Valdemar said:
Are you saying this was a defective batch?
No, What I'm saying is that this is a design flaw and appears to affect all the 30 KWH batteries. They aren't heat tolerant enough for the South and Southwest U.S. Whether we see some early failures in the Midwestern states is still uncertain but we do have reports of some loss of capacity already. If you live in an area with short summers or highs of less than 90 degrees, there's a likelihood that your battery will last significantly longer. On the other hand, there's an eight year, 100k warranty period so Nissan has increased exposure. There could be a high failure rate toward the end of the warranty period even in areas with mild climates. We are two years into an eight year warranty period and we have already started to see warranty failures. A lot of the 24KWh packs made it to the 5 year mark without triggering the warranty. They are still degraded, just not badly enough to trigger a replacement.
Even if your battery does last for 100,000 miles, odds are that it will still be significantly degraded (70% or less) at that point. For most people that's not really acceptable. Even Nissan has said that the battery is only expected to retain 80% at 100k. It appears that 60-65% is the warranty trigger point. Will you be happy with with a 20KWH car?