How is your battery holding up?? Here are pictures of mine...

[rbort]

So I don't retype and upload pictures again, here is a link to a post I just made on the Cmax forum (I own a 2013 Cmax).  

 

After almost 2 years (build date June 13th, 2013), I'm still able to get 5.8kwh out of the battery.

 

http://fordcmaxenergiforum.com/topic/3786-happy-to-report-my-hvb-still-seems-to-be-doing-pretty-good-after-30k-miles/

 

How are you guys making out with the Fusions?

 

-=>Raja.

[jeff_h]

Hi Raja - not as well as you are, unfortunately.  

 

Mine now has 52k and max for a trip is normally 4.8-4.9, maybe up to 5.1 if the stars align, but it has been a drop-off from the routine 5.5-5.7 that I used to get when it was new. 

 

Similar situation for my wife's Energi which now has 36k, maybe go over 5.0 now and then but is about 4.8 in most cases.

 

However I remember seeing a chart on one of the C-Max forums (think it might have been the hybrid forum) of test results of long term degradation, and the curve showed that capacity degraded x% (I think it was about 10-15% or so) over the first 40k miles but then the same amount of degradation over the next 200k miles as occurred during the first 40k.  So I've seen a hit but wonder if that might flatten out a bit.

 

In any case, I don't really sweat it since it's a known that the capacity degrades over time - life is still good.

[Hybridbear]

I am tracking my battery health using Torque Pro to record the ETE at a full charge. Over time I will be able to see a pattern. The data recorded by the car for the Trip Summary is not the most accurate because it doesn't correctly account for the losses going in and out the pack during acceleration & regen braking. Focus Electric owners striving to discover capacity losses have discovered this and have determined that the only accurate way to measure capacity without an app like FORScan or Torque Pro is to start with a full charge and run the battery down to empty using the heater on full blast without moving the car.

[jeff_h]

I am tracking my battery health using Torque Pro to record the ETE at a full charge. Over time I will be able to see a pattern.

 

Good point - my notes above are simply based on the trip & charge log displays on the MFM site.

[rbort]

Yeah well I don't use the SG type tools on my car so I'm just looking at the output of what I can get from driving.  Its relative anyways, so if I can get 5.8 yesterday and I get less down the road well I know how its changing.

 

I'm not going to waste a charge cycle to run the heat and kill the battery that way, I'd rather benefit from that cycle and drive the car somewhere instead.

 

-=>Raja.

[larryh]

I suspect the amount of charging and depth of discharge has a significant impact on the state of health of the battery.  People who have a long commute to work, charge both at home and work, and completely discharge the battery in each direction will probably experience battery degradation much faster. 

 

In the summer, I only use about 2/3 of the charge in the battery for my commute to and from work.  In the winter, I use almost all of it.  So I experience greater depth of discharge of the HVB in the winter.

 

To determine battery degradation, you would need a regular route that you travel and with the same outside temperature.  The route and temperature have a significant impact on the amount of energy you can extract from the HVB. 

[TX NRG]

My 2013 used to get 5.5/5.6 kWh from a full charge but now as it approaches 25k miles it consistently only gets 4.4/4.5. That is 20% and a lot bigger drop off than what I expected.

[rbort]

 

My 2013 used to get 5.5/5.6 kWh from a full charge but now as it approaches 25k miles it consistently only gets 4.4/4.5. That is 20% and a lot bigger drop off than what I expected. 

I believe it all depends on how you treat the battery, read my best practices here:

 

http://fordcmaxenergiforum.com/topic/3668-hvb-long-term-best-practices/

 

When I first started talking about this on the forums, people thought none of it should matter as Ford built in all the safety guards, you won't notice anything day to day but over time as I said before it seems to make some difference.  

 

-=>Raja.

Edited May 24, 2015 at 01:14 AM by rbort

[rbort]

Interesting, I wonder if I should make a list:

 

Fusion:

 

Jeff-h:  56k miles, 4.9kwh

Jeff-h's wife:  36k miles, 5.0kwh

TX nrg: 25k miles, 4.5kwh

 

Cmax:

 

rbort: 31k miles, 5.8kwh

mitrals: 71k miles, 5.5kwh

honemch: 59k miles. 3.9kwh

 

I wonder if we should make this list grow to examine the data?

