padamson1 said:
Since Nissan is now saying 20% loss after 5yrs (down from 30% over 8yrs), losing one bar after 26k miles doesn't seem all that far off because practically every charge was to 100%. Given that the LEAF is 73mi range per 100% charge car, 13k mi/year would be the expected annual mileage, thus 10% capacity loss should be expected after more than two years worth of driving the car. If one bar really is 20% (which has been the interpretation here on MNL), then this represents twice the normal capacity loss.
I'm not sure I follow your logic. First of all, this car was driven an annuallized mileage of about 16,300 miles, which is not too much above the average. Secondly, your calculation implies that mileage is the primary factor here. Since there are other LEAFs north of 40,000 miles with less than 10% battery capacity loss, I will argue that it is not the major contributor here. As you say, charging to 100% is likely the major culprit here. Or, more precisely, I suspect it is the time spent at 100% SOC combined with temperature that matters most. But it is hard to say for sure.
To me, this is the most disturbing report that I have seen because the battery in this LEAF probably stays year around close to the 72F temperature that the Volt's TMS targets. If the battery loses 15% of its capacity in 1.625 years under that temperature environment, then it implies that the charging regime chosen by Nissan must be extremely damaging to the battery. It will be interesting to see if the Volt's strategy of avoiding the higher SOCs really makes a difference. I suspect it will.
padamson1 said:
Perhaps 80% charge level should be labelled for 'normal' battery life instead of 'longer' battery life. :?
More likely the 100% mode should be relabeled "Very Short Battery Life Mode".