14.4 kWh battery kappa max after 6 yr 9 months? [2014]

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wedona

New member
Joined
Jul 7, 2021
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4
How many miles can be expected in moderate weather 50-70F, 65 mph highway driving?

Is this on track to get a warranty replacement by 8 years?

Is this high or low for its age?
 
Assuming an efficiency of 4 mi/kWh at 65 mph, full range would be 57 miles. The average efficiency of our 2014 BEV is 5.2 mi/kWh, but that's in mostly suburban and urban driving at much slower speeds at 65º-90º.

Our 2014 BEV is almost the same age as yours but has been driven less than 12k miles, partly because it has been stored 4 times from 3 to 9 months each, for a total of 2 years. Nevertheless, its Batt. Kapa. max value is only ~15 kWh. The im3 app indicates that its usable capacity has dropped by 23%.

Usable capacity must be less than 13.3 kWh to qualify for a warranty replacement. It seems unlikely that the usable capacity of your or our battery pack would drop that far in the remaining months of warranty coverage.

There seems to be something about 60 Ah battery cells that results in many, but certainly not all of them degrading much more rapidly than 94 Ah or 120 Ah cells. The 14.4 kWh Batt. Kapa. max of your battery pack is certainly within the wide range of Batt. Kapa. max values of 60 Ah battery packs. Because of this, I never advise that anyone buy a 60 Ah i3 unless its usable capacity has remained relatively high over many miles.
 
Thanks, this is helpful.

I found another 2014 for sale that has 14.5 kWh. So this seems to be what's expected.

In contrast, the 2018 94ah I looked at was at 29.5 kWh.
 
wedona said:
In contrast, the 2018 94ah I looked at was at 29.5 kWh.
That's essentially its usable capacity when new. 94 Ah and 120 Ah battery packs haven't been degrading noticeably.
 
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