How can you use battery capacity without driving? Can this improve battery capacity?

[EVDRIVER]

This is just my 2 cents, but cycling the battery is using the battery, whether it is to run the heater or to move the car. I would advise against running the heater to use up battery power, your just adding cycles or "miles" to the battery for no useful reason.

As Tom T said, it is time and cycles that degrade a battery. I would add to that, leaving the battery at a high state of charge isn't the best for the battery as well. So if your not using the car that much just don't top it off when your done.

I find the biggest change I see in capacity or Hx is when I run the battery down pretty low, to LBW or VLBW. But honestly I don't think that "helps" the battery it just gives the car a better picture of the actual battery capacity and adjusts accordingly.

+1. None of this makes sense to me and if you need to cycle the pack for a few needed percent then the car is being used outside it's useful parameters not to mention this is a complete waste of energy.

 

[EVDRIVER]

Update: When I started to leave the car with the heater running vs. driving it, the stats froze for a day then went down 2 days in a row. 2 days ago I started to drive it to cycle the battery and now the stats are starting to go back up.

Maybe the slow pull of power from the battery with the heater isn't good enough compared to the power the motor pulls from of the battery driving, especially the freeway.

Perhaps you pack is simply cold and using it will warm and expand capacity. This can happen with longer cycles or high-rate short discharges. I'm not sure I'm following any of the logic or reasoning behind doing any of this and why it's needed, if anything you are shortening your pack life and wasting energy for no real benefit.

 

[LeafMuranoDriver]

Perhaps you pack is simply cold and using it will warm and expand capacity. This can happen with longer cycles or high-rate short discharges. I'm not sure I'm following any of the logic or reasoning behind doing any of this and why it's needed, if anything you are shortening your pack life and wasting energy for no real benefit.

What is "cold" for the Leaf? Cold is somewhat subjective.
The coldest I have seen my battery is in the 50's since the winter began. After I charge, it's usually low to mid 60's.

I'm just testing for my own purposes. It's upsetting that the capacity has dropped 13% and I'm trying to see what I can do to bring it back up. It has come back up 3% so far.

It may shorten the life of the pack in the long run but I'm leasing and planning to turn it in at the end of 3 years. I would rather have more capacity now than later.

 

[EVDRIVER]

Perhaps you pack is simply cold and using it will warm and expand capacity. This can happen with longer cycles or high-rate short discharges. I'm not sure I'm following any of the logic or reasoning behind doing any of this and why it's needed, if anything you are shortening your pack life and wasting energy for no real benefit.

What is "cold" for the Leaf? Cold is somewhat subjective.
The coldest I have seen my battery is in the 50's since the winter began. After I charge, it's usually low to mid 60's.

I'm just testing for my own purposes. It's upsetting that the capacity has dropped 13% and I'm trying to see what I can do to bring it back up. It has come back up 3% so far.

It may shorten the life of the pack in the long run but I'm leasing and planning to turn it in at the end of 3 years. I would rather have more capacity now than later.

Look at Tony's range chart and the temp variations. If a loss of 3% is that critical that you are going to cycle the pack and waste energy to regain it I think you may have bought the wrong car or are looking at pack data far too much. I simply don't get the process or logic here at any level.

 

[LeafMuranoDriver]

Look at Tony's range chart and the temp variations. If a loss of 3% is that critical that you are going to cycle the pack and waste energy to regain it I think you may have bought the wrong car or are looking at pack data far too much. I simply don't get the process or logic here at any level.

I can admit I'm over analytical and OCD. I don't think I bought the wrong car.

It's not a loss of 3% I care about, it's 13% that's bothering me. I've gained 3% back so far.

Tony's range chart says, +1% for each 8F above 70F and -1% for each 4F below 70F. I don't think it really relates to my capacity loss but please check the first post and let me know what you think.

 

[DaveinOlyWA]

Might be a strange question but... can you use the battery without putting miles on the car?

Situation: I don't drive the Leaf enough and the battery capacity has really gone down over the past couple months. Up until a couple weeks ago, I was only driving about 5-10 miles per day on average, then started driving about 15-20 but that only stopped the losses but didn't get any better.

Starting this past Saturday, I've been trying to drive as much as I can (30+ miles/day) and the stats have started to increase, especially AHr (now at 56.03 from a low this past Saturday of 55.02.

Back to my question... what can I do to use the battery instead of just driving to nowhere for the sake of increasing the battery? Can I leave the heater or AC on all day/night? Is that safe? Anything else?

