Phoenix and Hot Climate Leafs - Try L1 Charging

[09Bamb00]

however, I know that I can't make the round trip without stopping to charge somewhere. The best time was driving 5 miles to Kohl's charging for one hour to get one bar which gave me enough range to make it to the library where I charged for 2 hours for 1.5 bars (both 240v) so I could make the last 20 miles home.

 

[Herm]

Most of the commute is on a highway at 70 mph (minimum speed limit), with the radio.

You sure its not 70 mph maximum?.. try driving at 60 one day (on the right lane) and see if there is a difference on your range..

 

[PugLady]

My 240V EVSE charger should be here any day now so for now I charge with 110 over night and 240 during the day at work.

Because I live in sunny Florida, I can't leave the car charging outside at night as I never know when a thunderstorm might decide to visit. (I'm paranoid about waking up to no electricity and a car fire.) And I'm not too happy about leaving a door ajar to accommodate the cord as the sole single use outlet is directly under the electrical panel. On the 110 charger I have to start within the first hour that I get home otherwise it doesn't make enough electricity to get me to work the following day. My commute is 47+/- one way.

I find that the stated 'range' has nothing to do with reality. In the morning the Leaf states that I have an 87 mile range. By the time I've backed out of the garage and driven the four blocks to the first light doing 35 mph, the range has dropped to 69 miles. When I arrive at work, it reads 29 mile range. Meanwhile the actual miles is 47+/-. Most of the commute is on a highway at 70 mph (minimum speed limit), with the radio. Sometimes with lights on and sometimes with the air conditioning running. On those days I have a 19 mile range by the time I get to work.

On the drive home, I almost always run the air conditioner, the lights and the windshield wipers because the afternoon monsoon rainy season is upon us. So I start out at around 101-87 mile range (for some reason I get these numbers when I use 240v charger). Once again, I'm down to 35-19 mile range when I get home. Some days when I have used the constant wiper setting, I have had to stop to a car charging station about 20 miles from home to get enough juice to make it home.

Anyway, it will be nice to be able to go out further than walking distance when I get home, which is why I'm looking forward to the 240 charger arrival.

Pardon me for the observation, but from the GOM figures, it almost appears like you charge to 80% overnight and 100% during the day....

 

[09Bamb00]

Pardon me for the observation, but from the GOM figures, it almost appears like you charge to 80% overnight and 100% during the day....

Yeah, doesn't it? However it says 12 bars...

I got brave last night and left the Leaf outside. It was 76F. Didn't change the heat bars, they remained at 6. It has been like that since one week after I purchased the car.

Today there was an accident on I4, so I was traveling at 10 mph average for the last 15 miles and I still used 7 bars or 29 range when I arrived at work. Before that I was traveling cruise control 70 mph with lights.

 

[DaveEV]

I got brave last night and left the Leaf outside. It was 76F. Didn't change the heat bars, they remained at 6. It has been like that since one week after I purchased the car.

You're not going to see less than 6 temp bars unless the car sits at temps under 75F. Even here in coastal San Diego my car doesn't get to 5 bars most of the time unless I leave a side garage door open past midnight which is enough to cool the garage to the low 70s (even with lows in the low 60s - so the garage normally stays 10F+ warmer than ambient). And then it quickly jumps back up to 6 bars on the drive in to work, so it's definitely not much cooler than 75F.

http://www.mynissanleaf.com/wiki/index.php?title=Battery,_Charging_System#Battery_Temperature_Gauge" onclick="window.open(this.href);return false;

That said, if it gets much cooler outside than inside at night as I suspect is the case the majority of the time, that's going to help increase the life of your battery.

 

[jstack6]

L1 vs 2 or even Fast Charging won't help. I also live in Chandler and it's the HEAT that is dropping battery capacity very fast. A few have already lost 3 bars and over 30% range...

TV5 news just did a story on it 7-17-2012 at 10 pm. It's a big problem and all hot areas will have the same loss.

Note that the TESLA and eveen CODA have thermal management, while the LEAF has none,not even a fan like a prius has.

CODA Active Thermal Management
Batteries, like people, prefer moderate temperatures. Our air-controlled Active Thermal Management System keeps the pack from getting too hot or too cold in various weather conditions. This not only provides you with consistent driving range, it maximizes the overall battery life.

 

[mark13]

Ill try a 100% charge with the L1 when it cools down,sometime in Oct..

 

[ydnas7]

Since tracking my Gid count daily in June and July here in Phoenix (South Chandler area), I've been losing approximately 1 GID a day, L2 charging to 80%, particularly on the hot days. My garage temperature has been sitting around 92 degrees at night, very close to the outside temperature, as I'm trying to use a fan to keep the garage.

This past Monday evening, I parked outside and L1 charged at night to 80%. And since then, I've not lost 1 GID yet.

Monday and Tuesday were particularly hot days, also. Driving home Monday, with the car parked in an outdoor parking lot, my car registered 120 degrees. Then it cooled down to 116 on the drive home. Based on my previous readings, I fully expected to lose 1 GID by the next morning. Tuesday was a little cooler, but still in the 115 range. Nighttime temperature only got as low as 93 degrees.

My GID count this morning, after 80% L1 charging both evenings, is still at 185.

3 points to make

parking outside allows the car to cool down better than a garage attached to a single level house
(ground is cooler than concrete + outside air is cooler than garage air)

L1 charging being slower to some extent replicates end timer charging on L2
(battery does not sit with a high level SOC all night long)

although this is a very small sample, it is suggesting that by combining 2 simple changes to charging protocol, that hot desert LEAFs could at least triple their battery pack life...

