Best charging strategy?

I know there's a ton of threads on this topic, but I still have some questions regarding my personal situation.

Driving from home to work uses about 65% of my charge. I plug in to a level 2 charger in an above ground parking garage. Should I wait a while for the battery to cool before starting to charge? Is the rising ambient temperature likely to negate the benefits of waiting? I leave home with 80% charge and arrive at about 15% charge, so is it more important to plug it in immediately to raise the low SOC? Would it be better to leave home at 95% so I could arrive with 30%? Is it important to have it off the charger for a while before driving?

Thanks for the help.

I'll take a stab at this, even though I'm no expert.

First, it would help to know what part of the country you're in, which is displayed below your name if and when you add it to your profile. Also, add what model year LEAF you have, perhaps in your signature or the question itself, because that sometimes makes a difference in "best practices". Below I assume you have a 2014 or '15, although you could be a new member who bought a used 2011, '12 or '13.

Then, unless you're in a very hot climate (esp. with an 2011-14 model year), I think you're over-thinking and over-worrying about the heat issue. Level 2, even at 30 amps, should pose no heat problems to the battery or on-board charger. Worrying about leaving home with 80 or 95% is equally and essentially inconsequential. That being said, if charging is free at work, I'd leave home with 80% and at work I'd time it to hit 100% full just before I was scheduled to leave each day. (Why not maximize their contribution? )

Finally, there is no downside to, or reason to worry about, unplugging and driving away the very next minute. Maybe it would be advisable when quick charging, but even then I doubt it -- unless your battery temp is, say, 9 or more bars. I always drive away right after quick-charging.

And finally+1, all this is "extra-true" if you're leasing. As others here have said, just relax and drive the car: you'll enjoy it that much more.

What mbender wrote, with two clarifications: if you just hit six (or seven) battery temp bars as you arrive at work, a one hour cool-down might not be a bad idea. Five bars and you're Golden - don't worry about plugging right in. And while from your perspective driving a leased car without a care makes sense (unless you might buy it as the lease ends, or extend the lease), why not improve the quality of the used Leafs available to others? Don't obsess over it, just do what you easily can to spare the car.

What if your wife calls 4 hours after you get to work and tells you the kid is sick? Get that sucker charged, so you can get home if you need to.

bguisti said:

I know there's a ton of threads on this topic, but I still have some questions regarding my personal situation.

Driving from home to work uses about 65% of my charge. I plug in to a level 2 charger in an above ground parking garage. Should I wait a while for the battery to cool before starting to charge? Is the rising ambient temperature likely to negate the benefits of waiting? I leave home with 80% charge and arrive at about 15% charge, so is it more important to plug it in immediately to raise the low SOC? Would it be better to leave home at 95% so I could arrive with 30%? Is it important to have it off the charger for a while before driving?

Thanks for the help.

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without knowing your location I can only generalize. no clue as to the distance so I say charge to full at home setting it to finish a few hours before you leave in the morning and then plug in immediately when you get to work and charge back up to full again

johnrhansen said:

What if your wife calls 4 hours after you get to work and tells you the kid is sick? Get that sucker charged, so you can get home if you need to.

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+1 - I've been bitten once by trying to "optimize" my charging too much. Found myself needing to make a run that was too far for my comfort, but at least I made it... Anyway, trying to time your charges for some magical solution that will add a tiny and theoretical amount to your battery life just isn't likely to be worth it unless you just enjoy the game of it all. At least that's the opinion I'm quickly forming...

mbender said:

First, it would help to know what part of the country you're in, which is displayed below your name if and when you add it to your profile. Also, add what model year LEAF you have, perhaps in your signature or the question itself, because that sometimes makes a difference in "best practices". Below I assume you have a 2014 or '15, although you could be a new member who bought a used 2011, '12 or '13.

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Sorry about that, I'll get that info added to my profile. I did buy a used 2011 with 24,000 miles on it. The first owner lived in the Bay Area and the battery still charges to 12 bars. I live in Northern Nevada (Reno area), so it is often in the high 90's or low 100's during July and August. I'm a teacher, so fortunately my driving is significantly reduced during the summer.

My commute is 37 miles one way of mostly freeway driving. Charging at work is free. I'm usually at six temperature bars when I get to work.

I'm hoping this car will get me to work for at least five more years, so I'm comfortable with a little obsessing. One more question: during those hot summer months would it be worth it to park the car outside my garage at home for the night? It usually cools down to 65 or 70 even when the high is 100 during the day.

bguisti said:

mbender said:

First, it would help to know what part of the country you're in, which is displayed below your name if and when you add it to your profile. Also, add what model year LEAF you have, perhaps in your signature or the question itself, because that sometimes makes a difference in "best practices". Below I assume you have a 2014 or '15, although you could be a new member who bought a used 2011, '12 or '13.

