battery AHr SOH and Hx improved since 3/29/17

I bought a used 2014 leaf with approximately 9500 miles back in March for my kid. It had 11 bars.

As we drove the car, it seems the battery improved slowly over time.

xxxxxxxxx ARr SOH Hx
3/20/17 55.956 85% 83.22

5/2/17 56.885 86% 85.39

11/16/17 58.343 89% 88.4

From December 9th till now the numbers have dipped down to what they are now. That's also when we hit the lower 30's.
12/12/17 57.820 88% 87.27 It has been below 20 most of the last 3 days (not sure that makes a difference).

Has any other used owner seen their battery stats improve over time?

I'm sure the health of the battery has probably topped out, but that's ok. I think the climate in northern Ohio may actually be better for battery degradation. Also when she goes to college, it will become my work car. I'll keep it until I can't make the 28 commute to and from work and only drive my ICE when my wife and I go on road trips.

It has only been quick charged 2 times by us and 4 times total. Otherwise, we just use trickle charger that came with the car.

Just thought I would post this because I thought this was interesting.


(edited 3 times because I had a bad cold/fever lol)

When you say SOC are you actually talking about SOH?

AHr, SOH and Hx do seem to improve with deeper discharges (e.g. to quite low like below LBW) then charges to full vs. shallower charges and charges not to full. It's also been reported that DC FCing can also provide a temporary boost to the numbers. I can't confirm since my current Leaf dosen't have a CHAdeMO inlet.

Whether or not available capacity has actually improve with the instrumentation changes upward is debatable.

It's possible that the previous driver did shallow discharges and charges.

Edited my post, thanks.

Our first quick charge was 11/19/17. Only QC'ed to show my kid how to use a quick charge. All of the numbers (AHR, SOH, HX) were same as 11/16/17.

Our second QC was 12/09/17. Made my kid show me how much was learned from the first time. Numbers stayed the same before and after.

Great car and good in snow. Just wish the battery did better in cold temps.

Cold weather effects economy (range) for all cars, but EVs are a little worse. This article indicates as much as 30% reduction for a LEAF:

https://www.fleetcarma.com/cold-weather-fuel-efficiency/

Where I live, I think it's more like 20% on average over the winter months.

Hello,
I concur with the previous poster. Since getting the car in March you are prolly seeing the batt capacity ticking up because of warmer temps. I've had mine for 7 years and have plotted the cycle. The efficiency and capacity both make a nice sine wave.

Rxleaf said:

Has any other used owner seen their battery stats improve over time?

Click to expand...

It is important to remember that the numbers from Leafspy are the estimate of the battery management system, and these estimates can vary a lot. I've seen at least +10% -3%. I've seen 6% difference between charges. To get a more accurate measurement, you need a controlled discharge or a controlled charge at a known temperature.

Among other things, the BMS's estimate can be thrown off by DCQC sessions, length of drives, outside temperature and probably more.

AHr SOH and Hx did not change before or after the QC.

They have improved every month since we have owned the car.

We usually only charge to 100% at L1

Rxleaf said:

I bought a used 2014 leaf with approximately 9500 miles back in March for my kid. It had 11 bars.

As we drove the car, it seems the battery improved slowly over time.

xxxxxxxxx ARr SOH Hx
3/20/17 55.956 85% 83.22

5/2/17 56.885 86% 85.39

11/16/17 58.343 89% 88.4

From December 9th till now the numbers have dipped down to what they are now. That's also when we hit the lower 30's.
12/12/17 57.820 88% 87.27 It has been below 20 most of the last 3 days (not sure that makes a difference).

Has any other used owner seen their battery stats improve over time?

I'm sure the health of the battery has probably topped out, but that's ok. I think the climate in northern Ohio may actually be better for battery degradation. Also when she goes to college, it will become my work car. I'll keep it until I can't make the 28 commute to and from work and only drive my ICE when my wife and I go on road trips.

It has only been quick charged 2 times by us and 4 times total. Otherwise, we just use trickle charger that came with the car.

Just thought I would post this because I thought this was interesting.


(edited 3 times because I had a bad cold/fever lol)

Click to expand...

You are probably seeing two things in play.

Changing temps will change battery capacity. Warmer means more capacity but also the greater risk of degradation at an unacceptable level.

the other is probably a calibration reset of BMS. LEAFs seem to struggle with reporting the true state of the battery so deeper discharges increases numbers but I think its more the BMS reporting a truer picture of the battery state.

I did a lot of experimenting with my pack and quickly found that temperature changes which should bounce the numbers up as the mercury rises didn't seem to change numbers as significantly as I thought they would. In fact, it would seem the pack has to be rather cold to make a difference. I suspect I simply live in an area that rarely sees the temperatures needed.

Now that we are getting into colder weather including a 4 day stretch into the 20's, I would think that capacities would be reduced but that did not happen. Battery temps only dipped into the low to mid 40's so maybe I needed to park outside or something to see something but as mentioned above, I just ain't seeing it and with the large number of people here reporting numbers rising in Winter, its all very much a head scratcher.

**I notice posting your location is still not a required part of this site. Just another reason this place has diminished in value...

My experience here in Colorado is just the opposite of what some of you are describing. Warmer temperatures in the summer bring a drop in battery health & capacity. The cooler temperatures of winter increase the health and capacity of the battery, but the drop in efficiency more than counteracts that and thus lowers range. It is quite normal for these numbers to not be stable however, mine constantly move up and down. The general behavior throughout the year though is as I described. I nearly lost my first capacity bar in early September before things started to cool down and the health and capacity started to recover.

DaveinOlyWA said:

**I notice posting your location is still not a required part of this site. Just another reason this place has diminished in value...

Click to expand...

I raised this issue over 5 year ago (http://www.mynissanleaf.com/viewtopic.php?f=17&t=9260) and nothing's changed on this front.

Cleveland Ohio if that helps