sksingh said:
To gain the maximum battery life, it appears that max charge should be 80% and should not be discharged down to more than 20%. The useful range then is 60% of battery capacity, and that is what should also be stated by all manufacturers, in addition to any other claims they may want to make.
And if not more than one QC is the norm for battery life, then the operating radius of the car would be based on that, which is 120% maximum. All the talk about having QC stations along highways seems rather futile.
Most practical use would be a daily commute that could be done with 60% capacity. That's 42 freeway miles round trip, or 60 city mile with speeds not exceeding 45mph.
My battery capacity now stands at 48.4 Ahrs or 73.8% at end of 30 month with 30k miles. Very close to losing my third bar. And my daily commute of 50 miles round trip is in danger.
I agree with a slight editing of your statement. The most practical use would be a daily commute that is 42 freeway miles round trip, or 60 city miles with speeds not exceeding 45mph.
But the rationale you stated for this is incorrect.
I agree with surfingslovak and DaveinOlyWA that the importance of staying between 20% and 80% status of charge is probably not that significant. If the time above 80% and below 20% is kept relatively short, it just doesn't make that much difference. The capacity loss is driven by time and temperature. Even DCQC doesn't make a lot of difference if done with 6 temperature bars or less, and its impact is one of a bit more time at a higher temperature, which increases the average temperature the battery is at by some modest amount.
The correct rationale is based on two things.
First most drivers do not want to be driving around below Low Battery Warning. This leaves around 17% to 20% of the 24 kWh battery capacity unavailable, even when the LEAF is new and has 100% capacity. (Yes I recognize some zealous MNL participants do drive to VLBW or occasionally to turtle a lot. I believe they're a small minority of LEAF drivers. I've only been to LBW six times in 16,000 miles. Only seen --- on the GOM once a couple miles short of DCQC station. Never seen VLBW or turtle.)
The second and most important rationale is that battery capacity steadily declines.
Even the early Nissan statement on battery capacity loss was 80% at 5 years / 60,000 miles; 70% at 10 years / 100,000 miles.
The LEAF is a 40 to 60 miles between charges vehicle based on these two rationales.
Does a lot better early on, but not over the life of the vehicle.
The sad thing is that Nissan missed it on their capacity projections. The 2011 / 2012 / 2013 / and at least some significant part of the future 2014 LEAF production run have a battery that degrades markedly faster than Nissan projected.
So sksingh, you're unfortunately having to live with a range at 30 months of use and 30,000 miles that you shouldn't have experienced until 96 months or more and 80,000 miles.
I don't know if you leased or bought. If you leased for three years and were planning to change vehicles at the end of the lease, you're experiencing impacts that you didn't expect and that Nissan isn't going to do anything about.
They have provided a modest 5 year, 60,000 mile, 66.25% capacity warranty.
If you leased, unlikely you'll get a new battery before the lease runs out.
If you bought you are fortunate that you probably will get a new (or likely at least 10 or 11 bar replacement battery) to get another couple years of use out of the vehicle.
But most LEAF purchasers are like me and will not get a battery replacement and will end up with a slightly greater than 60,000 mile vehicle with a degraded battery that Nissan didn't think would happen until 10 years / 100,000 miles.
I think we ALL have good justification to be very unhappy with the Nissan LEAF battery capacity degradation.
