Charging to 100% vs. 80%

[lawsonmitchell]

My new 2012 Leaf SL has been working out beautifully so far. My question is ... with my long commute 54 miles each way. I have been charging to 100 percent on both ends. I'm not sure the 80% charge will get me all 54 miles. Am I shortening my battery's life?

 

[KJD]

My new 2012 Leaf SL has been working out beautifully so far. My question is ... with my long commute 54 miles each way. I have been charging to 100 percent on both ends. I'm not sure the 80% charge will get me all 54 miles. Am I shortening my battery's life?

How long does the car sit with the battery at 100% ?

Use the charge timers and set "End Time" only ( Leave start time empty ). Also set the End time really close to your normal departure time and your battery will be fine.

 

[lawsonmitchell]

Never sits at 100% for more than a couple of hours a day.

 

[grommet]

Don't worry about it. Impact is minimal.

 

[KJD]

Never sits at 100% for more than a couple of hours a day.

Not a big problem then.

You might want to add city and state to your location on profile page. How many summer days are over 100 f ? That will age your battery more than anything.

If you buy a GID meter, it will tell you what the real state of charge ( SOC ) is on the battery. The Nissan bar graph is not very accurate on SOC.

 

[Weatherman]

My new 2012 Leaf SL has been working out beautifully so far. My question is ... with my long commute 54 miles each way. I have been charging to 100 percent on both ends. I'm not sure the 80% charge will get me all 54 miles. Am I shortening my battery's life?

Florida summer heat will mean you won't have much choice but to charge to 100% after a year or two. I hope you know what you got yourself into by being a high-mileage driver in a hot-summer (and warm winter) state.

 

[Stanton]

If it's not 54 miles of highway, then you should try charging to 80%
If it IS all highway...then you have my sympathies.

 

[lawsonmitchell]

OK. And thanks for all the tips.

For the record the summer temperature in coastal Florida is typically much cooler than many parts of the country. The summertime highs very rarely exceed 95 degrees F and are more typically in the low 90s F. It's the humidity that makes it feel so damn miserable. 90 degrees at 95% HUMIDITY for almost 90 days straight can wear on one's soul. As far as I can tell humidity should not affect charging?

The trip is roughly 65% Interstate at 70 mph and the remainder on secondary roads. So far I have been averaging 4.6 miles/KwH.

Lawson

 

[Stanton]

The trip is roughly 65% Interstate at 70 mph and the remainder on secondary roads. So far I have been averaging 4.6 miles/KwH.

Since you seem committed to making this work, here's a couple of suggestions:
1) keep your highway speed down to 60 mph; it makes more difference than you think
2) keep your eye on the "temperature bars" (on the left side of the dash) on super-hot days and limit charging (when possible) when you see 7TB; you may see 6TB in the AM and 7TB in the PM when the temps near 100 (humidity isn't really an issue)

I do this in Texas and it seems to help a lot (check my sig). Specifically, I put a shop fan in my garage that I use on 7TB days which helps along with late night/early morning (end-only timer) charging. A little bit of extra care goes a long way.

 

[Weatherman]

I'm not sure why this is the case, but there seems to be a perception among many Florida residents that we are immune from the battery degradation problems Texas and Arizona LEAF owners are experiencing just because we rarely see high temperatures above 100F.

It isn't the extreme high temperatures that are going to kill our LEAF's batteries, it's the persistent warm temperatures.

Degradation doesn't just shut off at temperatures below 80F. It merely slows down. So, while other parts of the country are enjoying temperatures in the 40s, 50s and 60s (or even colder) during the fall, winter and spring, Florida is still basking in the 70s and 80s.

We've already had one South Florida LEAF owner report a one-bar loss at only a little over one year and 16,000 miles. If you are a Florida resident, and you are racking up 20,000+ miles a year, your battery is going to degrade very quickly no matter what you do.

 

[dgpcolorado]

OK. And thanks for all the tips.

For the record the summer temperature in coastal Florida is typically much cooler than many parts of the country. The summertime highs very rarely exceed 95 degrees F and are more typically in the low 90s F. It's the humidity that makes it feel so damn miserable. 90 degrees at 95% HUMIDITY for almost 90 days straight can wear on one's soul. As far as I can tell humidity should not affect charging?

The trip is roughly 65% Interstate at 70 mph and the remainder on secondary roads. So far I have been averaging 4.6 miles/KwH.

Lawson

4.6 miles per kWh is quite good for that speed (are you resetting it after each trip?). You should be able to make it easily with an 80% charge on each end. 54 miles / 4.6 miles/kWh = 11.7 kWh. That is just more than half the usable 21 kWh of energy in a new battery pack. If you can keep that good mileage efficiency you should be able to handle battery degradation for some years to come.

You ought to see lower mileage in rain and in wind. The humidity in Florida increases mileage because humid air is less dense than dry air at the same temperature. Humidity plus warm temperatures are why a LEAF can generally beat the EPA range by substantial margins in Florida.