If you've been following the 2015: Battery Data Report @ 100% Charge thread you may have seen my rapidly decreasing stats. I've come to the conclusion that the car is not being driven/used and charged enough and the chargeable capacity continues to go down unless I start using/charging the battery more.

With the SOH at 99%, I have hope that the other stats may increase.

unless you are doing this to insure a warranty exchange within 60,000 miles, don't.

a temporary increase in battery stats is just that, temporary. loss from cycling the battery is permanent and does remove range from the back end. if you are leasing, it might not be a concern but doesn't say much for the next owner...

 

[knightmb]

a temporary increase in battery stats is just that, temporary. loss from cycling the battery is permanent and does remove range from the back end. if you are leasing, it might not be a concern but doesn't say much for the next owner...

I read this a lot also and it does concern me. It would be like your friend asking how best to remove structural sections of his leased vehicle for scrap metal selling but hold up enough to past inspection when returned for the end of the lease. I think since dealers are just looking for cosmetic damage on the outside, never think to check for the expensive damage on the inside (battery) and thus the next owner is the one to find the surprise. Kind of like putting sawdust in a transmission to make it run nice for test drive / purchase and then the new owner brings it home to find a destroyed gear box.

 

[LeafMuranoDriver]

I really think cycling the battery is good for it. There are 2015's out there with over a year of driving and 10k+ miles and still have 292 GIDs.

Driving and charging daily is the key. I'm no longer letting the car sit with the heater on just to use battery, the stats stalled.

Blue is where I was at the lowest. Green is when I started to drive more, red is when I tried to use the heater instead of driving, then I stopped and went back to driving.

Stats are climbing back every day now. The chart based on time really shows it. I charge exactly the same as I did when the stats were dropping.

In 3 weeks...
GID's up 5.1%
AHr up 4.9%
kWh up 4.9%
Hx up 6.5%

 

[Valdemar]

These numbers are just estimates that the BMS produces using the algorithms that Nissan coded in. If you cycle more the estimates may become more precise but your battery doesn't change and cycling isn't good for it long term. Do you also track the energy from the wall required to charge the pack from a known SOC level such as LBW to full? Does it track with other stats?

 

[jpadc]

a temporary increase in battery stats is just that, temporary. loss from cycling the battery is permanent and does remove range from the back end. if you are leasing, it might not be a concern but doesn't say much for the next owner...

These numbers are just estimates that the BMS produces using the algorithms that Nissan coded in. If you cycle more the estimates may become more precise but your battery doesn't change and cycling isn't good for it long term. Do you also track the energy from the wall required to charge the pack from a known SOC level such as LBW to full? Does it track with other stats?

I read this a lot also and it does concern me. It would be like your friend asking how best to remove structural sections of his leased vehicle for scrap metal selling but hold up enough to past inspection when returned for the end of the lease. … Kind of like putting sawdust in a transmission to make it run nice for test drive / purchase and then the new owner brings it home to find a destroyed gear box.

I keep reading all this “traditional wisdom” about how cycles kill the battery but when I ask about Brian’s battery stats at 50k miles with all the cycles he has put on that battery driving 28k across North America in 100 days (http://www.mynissanleaf.com/viewtopic.php?f=24&t=20231) with no bars lost (how many of you can say that at 50k miles) all I hear on the board in response is crickets. Again, we don’t know the numbers when he started the trip, but I think everyone here who says “cycles bad” needs some explanation for this:

 

[cwerdna]

I keep reading all this “traditional wisdom” about how cycles kill the battery but when I ask about Brian’s battery stats at 50k miles with all the cycles he has put on that battery driving 28k across North America in 100 days (http://www.mynissanleaf.com/viewtopic.php?f=24&t=20231) with no bars lost (how many of you can say that at 50k miles) all I hear on the board in response is crickets. Again, we don’t know the numbers when he started the trip, but I think everyone here who says “cycles bad” need some explanation for this:

FWIW, there was a comment in in https://www.facebook.com/groups/seattlenissanleaf/ (I posted about this at http://www.mynissanleaf.com/viewtopic.php?p=447252#p447252) where someone in the PNW stated "There is SUBSTANTIAL evidence that 2013 and 2014s don't lose capacity as fast as 2011-12s. Whether that's due to a chemistry change or other factors, it's definitely happening. There's no way a 2011-12 could go 75,000 miles without losing a bar, but I know of several 2013s that have."