Click to expand...

Sorry about that, I'll get that info added to my profile. I did buy a used 2011 with 24,000 miles on it. The first owner lived in the Bay Area and the battery still charges to 12 bars. I live in Northern Nevada (Reno area), so it is often in the high 90's or low 100's during July and August. I'm a teacher, so fortunately my driving is significantly reduced during the summer.

My commute is 37 miles one way of mostly freeway driving. Charging at work is free. I'm usually at six temperature bars when I get to work.

I'm hoping this car will get me to work for at least five more years, so I'm comfortable with a little obsessing. One more question: during those hot summer months would it be worth it to park the car outside my garage at home for the night? It usually cools down to 65 or 70 even when the high is 100 during the day.

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Parking outside should be cooler than your garage. Just be mindful of the hot driveway if it is paved.

bguisti said:

mbender said:

First, it would help to know what part of the country you're in, which is displayed below your name if and when you add it to your profile. Also, add what model year LEAF you have, perhaps in your signature or the question itself, because that sometimes makes a difference in "best practices". Below I assume you have a 2014 or '15, although you could be a new member who bought a used 2011, '12 or '13.

Click to expand...

Sorry about that, I'll get that info added to my profile. I did buy a used 2011 with 24,000 miles on it. The first owner lived in the Bay Area and the battery still charges to 12 bars. I live in Northern Nevada (Reno area), so it is often in the high 90's or low 100's during July and August. I'm a teacher, so fortunately my driving is significantly reduced during the summer.

My commute is 37 miles one way of mostly freeway driving. Charging at work is free. I'm usually at six temperature bars when I get to work.

I'm hoping this car will get me to work for at least five more years, so I'm comfortable with a little obsessing. One more question: during those hot summer months would it be worth it to park the car outside my garage at home for the night? It usually cools down to 65 or 70 even when the high is 100 during the day.

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Something seems a bit off with the numbers, if your commute is 37 miles one way and you lose 65% of your charge, this would suggest your range is around 55 miles for the whole 100% charge. Even with freeway driving, it seems low. And yet the car still charges to 12 bars. Are you driving 80+mph on the freeways?

The # of temperatures bars seems to be pretty crappy/near useless due to the huge ranges, overlap and unknown "correction" algorithm. See http://www.mynissanleaf.com/viewtopic.php?p=365329#p365329" onclick="window.open(this.href);return false;. It's not clear which table should really be depended on.

IIRC, I almost always see 5 or 6 temp bars ALL the time in the South Bay (part of the SF Bay Area).

cwerdna said:

The # of temperatures bars seems to be pretty crappy/near useless due to the huge ranges, overlap and unknown "correction" algorithm. See http://www.mynissanleaf.com/viewtopic.php?p=365329#p365329" onclick="window.open(this.href);return false;. It's not clear which table should really be depended on.

IIRC, I almost always see 5 or 6 temp bars ALL the time in the South Bay (part of the SF Bay Area).

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Here in Upstate NY I see five bars as the baseline in warm or mild weather, and it goes up only if the pack is pushed or the car is driven a long time. That's why I tell people to not worry about five. If six bars is the baseline in warmer areas (it isn't here in hot weather, though) then just add one. For people in my situation and similar ones, at least, the temp bars are adequate.

mgs333 said:

Something seems a bit off with the numbers, if your commute is 37 miles one way and you lose 65% of your charge, this would suggest your range is around 55 miles for the whole 100% charge. Even with freeway driving, it seems low. And yet the car still charges to 12 bars. Are you driving 80+mph on the freeways?

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I drive 65 mph. Tried 70 mph and I barely made it, tried 60 mph and it was about the same as 65. The previous owner said you could get close to 100 miles on a charge, so I was pretty disappointed with the actual range. When I was shopping around for used Leafs I saw people mention that they only get about a 55 mile range on freeway driving, but I their Leafs had 50,000+ miles and I assumed they had just degraded their battery.

I do only lose about 50% of my charge going from work to home (which scales to a range of about 75 miles), because it's slightly downhill in that direction.

I was hoping that I could make my round trip commute on a single charge so I could only charge at work, but in the end I can still make it one way and run an errand or two on a charge, so it works for me.

the only time I ever go above 6 temp bars in when I am level 3 charging.

MikeinDenver said:

Parking outside should be cooler than your garage. Just be mindful of the hot driveway if it is paved.

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My only options for not parking in the garage would be paved areas. I'm guessing it would still be cooler for the battery outside overnight since I don't like to leave my garage door open all night.

cwerdna said:

The # of temperatures bars seems to be pretty crappy/near useless due to the huge ranges, overlap and unknown "correction" algorithm. See viewtopic.php?p=365329#p365329. It's not clear which table should really be depended on.

IIRC, I almost always see 5 or 6 temp bars ALL the time in the South Bay (part of the SF Bay Area).

