2013 Low Battery Capacity AHr Battery Degradation

[biggsy]

What's the lowest voltage you saw under load?

They were bouncing around a lot while driving but I think I saw something like 2.79 for just a second, when I slowed toward a stop they went back above 3.00.

 

[Computerizer]

Has anyone with a May-built 2013 been able to get any confirmation of problem from any diagnostics the dealers can do?

I've decided to keep my vehicle, though the dealer offered to exchange it, in order to try to get Nissan to acknowledge there's a problem and fix it. I'm just wondering if anyone else has been able to make any progress on that front.

 

[biggsy]

FWIW, my first charge back to 100% after going to turtle for the first time earlier this week. All of my stats improved to new highs, now showing:
AHr=64.03 prev high 63.31
SOH=97% prev high 96%
HX = 98.2 prev high 97.25
GIDs= 278 prev high 271

I have had my Leaf about six weeks now and the numbers keep improving.

 

[DaveinOlyWA]

FWIW, my first charge back to 100% after going to turtle for the first time earlier this week. All of my stats improved to new highs, now showing:
AHr=64.03 prev high 63.31
SOH=97% prev high 96%
HX = 98.2 prev high 97.25
GIDs= 278 prev high 271

I have had my Leaf about six weeks now and the numbers keep improving.

blogging about this but have you ever quick charged? reason I ask is because every time I do i see a significant jump in my readings. I think that extended periods in the cold depress the readings.

 

[biggsy]

FWIW, my first charge back to 100% after going to turtle for the first time earlier this week. All of my stats improved to new highs, now showing:
AHr=64.03 prev high 63.31
SOH=97% prev high 96%
HX = 98.2 prev high 97.25
GIDs= 278 prev high 271

I have had my Leaf about six weeks now and the numbers keep improving.

blogging about this but have you ever quick charged? reason I ask is because every time I do i see a significant jump in my readings. I think that extended periods in the cold depress the readings.

So far I have not quick charged or even Level 2, everything has been Level 1 with the EVSE that came with the car. As far as the cold, I park in the garage every night and here in southern tip of coastal South Carolina we have always gotten above freezing during the daytime.

 

[DougWantsALeaf]

My leaf has a SOH of 90% and 58 AHr. Does it matter that my battery pack was at 3 degrees C? (39 F)? Its about 0F outside today.

Car only has about 3400 miles on it, so 10% degredation seems a little high, especially since we are usually 80 chargers, and it has been only temperate and cold since we have had the car (in Chicagoland area).

Thanks

 

[Computerizer]

My leaf has a SOH of 90% and 58 AHr. Does it matter that my battery pack was at 3 degrees C? (39 F)? Its about 0F outside today.

Car only has about 3400 miles on it, so 10% degredation seems a little high, especially since we are usually 80 chargers, and it has been only temperate and cold since we have had the car (in Chicagoland area).

Thanks

Doug, can you look at the decal on the door frame of your car and see what its manufacturing date is?

Cold temperatures definitely do decrease capacity, but it shouldn't be that much at that temperature.

 

[DougWantsALeaf]

I will report back when my wife returns from work.

The other stat I have from Leaf Spy is a cell pairing voltage of 4.12 at near 100% charge per the car (between 98% and 100% - was preheating on L1 which pulls charge down a little).

is Hx the health percent? (if so that is also 90.01%).

Car was leased in May of 2013. 2 year lease.

 

[DaveinOlyWA]

I will report back when my wife returns from work.

The other stat I have from Leaf Spy is a cell pairing voltage of 4.12 at near 100% charge per the car (between 98% and 100% - was preheating on L1 which pulls charge down a little).

is Hx the health percent? (if so that is also 90.01%).

Car was leased in May of 2013. 2 year lease.

SOH is state of health. not sure what Hx means other than it does seem to wander up and down with ahr

 

[stjohnh]

My leaf has a SOH of 90% and 58 AHr. Does it matter that my battery pack was at 3 degrees C? (39 F)? Its about 0F outside today.

Car only has about 3400 miles on it, so 10% degredation seems a little high, especially since we are usually 80 chargers, and it has been only temperate and cold since we have had the car (in Chicagoland area).

Thanks

Doug, your car is probably normal. This whole thread is devoted to the topic of normal 2013 Leafs whose capacity and "health" NUMBERS seem low compared to 2011 and 2012 Leafs. The only way to be sure your battery is ok is to do a range test. The numbers reported by LeafSpy, LeafDD, etc have been "massaged" by Nissan's computer programming, to the point that it is not at all clear what the "capacity" (AHr), SOH (state of health) and Hx(some other number related to the battery) actually mean. Without further understanding by the smart people on this forum (I'm not one of them), we just don't know how to measure degradation in these newer Leafs. Only a range test (100% to Turtle- NOT almost to turtle) will tell you if your battery is ok.

 

[DougWantsALeaf]

Thanks StJohns

This morning with a battery pack at 29F, and an abient temp of -8F (-11F to -7F) I was able to go about 14 miles in 17% in stop and go traffic (10 - 45 MPH), which given the temp, seems reasonable. Once Chicago is back above 50F, I will do a full range test.

The temperatures have been so cold, its really hard to tell if I am seeing any significant range degredation yet.

 

[Berlino]

Since min cell voltage=3.00 is the trigger for turtle starting

Extreme conditions may throw this off. I turtled with 8 Gids, SOC = 8.5%, min voltage 3.352, battery temp -8°C.