Unfortunately, the link that I posted might be dead as the thread on that group might've been deleted.

Brian's car was bought in Dec 2013, IIRC and built just a few week's before. So, his car is only 2 years old and didn't go through a hot summer like my previous one (leased near end of 7/2013, built 6/2013) and my current owned one (built 5/2013, 1st in service date near end of 6/2013). And, for all we know, maybe the above assertion is right re: 2013 batteries, at least ones after some "magic" date (e.g. sometime after build month of 3/2013?).

Also, per http://www.weather.com/weather/monthly/l/14020:4:US, it seems he resided in a relatively mild climate w/summers that don't get that hot.

 

[jpadc]

FWIW, there was a comment in in https://www.facebook.com/groups/seattlenissanleaf/ (I posted about this at http://www.mynissanleaf.com/viewtopic.php?p=447252#p447252) where someone in the PNW stated "There is SUBSTANTIAL evidence that 2013 and 2014s don't lose capacity as fast as 2011-12s. Whether that's due to a chemistry change or other factors, it's definitely happening. There's no way a 2011-12 could go 75,000 miles without losing a bar, but I know of several 2013s that have."

Unfortunately, the link that I posted might be dead as the thread on that group might've been deleted.

Brian's car was bought in Dec 2013, IIRC and built just a few week's before. So, his car is only 2 years old and didn't go through a hot summer like my previous one (leased near end of 7/2013, built 6/2013) and my current owned one (built 5/2013, 1st in service date near end of 6/2013). And, for all we know, maybe the above assertion is right re: 2013 batteries, at least ones after some "magic" date (e.g. sometime after build month of 3/2013?).

Also, per http://www.weather.com/weather/monthly/l/14020:4:US, it seems he resided in a relatively mild climate w/summers that don't get that hot.

All true, but my question is based on the fact that there are plenty of '15s here (like OPs) and '13s (like mine also built in late '13) that are not showing as good of stats with far less miles and equally nice climates. It would seem like the LEAF's battery (at least '13s and beyond) acts a bit more like "use it or loose it" which is very different than "cycles bad." All of which makes LeafMuranoDriver's (OP's) crazy sounding thread thread title (this one) seem not so crazy.

 

[Valdemar]

Given I was able to put almost twice as many miles before losing 4 bars than some over the same time and in the same climate I tend agree it does seem that calendar losses dominate over cycling even for 11-12 cars, but cycling definitely has its effects as well.

 

[cwerdna]

All true, but my question is based on the fact that there are plenty of '15s here (like OPs) and '13s (like mine also built in late '13) that are not showing as good of stats with far less miles and equally nice climates. It would seem like the LEAF's battery (at least '13s and beyond) acts a bit more like "use it or loose it" which is very different than "cycles bad." All of which makes LeafMuranoDriver's (OP's) crazy sounding thread thread title (this one) seem not so crazy.

I can't speak to "cycles bad" vs. Brian's results and honestly, I haven't followed discussion of SOH vs. Hx vs. actual capacity, as the SOH and Hx values I don't think are well understood.

(Someone correct me if I'm wrong on this, please.)
AFAIK, Nissan hasn't documented any of these values and but we know these values tend to go down over time and are low on cars w/degraded batteries. We also don't know what Nissan intended these numbers to represent along w/how their accuracy, precision, error range, caveats, firmware/algorithm bugs, etc. Hell, for all we know, they might internally document one or both of these as buggy or to ignore, or they're only valid in certain conditions (e.g. temp range, mileage, etc.) or after a certain set of events has passed (e.g. x # of cycles from 100% down to xx%).

Not to go too OT, for ICEV emissions tests, in states that do them and check via OBD2 port, a readiness flag has to be set (see "Readiness Flags" under http://www.autotap.com/techlibrary/obdii_and_emissions_testing.asp, for example). http://www.toyotapart.com/READINESS_MONITOR_DRIVE_PATTERNS_T-EG02-003.pdf has examples of the quickest method to trigger the tests and thus reach smog test ready state.

To quote from a PDF copy of the manual I got from Turbo3, which should be the same as what's in the app's help.

SOH State of Health is another indication of the battery's ability to hold and release energy and is reported as a percentage. When the battery is new SOH=100%. When SOH drops to 85% for a month or so the Leaf loses the first capacity level segment displayed on the right side of the Leaf's central dash display. The capacity gauge is the rightmost outer curved column of segments next to "1" at the top and "0" at the bottom with the last two segments being colored red.
...
Hx The meaning of this number is not fully understood but it appears to be inversely related to the battery internal resistance. As the internal resistance of the battery pack increases it is thought this percentage decreases. As internal resistance increases more energy is lost within the pack and the pack heats up more under load.

