Losing two fuel bars at once

[Pipcecil]

This has happened to me a few times, and seems more prevelant as I loose more capacity. When I am driving, either on freeway or a slow local street (it doesn't matter), I will loose two fuel bars at once. I have only seen it on bars 2&3 or 3&4. Nothing extra is going on - no acceleration, no start/stoping abruptly, etc. I am usually just crusing at a stead speed, usually on cruise control. The odd part about it the loss bars don't reflect (or shouldn't reflect) my usage.

It happened again last night - a full car doing a 6 mile trip (down 3 capacity bars for reference) and while I expected to loose one, maybe two (stupid capacity loss), loosing both 2&3 at the same time was a shocker. Six miles of local driving shouldn't result in 3 fuel bars lost - thats 2 miles per fuel bar over streets that are 45 mph (and with no climate control).

Does anyone know why the car will drop two bars at once? I know the issue with the "recalibration" when you turn off your car and then turn it back on - the capacity recalibration is different from startup versus driving. But I didn't stop my car nor turn it off (drive-through). I thought it was the system recalibrating itself while driving but to miss enough capacity to loose 2 bars at once seems far fetched. Any ideas?

 

[Deleted member 9549]

Could you really be losing charge that quickly? How much capacity do you have left with the Leaf app?
I haven't heard of it with cars, but with laptops I've had, once the battery gets worn out it will report high SOC until it suddenly says its empty.
How old is your car?

 

[adric22]

I'm going to make a guess here. I suspect the car calculates your fuel bars based on two criteria. The first is voltage of the main pack under load and the second is how many amp-hours you've already used which is measured by a current sensor. My guess is that the car had to re-calibrate after noticing the voltage was lower than expected. This could be because your battery has lost more capacity than your computer has figured out yet. Could also be a bad cell.

 

[GeekEV]

I have observed that behavior as well, but things go back to normal after that.

 

[Nubo]

Weird. When was the last time you ran a "balancing charge"? I.e, charge to 100% and remain plugged-in for an additional 4 hours?

I've never noticed a sudden 2-bar drop, but did notice a much-quicker-than-normal decline in the guess-o-meter predictions at the low end of SOC when I hadn't done a balancing charge for a long time (months).

 

[dhanson865]

well he is in Texas, that might be a 4 bar loser in the making.

wiki shows it as a 2 bar loser
bar 2 Aug 16, 2012 Pipcecil AKA Nathan Drozd Midlothian, TX 23652 miles 14 months 5/11 04094 Aug 16,2012
bar 1 Jun 17, 2012 Pipcecil AKA Nathan Drozd Midlothian, TX 20200 miles 12 months 5/11 04094 Jul 20,2012

edit: http://www.mynissanleaf.com/viewtopic.php?f=30&t=8802&p=324632#p324632" onclick="window.open(this.href);return false;

"Lost my third capacity bar today: 2 years 3 months; 44,733 miles"


now in as 3 bar loser

#22 Sep 11, 2013 Pipcecil AKA Nathan Drozd Midlothian, TX 44,733 miles 27 months 5/11 04094 Aug 16,2012 900-8070


looks like the wiki is falling behind

 

[RegGuheert]

Just posting to say I've never lost two bars at once, though recently it did seem to be playing "catch up" in the bottom half of the bars and they were disappearing rather quickly.

My guess on this issue is that the LEAF wants to be at one charge bar before giving the LBW. Since LBW is mapped to a particular amount of remaining energy rather than a particular SOC, with a degraded battery it may feel that it must immediately display only one bar to get ready for LBW. (Bars should be mapped to a SOC, so LBW would come on with more and more bars as the battery degrades.)

looks like the wiki is falling behind

It was bound to happen as more and more LEAFs lose bars. 2 Fast 2 Furious!

 

[Pipcecil]

yea its a 2011, had it 2 years 4 months and down three capacity bars. I expected less miles per bar as the system recalibrates how much energy is per bar when a capacity bar is loss, but I still can't fathom the computer being that much off to say "oops...I ment to take that last bar away a few miles ago, guess I need to correct it!" It happens infrequently, but enough that i noticed it. Most of the time I thought I was just delusional until last sunday when I actually saw both drop simultaneously.

Also for more investigational help, my cells should be balanced - I always charge to 100% since my range is too poor under 80% (current range is in the upper 50's). It could be a bad cell, but I had my battery check ~4 months ago and have not seen a huge drop in range all at once from a bad cell. Unfortunately I can't remember if there was a 2 fuel bar loss at once before I got my last battery check. I want to say its only happened since I lost the third capacity bar.

Unfortunately, I don't have the results from the android app - never bothered to get the connector for it and feel depressed at my battery degridation. I have had it checked before this past summer and it was at 74%, and that was before my third capacity bar loss.