Also,
For those that already own a Leaf, there are a few things you can do to minimize battery capacity loss:
- Keep the state of charge in the 30-40% range (on the Gid meter) as much of the time as reasonably possible. This roughly corresponds to 3-4 fuel bars for a new Leaf. Charge to 80% or 100% right before you need to make a longer drive.
- Shallower cycling (DOD) of the battery pack when possible. For example, two cycles of 60% to 30% SOC rather than one cycle of 90% to 30% should be better for the battery pack.
- Avoid parking in the sun when possible. Solar loading may increase the yearly average battery temperature by 1.3-3.1 degrees Celsius for a vehicle always parked in the sun (based on studies of the Prius, Media:HEV_Battery_Life.pdf)
- Drive and accelerate more slowly and more efficiently. This will have two effects:
- Minimizing waste heat (estimated to be 1% at 10 KW power draw, 3% at 30 KW power draw)
- Reduced cycling of the battery for the same number of miles driven, which will reduce cycling losses
On October 4, 2012 Nissan released a video of Chelsea Sexton interviewing Andy Palmer, Nissan executive vice president of product planning. The following points were made:
- To establish degradation expectations, Nissan used as a norm the LA4 driving cycle and 12,500 miles per year
- For that norm, expected degradation is 80% at 5 years and 70% at 10 years
- There are 4 variables that affect whether that mean will be achieved:
- The speed and gradient on which you drive--highway speed will have a greater degradation
- Frequent fast charging (recommend no more than one QC per day)
- Miles driven per year
- Temperature
- Arizona Leafs are averaging 7,500 miles per year (but this was not known prior to sale of the Leaf in Arizona, it is post hoc information)
- Based on 7,500 miles per year, the Arizona Leafs are projected to retain 76% of capacity after 5 years (translation: in order to have "only" 24% capacity loss at 5 years, Arizona Leafs are limited to driving 37,500 miles, and only driving the less demanding LA04 cycle)
- Capacity bar meter reads "pessimistically"
- Leaf has 95% satisfaction rate, the highest of any car Nissan sells
- 2013 model year will have evolutionary, not revolutionary changes; the gauge accuracy is addressed
- Nissan is looking at options to address the complaints about pressing "OK" on the Navigation screen each time Leaf is turned on
http://www.electricvehiclewiki.com/Battery_Capacity_Loss#Nissan.27s_Responses_and_Actions
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