Actually, perhaps the cold was throwing the instruments or LEAF Spy off. In either case, proceed with caution when battery temps are below 20°F.

After turtling, I drove about 25 meters, parked, and took this screen-shot:

Can this be correct? I understand that several factors influence voltage, but an average of 3.707 usually corresponds to an SOC% of 20-35%, not 8.5%

Then, another screen-shot, taken less than a minute later shows much different readings:

Can I trust either one?

 

[DaveEV]

Can I trust either one?

I'd bet that the first one was old data. It can take 10 seconds for that plot to fully settle, or so, and is really only useful when there there is no significant power being drawn from the battery, or if you're able to keep a very consistent load on the battery for an extended period of time.

 

[stjohnh]

Since min cell voltage=3.00 is the trigger for turtle starting

Extreme conditions may throw this off. I turtled with 8 Gids, SOC = 8.5%, min voltage 3.352, battery temp -8°C.

Actually, perhaps the cold was throwing the instruments or LEAF Spy off. In either case, proceed with caution

Cell impedence increases at low voltages and more at low temperatures. That means if the no-load min voltage is 3.3, like at a stop sign, then you start moving, unless you are very light footed, the load can easily drop the voltage to 3.0, triggering turtle. When you the stop to check the voltage you will still see 3.3v.

Lesson: at low soc (less than 10%), especially w a cold pack, drive at low speeds and accellerate gently if you want to make it home.

 

[crabasa]

Whew! Just made my way through this entire thread. I am the owner of a Leaf manufactured in June 2013 that has less than 800 miles on it and is exhibiting the low SOH/GID symptoms described in this thread. I am currently in the process of executing a range test from 100% down to Turtle.

My question is: what kind of range am I looking for? I know the answer varies based on driving style, elevation, type of road, temp, etc. But what is the range of the mileage I should look for? I saw a post earlier in this thread of someone who went 114 miles on a charge.

I'm trying to evaluate whether I should pursue a remedy with my dealer (car or battery swap) or whether my car is "fine". Would love everyone's thoughts. I will post my data once I'm done with my test.

--Carter

 

[stjohnh]

Whew! Just made my way through this entire thread. I am the owner of a Leaf manufactured in June 2013 that has less than 800 miles on it and is exhibiting the low SOH/GID symptoms described in this thread. I am currently in the process of executing a range test from 100% down to Turtle.

My question is: what kind of range am I looking for? I know the answer varies based on driving style, elevation, type of road, temp, etc. But what is the range of the mileage I should look for? I saw a post earlier in this thread of someone who went 114 miles on a charge.

I'm trying to evaluate whether I should pursue a remedy with my dealer (car or battery swap) or whether my car is "fine". Would love everyone's thoughts. I will post my data once I'm done with my test.

--Carter

Carter,
You should get 90 miles at 4.0 mi/kwh. This will likely occur by driving at 63 MPH (indicated=60 MPH actual) on flat dry pavement w no wind at about 70 degree F.

You wont have any luck talking to the dealer about gids, Ah capacity or any measurment except miles of range.

 

[DaveEV]

My question is: what kind of range am I looking for? I know the answer varies based on driving style, elevation, type of road, temp, etc. But what is the range of the mileage I should look for? I saw a post earlier in this thread of someone who went 114 miles on a charge.

If you want to produce results that are the most repeatable, see these threads for guidelines based on TonyWilliam's earlier testing.

Note that for most accurate testing you will drive the car until turtle mode actually engages. Have a tow truck ready or hope you get real lucky when you run out and happen to hit turtle very close to a charging station.

Phoenix Range Test Results, September 15, 2012
2012 / 2013 LEAF Range Test San Diego Mar 8, 2013

Basic procedure:

60 mph ground speed on as flat a road as possible (confirm with GPS)
HVAC off
Calm winds
Mild temperatures (70-80F)
Front windows no more than very slightly cracked open
Reset trip/efficiency meter at beginning of test and document trip meter, efficiency meter, GID counts at beginning and end of test. Bonus points for documenting readings at LBW and VLBW.
Tires inflated to 36PSI cold.

A new LEAF will go around 84 miles += a few percent depending on how close you reproduce those.

 

[crabasa]

Well, I couldn't replicate the pristine conditions above, but I did record some data on my experience going from 100% on the dash to Turtle.

Date & Time         Mileage QCs L1/L2   SOH     AHr     GIDs    Charge Display  SOC
3/23/2014 15:00:00  797     6   62      89%     58.38   253     100%            97.3%
3/26/2014 8:32:00   879     6   62      89%     58.43   26      10%             17.3%
3/26/2014 10:22:00  897     6   62      89%     58.43   5       Turtle          3.1%

Some things to consider:

• Covered 100 miles
• Very conservative driving (4.5 miles/kWh I think, not sure how to verify)
• Took place over 4 days
• Mix of highway and urban driving
• Light rain on and off the last few days
• Temps ranging from 45-60 F

 

[mkjayakumar]

You could have spared yourself all that driving. You had 253 Gids on a full charge. So that is, ((281-253)/281)*100 = 10% degradation.

 

[Berlino]

You could have spared yourself all that driving. You had 253 Gids on a full charge. So that is, ((281-253)/281)*100 = 10% degradation.

I used to have as low as 262 Gids on a full charge, but now I have 284. Am I to believe that I had 6.8% degradation at one point, but since then a Li-Ion fairy has come and miraculously refurbished the pack?

If the answer is no, there may be more to calculating degradation than a simply looking at Gids, so range tests have their place.