Discuss data from the LEAF Battery app, and Comparisons

[Evoforce]

Don't give yet! Last day is this coming Friday right? Like I mentioned before, could you use an inverter and use your Nissan Powerwall to power up 120 volt things in your home? If you are hitting 181GIDs you are deadly close. I'm pulling for ya!

 

[kolmstead]

178 GIDs this morning. First time I've ever seen it in the 170s. Ahr and Hx unchanged at 42.46 and 43.54%. I bought the car on Jan 15, so five year warranty probably ends close of business on 14th.

-Karl

 

[mwalsh]

178 GIDs this morning. First time I've ever seen it in the 170s. Ahr and Hx unchanged at 42.46 and 43.54%. I bought the car on Jan 15, so five year warranty probably ends close of business on 14th.

-Karl

Karl, I have to think you're absolutely on the cusp of loosing.

Inconvenient, I know, but you really need to consider taking the time to drive the living heck out of it this week, going through multiple charge cycles each day. And don't forget to drive hard! You must be at the point where you can completely exhaust the pack within 30 miles, so that's only a 15 mile round trip. And a full recharge can only be in the region of 3-4 hours on L2. Please consider it.

This is precisely what I did to force the issue when I thought I was running out of weather conducive to capacity loss, and you know how it worked out for me!

Edit: Ah, I see you tried this over Christmas already, and you didn't think it worked. Can I be the contrarian and suggest that the opposite is perhaps true, and it's helped contribute to your precipitous drop from 183 Gids.

 

[kolmstead]

I think you're right, Mike; every time I've done two charge/discharge cycles per day for a week my stats have improved, but a week or so later I see signs of degradation. Did I do enough driving over Christmas? We'll see. At least the battery seems to be responding again. It has been stuck at 183 GIDs for about three months.

I get about 40 miles if I drive at the speed limit in the mountains now, and it takes about 4 hours to recharge. 14 kWhr storage, at 3.3 kW recharge rate... so I can comfortably do two discharges per day. Three would probably require night driving, which I hate doing when I'm running the car down to empty. I haven't gotten stuck on the highway yet, and don't want it to happen when it's dark and cold out. I do manage to scare myself two or three times a week. There have been several recent "heat off, keep it at 35 mph" limps home on the 55 mph highway. I now have more than enough experience driving in turtle mode. You can get the lowest cell pairs down to about 2.972 Volts before the contactor opens...

Gotta look at economics, also. I could have taken a week or two off just to drive the car, but the lost wages would have just about paid for a new battery. In order to exercise the car over Christmas, I trailered the car the 56 miles to Lake Isabella. I still regret that I didn't do the same over the 4th of July and Labor Day. Based on Ahr readings back then, I didn't see the need.


-Karl

 

[mwalsh]

^ Well it'll be a bit of a hail-Mary, but if you go down just outside of warranty you could petition Nissan at the executive level. There is precedent for that being a successful endeavor. Either way, know that I'm still pulling for you!

Edit: Perhaps our focus on AHr this whole time has been a mistake. I was only tracking Gids as an afterthought, but you can see in this post that I must have lost bar 9 at or around 177 Gids, after noting that I had "stuck" at 184 Gids for the longest time and then 181 Gids for longer than I would have liked:

http://www.mynissanleaf.com/viewtopic.php?f=44&t=12789&p=446853&hilit=177+gids#p446853

Edit 2: Turns out that both nyleaf and ahagge also lost bar 9 at 177 Gids; occ lost bar 9 at 178 Gids; highdesertdriver at 176 Gids. I'll look for more, but I already see a pattern developing! And one that bodes well for you, Karl.

Turbo3 wrote:
What is your 100% full charge Gid number on your pack to be replaced?


Still 177 Gids.

The one thing I've always found weird about my pack is that Gids have sort of been stationary (or nearly stationary) until the weren't. I was at around 184 Gids for the longest time. Then all of a sudden I was at like 181, and now I'm at 177. The next time I notice they've dropped I'll probably be at something like 173.

I guess what I'm saying is they don't track with AHr losses. That might be normal...or not, I don't know.

 

[kolmstead]

Yes, I also believe that GIDs may be a better indicator than all the fancy stuff we've been focused on. Turbo3's understated remarks got me thinking.... but I seem to recall that some folks have reported 9th bar loss while still seeing 100% charge GID readings in mid-180s.

-Karl

 

[fooljoe]

Yeah I was still getting GIDs in the 180s when bar 9 dropped. Wow Karl - I can't believe that thing's still hanging on for you! :shock:

Assuming a miracle doesn't happen in the next few days, I'd take it in anyway before the warranty expires just to have the complaint documented, and whatever you do don't give up without a fight!