For all we know, Brian's climate + current driving habits (e.g. presumably very long trips w/cycles from 100% to almost dead, rinse and repeat) has made these numbers go up but his actual capacity is significantly worse than what the numbers lead us to believe.

On one of the Facebook threads, one guy asserted that long trips tend to make these value rise. This was news to me, since I don't track discussion of Hx and SOH. And, for all we know, those of us who have shallow discharges may have "invalid" values or ones that are known to be off by x due to shallow discharges.

It'd be interesting to know how correlated these are w/actual battery capacities via a discharge test esp. on 2 cars of almost identical age, identical climates but treated differently (short vs. long drives) and one w/much better SOH and Hx numbers than the other, like what the guys at http://avt.inel.gov/fsev.shtml do (e.g. look for battery testing + what's under 2012 Leaf). I doubt we'll ever know since they don't use Leaf Spy, AFAIK.

All we have now are values that Nissan puts on the CAN bus that the BMS/battery controller advertises/responds with.

 

[minispeed]

As far as people think that cycles are bad. I have a 17 month old 2015 with 55k km (35k miles), over 115ish QC and 1200 or so L1/L2 and still show 292 gids and 100% SOC (63ish Ah).

For those who have said that cycling the battery in a garage is like putting extra wear and tear on the car that is hidden by the lower millage, or even as extreme as selling off hidden parts of the car for scrap that's a pretty far fletched idea.

2 drivers can drive the same amount of miles and one could baby it the other floor it and they would have much different cycles on the battery. If you want to only cycle the battery but not cause other wear like tires/brakes/suspension then doing it stationary a few times isn't going to produce any kind of deterioration anywhere near an owner who drives the car like they stole it. That's probably a common way leased cars have been driven too.

The same thing has been true on almost any ICE car ever. Almost none of them have hr meters for the engine. These can give a good indication of wear and tear that the ODO doesn't always show. At my work we have a fleet of different cars, some heavy duty ones have hr gauges and show run times with an avg speed of about 12mph but we hardly ever drive that slow. These cars are routinely junk with 40k miles on them.

 

[DaveinOlyWA]

I keep reading all this “traditional wisdom” about how cycles kill the battery but when I ask about Brian’s battery stats at 50k miles with all the cycles he has put on that battery driving 28k across North America in 100 days (http://www.mynissanleaf.com/viewtopic.php?f=24&t=20231) with no bars lost (how many of you can say that at 50k miles) all I hear on the board in response is crickets. Again, we don’t know the numbers when he started the trip, but I think everyone here who says “cycles bad” need some explanation for this:

FWIW, there was a comment in in https://www.facebook.com/groups/seattlenissanleaf/ (I posted about this at http://www.mynissanleaf.com/viewtopic.php?p=447252#p447252) where someone in the PNW stated "There is SUBSTANTIAL evidence that 2013 and 2014s don't lose capacity as fast as 2011-12s. Whether that's due to a chemistry change or other factors, it's definitely happening. There's no way a 2011-12 could go 75,000 miles without losing a bar, but I know of several 2013s that have."

Unfortunately, the link that I posted might be dead as the thread on that group might've been deleted.

Brian's car was bought in Dec 2013, IIRC and built just a few week's before. So, his car is only 2 years old and didn't go through a hot summer like my previous one (leased near end of 7/2013, built 6/2013) and my current owned one (built 5/2013, 1st in service date near end of 6/2013). And, for all we know, maybe the above assertion is right re: 2013 batteries, at least ones after some "magic" date (e.g. sometime after build month of 3/2013?).

Also, per http://www.weather.com/weather/monthly/l/14020:4:US, it seems he resided in a relatively mild climate w/summers that don't get that hot.

in a blog I posted yesterday with readings taken yesterday. granted its a 2013 but there is some loss on the 2015. not a lot which is what we all wanted right? this still does not mean that "exercising" the battery makes it stronger in the long term. I think we are still wrestling with the inadequacy of precise charge measurements. lets not let these small improvements lead us to believe that we have actually made our battery stronger

 

[RegGuheert]

in a blog I posted yesterday with readings taken yesterday. granted its a 2013 but there is some loss on the 2015. not a lot which is what we all wanted right? this still does not mean that "exercising" the battery makes it stronger in the long term. I think we are still wrestling with the inadequacy of precise charge measurements. lets not let these small improvements lead us to believe that we have actually made our battery stronger

As someone with 30,000 miles on my MY2011 LEAF which now shows 52.0Ah, I will say I am impressed to see you have over 66Ah of capacity in your MY2013 after driving MORE miles.

