Weak cells (just got Leaf spy pro for apple)

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

JonO

Member
Joined
Dec 7, 2013
Messages
16
Location
Manitoba, Canada
The last 2 times I went to LBW some weak cells showed up.
Cells 1 and 48 were consistent and a couple others also registered as weak.
The first instance was min/avg/max = 3.513 3.621 3.664 (151 mv) cells 1 and 48
Then as I watched it starting to charge, Level 2: min/max/avg = 3.618 3.709 3.737 (119 mv) weak cells 1, 37, 44, 96
then at full charge the pack avg was 4.060 (23 mv)
Next time, not quite so low SOC with about 3.655 avg (38 mv) pretty much the same cells 1, 47, 48, 96

So is this anything that warranty might address? There are no error codes showing related to the battery.

This is on a 2011 that spent the first 2 1/2 years in Vancouver, but the last year and half north of Winnipeg, mb where we've seen some extremely cold weather. I do keep it in a garage and it is almost always plugged in when temps get below 10 deg C. Only 12000 kms on it now.
 
JonO said:
...
Next time, not quite so low SOC with about 3.655 avg (38 mv) pretty much the same cells 1, 47, 48, 96

So is this anything that warranty might address? There are no error codes showing related to the battery.

...
This is a pretty good short thread from August 2014.

http://www.mynissanleaf.com/viewtopic.php?f=9&t=17676&start=10#p383922" onclick="window.open(this.href);return false;

The service manual says the cell pairs that show bad should be replaced.
But I have not read any reports on MNL of this having been done other than a few cell pairs that were horribly bad.

As discussed in the earlier thread opening the pack just to replace a few weak cells is probably not a great thing to do.
But if you were near the end of the 8 year /100,000 mile warranty end and you had ten or 12 weak maybe worth trying.
At that point the cost might be getting closer to cost to just replace the whole pack.
Some cost share between Nissan and the customer and replace the whole pack would be smarter.

I would note that I have run CVLI all the way down to turtle, and the worse the cell voltage differential the less cell pairs show as "bad".
I have eight "bad" cells soon after starting the test.
But once cell differential is more than 100 mv all the cells show up as good.
Strange.
 
Back
Top