 

-=>Raja.

[jeff_h]

I wonder if we should make this list grow to examine the data?

 

I don't know about that, probably too many variables like temperatures, driving style, typical trips, etc.

[rbort]

Jeff,

 

What would be interesting is to hear about people's charging habits (not driving) and also how much they can get out of their battery max after x miles and years.

 

The point to that is that it doesn't matter what your driving habits are, if I come and drive your car with my habits (meaning acceleration, braking, etc), what can I get out of your car in kwh after you've been treating your battery a certain way for 2 years time.  You see what I mean?

 

-=>Raja.

[larryh]

Your driving style most certainly does matter.  It most likely outweighs any charging practices.  Some of the main factors in determining battery degradation are the number of charging cycles and average battery temperature.  If someone fully discharges the battery and recharges the battery twice a day for their commute to and from work, they are going to have much greater degradation than someone who charges once a day and does not fully discharge the battery.  Similarly, someone in the northern US will have less degradation than in the south.  

Edited May 24, 2015 at 02:37 AM by larryh

[rbort]

Absolutely Larry, but how you treat the battery does also make a difference.  Do you leave it plugged in all the time, do you recharge it after every little trip, etc.  All these factors add up to the life span story of the battery.  

 

-=>Raja.

Edited May 24, 2015 at 03:09 AM by rbort

[Hybridbear]

Isn't charging the battery when it's warm also more likely to lead to capacity loss from the little data we have? That's the main reason why we set our car to charge as late as possible at night. We want the battery to have as much time as possible plugged in but not charging to cool the HVB. Almost all the time in the summer when we come home and plug in the car immediately starts running the fan to cool the HVB. This is why we always plug in, we want the car to be able to cool the HVB anytime it sees fit.

[rbort]

Usually when you use batteries especially in the summer and they get warm you should let them rest (cool) before charging them back up again.  This is not always possible when you are driving places and you are on the road eating dinner and you need to recharge to keep going you have to plug in and charge back up.

 

Having the battery dwell at 100% charge for longer than needed is also bad for the battery and over time will lead to capacity loss.  So, the main reason to charge as late as possible it to not let the battery sit at 100% charge for more time than necessary.  This also gives the battery some time to cool though in hot weather its not going to drop in temp much.

 

When you plug in the car to charge the fan is going to run to try to keep the battery cool while charging as charging also elevates the battery temperature.  Higher rates raise the battery temp more than lower rates, though both 120v and 240v and not very high rates to be honest, 240v is about 0.43c or there abouts, 120v is like 0.13c and close to trickle charge levels.

 

 

 

This is why we always plug in, we want the car to be able to cool the HVB anytime it sees fit.

 

I believe that's bad and recommend against it.  Leaving the car always plugged in so the fan will run while charging will do more damage to the battery sitting at full charge all the time than any benefit you get running the fan while it was charging.

 

-=>Raja.

Edited May 24, 2015 at 11:39 PM by rbort

[Hybridbear]

I believe that's bad and recommend against it.  Leaving the car always plugged in so the fan will run while charging will do more damage to the battery sitting at full charge all the time than any benefit you get running the fan while it was charging.

 

-=>Raja.

Raja - please go back and read my post again. I don't think you correctly understood what I was saying. The car does not need to be charging to run the fan. You may be damaging your battery by not allowing it to cool as effectively. Our car is set to charge starting at 3:00 am every day. If we plug in when we get home in the afternoon the car will run the fan for potentially hours to cool down the battery before it charges. Thus we get the maximum benefit: the battery is as cool as possible when charging and also spends the least amount of time possible at a high SOC.

[rbort]

OK bear I understand now, yeah I never need my car fully charged every day so I never used the value charging (also because there isn't any difference for me in power pricing).  So I just plug it in and charge it when I need it.  If there was a way to tell the charger to charge to 60% and stop, then it would be good to plug it in and let it charge the next morning to 60% and stop automatically, but right now it will just go until its at 100%.

 

I got a question for you though, when you plug in your car right away to value charge, no matter what the car always charges the hybrid battery first before going into the wait cycle for the value charge.  Did you notice if the fan keeps running after this point, or is it only running when you're recharging the hybrid battery?

 

-=>Raja.