Clearly some improvements have been made, both in the battery AND in the ability of the OBC to fully charge the battery as it degrades.

 

[jpadc]

in a blog I posted yesterday with readings taken yesterday. granted its a 2013 but there is some loss on the 2015. not a lot which is what we all wanted right? this still does not mean that "exercising" the battery makes it stronger in the long term. I think we are still wrestling with the inadequacy of precise charge measurements. lets not let these small improvements lead us to believe that we have actually made our battery stronger

I'm inclined to agree with you about reading too much into small changes, but I do wonder about patterns. Here is my first year of ownership data from Leaf Spy Pro. I bought my 2013 LEAF new in later December of 2014. It mostly sat on the dealer lot for over a year. When I got it it had under 800 miles. One year later, the car has 10,000 miles on it. See plot below:

Some notes..
The battery stats are a bit down when new (as it mostly sat unused for the first year on the dealer lot in Iowa [so not a hot climate]) Once I got it to Indy and started using it regularly the stats jump up to a "normal" new 2013 level and soon I'm charging to a max of 80% and you can see how fast the Ahr and SOH starts dropping. I then go back to charging to 100% all the time and the battery health seems to improve a bit. By May I have to put the car away for 2.5 months and I left it at 50% charge with a Battery Tender on the 12 volt. By late August I start driving it again and I get the Ahrs back on a somewhat upward swing as I drive it regularly and charge to 100%.

So I look at this and then your stats ,and Brian's stats, and I think, sitting too much and not using the battery a lot is not as good using it as much as others do...

 

[LeafMuranoDriver]

So I look at this and then your stats ,and Brian's stats, and I think, sitting too much and not using the battery a lot is not as good using it as much as others do...

Exactly my point.

I stopped driving and charging just to get the stats up (went from avg. 50 miles per day to 10-20 miles) and the next 2 charges over 5 days dropped more than I would have thought.

From my worst (see sig), I got up to 279 GIDs / 21.6 kWh, 2 days later it only charged to 275 GIDs / 21.3 kWh and yesterday was down to 271 GIDs / 21.0 kWh. No difference in charging and the temps have actually gone up a few degrees over that time period.

I'm lucky I don't have to drive so much but it's not helping the usable capacity of my Leaf. Maybe it's extending the degradation but I want more usable capacity now and do not care what happens after 3 years. (I of course do everything I can to take care of it, least amount of heat, charge at coolest times of day, etc...)

 

[GetOffYourGas]

As far as people think that cycles are bad. I have a 17 month old 2015 with 55k km (35k miles), over 115ish QC and 1200 or so L1/L2 and still show 292 gids and 100% SOC (63ish Ah).

For those who have said that cycling the battery in a garage is like putting extra wear and tear on the car that is hidden by the lower millage, or even as extreme as selling off hidden parts of the car for scrap that's a pretty far fletched idea.

2 drivers can drive the same amount of miles and one could baby it the other floor it and they would have much different cycles on the battery. If you want to only cycle the battery but not cause other wear like tires/brakes/suspension then doing it stationary a few times isn't going to produce any kind of deterioration anywhere near an owner who drives the car like they stole it. That's probably a common way leased cars have been driven too.

The same thing has been true on almost any ICE car ever. Almost none of them have hr meters for the engine. These can give a good indication of wear and tear that the ODO doesn't always show. At my work we have a fleet of different cars, some heavy duty ones have hr gauges and show run times with an avg speed of about 12mph but we hardly ever drive that slow. These cars are routinely junk with 40k miles on them.

I agree. Consider another scenario - two Leafs identical in age and use patterns, but different climates. The first Leaf, in a warm climate, is fired up and driven without ever using the climate control to preheat/precool the car. The other Leaf, in a severe climate, is preconditioned daily. The car is preheated in the winter and precooled in the summer. This preconditioning happens at the end of the work day, where the driver does not have access to a plug (but otherwise has plenty of power to get home) and so puts extra cycles on the battery.

Did the second driver abuse his car? Or did he simply use it in a reasonable manner, given his situation? I would argue the latter.