Can I lose a capacity bar over Texas winter/spring

Guys and Gals,

I'm looking to buy my first leaf. I've found a 2011 SL that looks pretty good cosmetically and is very attractively priced but the battery is hammered and only has 9 capacity bars remaining. I bought an OBD dongle and hooked it up with leaf spy...it shows AHr = 42.38, SOH = 64% and Hx = 43.4%.

From what I read on the forum this battery is right at the tipping point for loss of the 4th capacity bar and qualifying for a battery replacement. Other forumites report that they have lost the 4th capacity bar with the above stats (or even slightly higher AHr).

Carfax shows that the vehicle was registered in May 2011 (I'm going to call the EV hotline on Monday and confirm the warranty expiry date). It's got plenty of miles left. So my question for the collective wisdom of the forum...do you think I can degrade the battery enough over Texas winter and spring to drop my final capacity bar?

Things to note:
-Free L2 charging at my apartment (if I need to implement power-wasting strategies)
-There is a CHAdeMO charger at Walgreens around the corner from where I live. I'm happy to pay to degrade the battery if necessary.
-Vehicle has spent most of it's life in LA.
-I'm in Texas.
-This leaf has been sitting on the lot for around 30 days. It was at 85% SOC when I test drove it, so I assume it's been sitting with a high SOC possibly for a while.

I would really appreciate if you can share your experiences with real world battery degradation over the cooler months.

If the capacity warranty is valid through the end of May, there is a reasonable chance that it will lose the 4th bar in time to qualify because it looks like the capacity is close to the threshold. I lost bars 12 and 11 close together during the second summer and bars 10 and 9 close together during the following summer on my 2011. Although capacity continued to drop during cooler temperatures, all of my bar losses happened during summer.

Gerry

The battery stats on the car you're considering are virtually identical to mine. Worst case, the ninth bar should drop this coming spring. Not many cars lose a capacity bar during the winter. My Leaf held on to its tenth bar all last winter, despite very low Ahr readings. It finally lost the bar this past March, at 46.01 Ahr. I'm beginning to think that it may exhibit the same behavior this winter, and drop the ninth bar in March at 42.01 Ahr.

Nissan's battery capacity warranty states that it is void if the battery shows signs of deliberate abuse. Keep in mind that the car records information about how it is used. Subjecting the battery to extreme temperatures for prolonged periods (without being driven) is abuse. Nissan specifically states that prolonged storage in temperatures over 125 F is bad. However, driving the car hard and using QC is well within the limits of normal usage. You can decide how you drive the car. Nissan has been known to read this forum, so bragging here about how badly you abused the battery is... stupid.

As you've noted, you have access to the best tool to speed up loss of the ninth bar.... the quick charger. You'll need two other things to do the job properly. First of all, the time to run the car's battery down two or three times in a day. Each drive will last roughly 50 miles. Then the car will spend 30 minutes or so recharging, so you're looking at five or six hours total. Blows a big hole in a day. The other requirement is a road where you can drive fast (or better yet, uphill). In order to heat up the battery, you need to get your consumption up in the 40 kW region for most of the run. Steep downhill is okay also; regeneration heats up the battery, and then you can use that energy again driving back up the hill. Run the heater as high as you can stand it to add to the battery's load.

Try and select a standard route. That way you'll know how many kWh it takes to get home. Run the car down to VLBW (24 GIDs) or below. Try to end up with no more than 1.0 kWh remaining. Turtle will happen around 0.5 kWh... anywhere from 6 to 10 GIDs. You don't need to push it that hard. Be conservative if you try one of these "drives to nowhere". Better to arrive home with too much charge left than to strand yourself.

Each drive/recharge cycle should heat the battery up roughly thirty degrees, depending on ambient conditions. So starting out with a battery temp of 50 F, you should see at least 80 after the first drive/recharge, then 110, and finally 140 F, which is well into the red temperature bar region. Recharge immediately.

Don't be surprised if the battery stats actually improve for a while. In the short term, running the battery almost to exhaustion and performing a QC often improves Ahr. But any time the battery is over 85 F, degradation is occurring. And over 100 F, it is proceeding quickly.

Good luck with the Leaf. I really enjoy driving mine. And again, I would expect that with no help, the one you're looking at will drop the ninth bar by March or April. If it's been sitting around for a while, it might lose a bar as soon as you perform a few charge/discharge cycles.

-Karl

Thanks so much for your replies. Kolmstead your post has given me a huge amount of excellent information and I appreciate you taking the time.

The good news is I agreed to terms on the vehicle today at $8,250, down from $9k. Whilst I could have negotiated harder (given the battery condition) I'm sick of missing out (and catching the train to work!). I pick it up next Monday. Assuming I can qualify for the replacement battery I think this will be a reasonable deal.

I was planning to take a few good road trips with it anyway, so it sounds like my plans will actually be along the lines of your suggestions. I wasn't planning any funny business (I'm guessing you were inferring it sitting in a heated garage, which I don't have). Not too many mountains around here in north Texas, I think I'd be hard pressed to find a hill!

Looking forward to taking a more active part in the forum!

Cheers

I think you are real close. I lost my 4th bar at 41.79 AHr and 63% SOH and 180 GIDs. As you say, many have lost it at higher numbers than mine. May, might be a squeaker, but I think you can make it. Keep in mind, Nissan has been replacing these batteries rather than repairing them for people in your proposed ownership position, but as a business practice and it is not a legal obligation. They could change their position at any time. Only those who were mailed packets from the court in 2013 are guaranteed a replacement. So far... things look like they would go in your favor. It is a slight gamble on both fronts. I went from 71% SOH to 63% SOH in 4.5 months (July- Nov.) in AZ.

Picked it up last night after work. After 1 1/2 battery cycles the AHr has dropped from 42.38 to 42.30 and Hx 43.4 to 43.27 (whatever Hx means). Looks like it won't take long!

I noticed regenerative breaking doesn't start kicking in over level 1 until the battery starts getting down, and it doesn't start regenning at high levels until the battery is quite low (25%). Is this normal for degraded batteries?

Yes, when the battery temperature is low (less than 80 degrees or so), regeneration is very limited. Below 50 degrees, it is virtually nonexistent. After the car hits VLBW (24 GIDs), you get full regeneration.

I ran my car well into turtle last night... 4 GIDs remaining... about 0.4 kWh... and it still indicates 42.38 Ahr. It's been gradually rising for about three weeks, as battery cools off. 100% charge yields 183 GIDs, which hasn't changed for several months. Degradation during the winter is virtually zero.

-Karl

When's your battery warranty valid to Karl?

Depends on whether Nissan uses purchase date (Dec. 29, 2010) or the date I picked it up (Jan 15, 2011). Either way, the end (of warranty) is very near! I've just about given up hope.

-Karl

Ah geez, so close! Have you got QC? Where are you located?

Mine's dropped to 42.23 and Hx 43.17 today after another 1/2 battery cycle. I think you predicted it could fall through the floor. At this rate it'll be to 8 bars in a couple of weeks. But I don't want to jinx myself!

kolmstead said:

Depends on whether Nissan uses purchase date (Dec. 29, 2010) or the date I picked it up (Jan 15, 2011). Either way, the end (of warranty) is very near! I've just about given up hope.

-Karl

Click to expand...

Pretty sure it is when you took possession. You must have some repair orders that I think refer to start of warranty on them. Time for you to visit some distant relatives this Christmas season. Golly! So shockingly close. Come on, you can get there!

AHr bounced back up to 42.3 and Hx back up to 43.28%. That's annoying!