 

[mwalsh]

Yes, I also believe that GIDs may be a better indicator than all the fancy stuff we've been focused on. Turbo3's understated remarks got me thinking.... but I seem to recall that some folks have reported 9th bar loss while still seeing 100% charge GID readings in mid-180s.

-Karl

I haven't found any that high (yet), but I did find 4 at 180 Gids; one for 181 Gids (I suggested myself that 181 Gids might be a magic number at one point); and one who reported 179 Gids a couple of months before the loss but then didn't report Gids again AT the loss. So, again, it's kinda all over the place.

But I gotta feel that if you can just shed one more Gid between now and in time to report the loss to Nissan before COB on Thursday...

 

[fooljoe]

Vin ends in 4613. No charging in between morning and loss of the bar, although I did sneak a charge in at lunch before getting the Leafstat screenshot. Max Gids I've been getting lately is 184. Taking it in to the dealer tomorrow.

I'm sure yours will drop soon, kolmstead. Maybe it was somehow triggered by the recent cooler temps? I did see 5 temp bars this morning after being at at least 6 pretty much all summer.

I reported getting 184 around the time I lost my bar - can't say how exact that is though as I paid a lot more attention to Ah than GIDs after a full charge (since "full" is so highly variable.)

Dug around a bit and saw Stanton reported 183 GIDs, gbshaun reported 185... Basically Karl's way overdue by any measure except for the only one that counts to Nissan.

 

[kolmstead]

GIDs is a tricky parameter to monitor, which is why we've tended to focus on Ahr. All it takes to get a low 100% GID reading is to run the battery down a little and top it off. I guarantee that the new GID reading will be considerably lower than what you'd get if you recharged from 50% or lower. I got all excited once this fall when I saw a 175 after topping off. Next day, after normal discharge and recharge, back up to 185 GIDs.

In addition, almost everyone loses a few GIDs in the fall, and regains them when the battery warms back up in the spring. I'm reasonably comfortable with what I'm seeing now; my morning battery temps have been in the mid-fifties for about a month. And virtually all my recharges are from VLBW or below. That's why I mentioned the 100% GID readings dropping; up until last week they had been rock solid at 183 for months.

-Karl

 

[kolmstead]

Back to 181 GIDs this morning. Damn!

Something odd happened last two nights. The car turtled between 0.8 and 0.9 kWh remaining.. around 12 GIDs. That's way high. I normally see turtle at 0.4 kWh. I was still out on the highway both times, thinking I had plenty of reserve. Limped home ok both times. Going to have to get a bit more conservative!

 

[mwalsh]

Back to 181 GIDs this morning. Damn!

Something odd happened last two nights. The car turtled between 0.8 and 0.9 kWh remaining.. around 12 GIDs. That's way high. I normally see turtle at 0.4 kWh. I was still out on the highway both times, thinking I had plenty of reserve. Limped home ok both times. Going to have to get a bit more conservative!

I'll have to look back, but being unexpectedly caught short happened the day before I lost bar 9!

Edit: Here it is:

http://www.mynissanleaf.com/viewtopic.php?f=44&t=12789&p=441007#p441007

If it was me I think I'd be driving round the clock between now and Thursday, sleeping/napping while charging back up for the next go round.

 

[Evoforce]

Yep, I lost mine at 180 GIDs. Keep using her! My AHr was 41.79

 

[Aussie]

Geez so close. Good luck!

 

[mwalsh]

Do or die day for Karl today - the way I see it he must loose bar 9 in time to get his car over to a Nissan dealer this afternoon and have a service order for it written up before COB, or he is out of warranty.*

Hopefully bar 9 will be gone when he starts up this morning and all will be well. Good luck Karl!

*Calling into the Nissan EV line might also work if the loss of bar 9 happened after the dealers are all closed but before midnight tonight.

 

[kolmstead]

Appreciate the thoight, Mike, but I am going back to my earlier prediction... I'll lose bar 9 in March, at 42.0 Ahr.

At least after today, I don't have to worry about it.

-Karl

 

[mwalsh]

Appreciate the thoight, Mike, but I am going back to my earlier prediction... I'll lose bar 9 in March, at 42.0 Ahr.

At least after today, I don't have to worry about it.

Well, at least keep double-checking throughout the day, just to be certain!

 

[kolmstead]

Back to 183 GIDs this morning. The car was just messing with me for the past two weeks! As soon as I saw it climb back up to 181 yesterday, I knew the game was over.

-Karl

 

[mwalsh]

Well, sadly, we knew there would be some owners would just miss out.

I've said this before, but I'm actually really surprised it hasn't been more of us - I figured it would be the majority rather than a minority.

 

[kolmstead]

We have a new class of Leafs emerging that we've never (other than opt-outs) had before... cars that no longer qualify for the battery capacity warranty. How long before somebody posts that they got a really good deal on an 8-bar 2011 and we have to break the news to them that they aren't going to get a new battery? You know it's going to happen.

-Karl