Edited May 26, 2015 at 05:33 AM by rbort

[larryh]

Last summer, ETE (Energy to Empty) at 100% SOC for the HVB was about 7.10 kWh.   This spring, it has been around 6.95 kWh.  The car generally charges to about 98% SOC.  So last summer, ETE at the start of a trip was normally 6.96 kWh and this spring it is normally 6.81 kWh.  The minimum ETE that you can discharge the HVB to before the ICE comes on is 1.0 kWh.  Thus last summer, the maximum energy I could get out of the HVB was 6.96 – 1.00 = 5.96 kWh.  This spring it is 6.81 – 1.00 = 5.81 kWh.

 

 

 

[Hybridbear]

OK bear I understand now, yeah I never need my car fully charged every day so I never used the value charging (also because there isn't any difference for me in power pricing).  So I just plug it in and charge it when I need it.  If there was a way to tell the charger to charge to 60% and stop, then it would be good to plug it in and let it charge the next morning to 60% and stop automatically, but right now it will just go until its at 100%.

 

I got a question for you though, when you plug in your car right away to value charge, no matter what the car always charges the hybrid battery first before going into the wait cycle for the value charge.  Did you notice if the fan keeps running after this point, or is it only running when you're recharging the hybrid battery?

 

-=>Raja.

We rarely deplete the battery that low. The fan will run for hours potentially if the HVB temp is high enough.

[rbort]

Interesting Bear, I should play around with the value charge so this way I can plug in the car when I get home and unplug it before I go to sleep just to use the fan on hot days this summer.

 

Larry, looks like I'm with you on the numbers, I recently got 5.8kwh out of my battery.  I think the most I ever got in the past is 5.9 though I don't seem to have saved any picture of that.

 

-=>Raja.

Edited May 26, 2015 at 03:50 PM by rbort

[Hybridbear]

I usually see an ETE of around 7.100 kWh with the Abs SOC showing 99.1-99.4%.

[larryh]

I'm not sure what to think of the measurements the car is reporting for plug-in energy consumed.  For my 60 mile commute this weekend, I recorded the energy consumed and regen'ed to the HVB.  The total amount of energy extracted from the HVB was 7.74 kWh.  Regen added 1.99 kWh of energy back to the HVB.  That's a net 7.74 - 1.99 = 5.75 kWh of plug-in energy consumed from the HVB.  During that trip, I recorded the second highest MPGe I have measured for my 60 mile commutes.

 

According to the BECM, the HVB started with 7.074 kWh of energy and ended up with 1.184 kWh of energy (I had about 0.184 kWh of energy left before the ICE would start).  That would suggest the HVB provided a net 7.074 - 1.184 = 5.89 kWh of plug-in energy.

 

The car's trip odometer reported the car consumed 5.6 kWh of energy.

 

Last year, the three different computations all matched closely for the commutes I recorded.  This year, for some reason, they are all out of sync.  I think the BECM is confused.

Edited May 31, 2015 at 01:22 AM by larryh

[Hybridbear]

I experienced something similar with the Focus Electric when I went to Faribault for work on Thursday. The southbound trip showed 8.6 kWh used on the Trip Summary but the ETE decreased by 9724 Wh. The northbound trip showed 7.8 kWh on the Trip Summary but the ETE decreased by 7580 Wh.

 

I also had one stretch of freeway where the range estimate was rising as I drove. This is because the ETE wasn't really decreasing even though I was consuming power from the HVB to drive. The a of a sudden my range estimate dropped by 10 miles because the ETE suddenly dropped by more than 1500 Wh.

Edited May 31, 2015 at 03:14 AM by Hybridbear

[larryh]

ETE started falling more rapidly than expected when SOC fell below 50%.  That made the range and SOC displayed in the car decrease faster during the second half of the trip vs. the first half.  The BECM must have decided that it got the initial ETE of 7.074 kWh wrong and was trying to correct the error.

Edited May 31, 2015 at 09:06 AM by larryh

[rbort]

Larry,

 

About the falling off quicker below 50%, that is generally a sign that some of the cells in the battery pack are not holding the same ETE as  others due to degradation.  When you charge up they all go to 100% or close to it, but when you discharge, the bad cells will crash before the rest rendering the remaining ETE in the good cells unuseable.

 

-=>Raja.