm so used to not having that extra step when charging at home or at Goodwill.
 
hybridbear said:
I didn't know that I was supposed to do this at ChargePoint stations so I just ended my session by unplugging the EVSE from my car. Then ChargePoint sent me an e-mail requesting that I use my RFID card to turn off the station before disconnecting my car. I have only used one ChargePoint station since and I did not remember that time...it's hard when I'm so used to not having that extra step when charging at home or at Goodwill.
I used to simply unplug the car to stop my ChargePoint session. I would use that to see how long it took to get the text message from ChargePoint saying: "Hey someone unplugged your car" (in some cases I still had the plug in my hand when my phone beeped, in other cases it was hours later..stupid AT&T).

So far I've used ChargePoint about every other month on average...
 
I didn't know you could turn off a Chargepoint EVSE by swiping your card.

I use Blink public EVSEs most frequently and looked carefully at the screen during the authorization and afterwards to figure out if there was a button or procedure for ending the charging session. I get the Blink "unexpected disconnection" message every time I used Blink. My recollection is that the screen just instructs you to unplug when you're done.

I'll try swiping my card again at the end of the session. Maybe it's just something you're supposed to know.

I watched more carefully when unplugging my FFE today from the Clipper Creek HCS-40 at work. I've never gotten an "unexpected disconnection" message when using the Clipper Creek unit.

I held the locking lever down without pulling the J1772 connector out, and heard the EVSE contactor open and saw the Charging LED go out less than a second later. I think that's my new standard operating procedure.
 
Kakkerlak said:
I didn't know you could turn off a Chargepoint EVSE by swiping your card.
Yeah, that's the "graceful" way to end your charging session. It lets ChargePoint know that that real user of the station has returned (versus somebody else rudely unplugging your car).

You can even turn them on and off remotely with the ChargePoint app.
 
Kakkerlak said:
I didn't know you could turn off a Chargepoint EVSE by swiping your card.
I think that varies, from one station (or group of stations) to another.
Have tried using "swipe" to stop charge at the array of Chargepoints by the new Target near me, and that did nothing I could see. Good if that works some places.
 
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