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I agree that the temperature bars leave much to be desired. Anyone with Leaf Spy who can shed more light on topics of "garage parking vs. outdoor paved parking" or "cooldown time for the battery after driving?"

bguisti said:

I did buy a used 2011 with 24,000 miles on it. The first owner lived in the Bay Area and the battery still charges to 12 bars.

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Are you sure you still have 12 "capacity" bars? These are the small bars just to the right of the 12 long "charging" bars.

bguisti said:

mgs333 said:

Something seems a bit off with the numbers, if your commute is 37 miles one way and you lose 65% of your charge, this would suggest your range is around 55 miles for the whole 100% charge. Even with freeway driving, it seems low. And yet the car still charges to 12 bars. Are you driving 80+mph on the freeways?

Click to expand...

I drive 65 mph. Tried 70 mph and I barely made it, tried 60 mph and it was about the same as 65. The previous owner said you could get close to 100 miles on a charge, so I was pretty disappointed with the actual range. When I was shopping around for used Leafs I saw people mention that they only get about a 55 mile range on freeway driving, but I their Leafs had 50,000+ miles and I assumed they had just degraded their battery.

I do only lose about 50% of my charge going from work to home (which scales to a range of about 75 miles), because it's slightly downhill in that direction.

I was hoping that I could make my round trip commute on a single charge so I could only charge at work, but in the end I can still make it one way and run an errand or two on a charge, so it works for me.

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While these are high %'s for the distance, it is possible. If you are not coming from another eco car that tells you in your face what your instantaneous miles per whatever are, it can be unsettling to learn your "flat" terrain is really tilted.

A 12mile run of interstate here people call "flat" because we live on the base of a mountain. And it is relatively flat. However going south I can drive the entire thing at 75mph to 80mph and get 80+mpg in the Prius and lose only 5-6% on the Leaf. Going the other direction I get mid 40's in the Prius and it takes 21%-26% of the battery in the Leaf. To the naked eye, it looks pretty flat. But there is a few hundred feet in elevation difference.

The real question is does it take the same 65% for the return 37miles?

billg said:

Are you sure you still have 12 "capacity" bars? These are the small bars just to the right of the 12 long "charging" bars.

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I was unaware that the small bars represented capacity. I thought they were just there to help you judge how many long bars you were at (i.e. one down from the top is easier to see than 11 up from the bottom). But yes, there are 12 short bars.

2k1Toaster said:

While these are high %'s for the distance, it is possible. If you are not coming from another eco car that tells you in your face what your instantaneous miles per whatever are, it can be unsettling to learn your "flat" terrain is really tilted.

A 12mile run of interstate here people call "flat" because we live on the base of a mountain. And it is relatively flat. However going south I can drive the entire thing at 75mph to 80mph and get 80+mpg in the Prius and lose only 5-6% on the Leaf. Going the other direction I get mid 40's in the Prius and it takes 21%-26% of the battery in the Leaf. To the naked eye, it looks pretty flat. But there is a few hundred feet in elevation difference.

The real question is does it take the same 65% for the return 37miles?

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Yeah, before driving an EV I always figured my commute was relatively flat.

I'm not sure what you mean by the last line. It takes ~65% from home to work and ~50% from work to home.

There is a very simple summary for you to follow:

1. Charge such that your average SOC during your daily use is 50% (i.e. if you know you will use 65%, charge to 82.5%, and get home with 17.5% remaining).

2. Charge as late as you can (i.e., if you are going to charge to 82.5%, then time it so that you hit 82.5% just as you are about to leave).

2k1Toaster said:

While these are high %'s for the distance, it is possible. If you are not coming from another eco car that tells you in your face what your instantaneous miles per whatever are, it can be unsettling to learn your "flat" terrain is really tilted.

A 12mile run of interstate here people call "flat" because we live on the base of a mountain. And it is relatively flat. However going south I can drive the entire thing at 75mph to 80mph and get 80+mpg in the Prius and lose only 5-6% on the Leaf. Going the other direction I get mid 40's in the Prius and it takes 21%-26% of the battery in the Leaf. To the naked eye, it looks pretty flat. But there is a few hundred feet in elevation difference.

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Getting a little sidetracked, but I love how driving the LEAF can make one much more aware of topography. I balked at first using the Nav system in the 2012 because it made me less aware of where I actually was, geographically. I would just "follow the yellow road" to my destination (and got hooked on doing so). But the positive consequence in doing that was that a whole new world of relative altitude opened up. Fortunately, I travel in an area with terrain that makes for interesting observation and quick learning.

And now in my 2015 S, I've "happily" lost the navigation system, so I once again have to know where I am (as it were); but this "old-school"/nav-less driving experience is now enriched by the topographical awareness which has been, and continues to be, ingrained in me.