 

[Stanton]

A co-worker here has a Leaf that has not lost a capacity bar, parks outside during the day, and uses L1 charging at night.

Interesting! Can you please tell us when your co-worker purchased the car?

We still need more details about this car. While the claim is interesting, without more data it doesn't obfuscate the basic premise that long-term exposure to HEAT is the main problem. Having said that, I use an end-timer (only) to charge early in the AM and DON'T opportunity charge during the day when I have >6TB (which isn't that often).

 

[DaveinOlyWA]

one point to make.

heat acts as a catalyst in any chemical reaction. iow, it extends the reaction % and makes it work faster.

the LEAF BMS is designed to not overcharge the system but the system is not working in Phoenix which is resulting in premature capacity loss. so why is this happening?

they are charging their LEAF during coolest part of day. charge is completing during coolest part of the day then they lose capacity.

reason; heat. if i lived in Phoenix, i would try to charge after the sun has come up to allow the BMS to limit the charge to prevent the damage at a temperature the car is likely to see thru out the day.

where i see the loss happening is the very short window when car is charged and sitting but warming up before the first drive of the day. this allows pack to heat up creating a charge beyond the BMS spec, all of which results in permanent pack loss. now this is amounting to a very small fraction of one percent. but if done daily all summer, we are talking about 120-140 days of potential loss annually

 

[phxsmiley]

A co-worker here has a Leaf that has not lost a capacity bar, parks outside during the day, and uses L1 charging at night.

Interesting! Can you please tell us when your co-worker purchased the car?

We still need more details about this car. While the claim is interesting, without more data it doesn't obfuscate the basic premise that long-term exposure to HEAT is the main problem. Having said that, I use an end-timer (only) to charge early in the AM and DON'T opportunity charge during the day when I have >6TB (which isn't that often).

I'll provide more information tomorrow. I'm meeting with them tomorrow morning to take a GID reading. She says they bought their car in September, a month after my car.

 

[surfingslovak]

where i see the loss happening is the very short window when car is charged and sitting but warming up before the first drive of the day. this allows pack to heat up creating a charge beyond the BMS spec, all of which results in permanent pack loss. now this is amounting to a very small fraction of one percent. but if done daily all summer, we are talking about 120-140 days of potential loss annually

Dave, good theory, but I don't see it the same way. When you look at TickTock's Gid plot there seems to be a good degree of seasonality. I would not expect to regain full battery capacity until fall and winter. Separately from that Tony recently confirmed that the battery limits maximum charge level as temperature rises after a QC. I think that parking the car outside or in a carport overnight is a good idea. Cooling the garage down a bit should help too. Charging to less than full with an end timer or on L1 and seeking a cool parking spot seem like sensible defensive steps.

 

[DaveinOlyWA]

its a bit of a shot in the dark and seasonal adjustments of capacity is definitely part of it but that is temporary loss which will come back. in Phoenix, how much is temporary? hard to say.

but one thing i can say; charging during coolest part of the day appears to be a major fail. for me; i am not a scientific guy. i am an "observation" guy which is obviously flawed since "point of view" inherently is flawed. look the the "world is flat" debate or the "we are the center of the universe" controversy...

so if "A" does not work. lets try "B" because it is not completely out of the question and from what i can see, the actual temps the batteries are seeing (guessing around 140º F) should not be enough to boil anything or whatever so it has to be related to temperature limited maximum SOC ...

 

[thankyouOB]

The discussion here just highlights why we need NISSAN to get out in public on this.
we have many theories and a variety of coping strategies for prolonging battery life, but no one really knows which path to follow.

among the options for me are end charging, charging L1 or L2, charging to full at home or charging partially at home and at work to reduce extremes in pack capacities, charging when cooler or not, charging outdoors or underground lot.
I can do any and all of these, but all I have is informed speculation about the best strategy to employ.
other than charging to 80%, NISSAN has pretty much left me in the dark.

I am sure they have data that would support or debunk some of these tactics for giving the pack longevity and prolonging capacity.

 

[DaveinOlyWA]

The discussion here just highlights why we need NISSAN to get out in public on this.
we have many theories and a variety of coping strategies for prolonging battery life, but no one really knows which path to follow.

among the options for me are end charging, charging L1 or L2, charging to full at home or charging partially at home and at work to reduce extremes in pack capacities, charging when cooler or not, charging outdoors or underground lot.
I can do any and all of these, but all I have is informed speculation about the best strategy to employ.
other than charging to 80%, NISSAN has pretty much left me in the dark.

I am sure they have data that would support or debunk some of these tactics for giving the pack longevity and prolonging capacity.

do you have any loss?

if you can charge at work, i would NEVER go above 80%. never go below 25%. u be golden.

also, there is a lot of concern over what temps we need to be wary of. i doubt you have an issue. you will see some loss because you are supposed to no matter what but it wont be aggravated by heat.

problem with Phoenix is that they go MONTHS and never see anything below 90...that is RIDICULOUS...

 

[DaveEV]

heat acts as a catalyst in any chemical reaction. iow, it extends the reaction % and makes it work faster.

True.

reason; heat. if i lived in Phoenix, i would try to charge after the sun has come up to allow the BMS to limit the charge to prevent the damage at a temperature the car is likely to see thru out the day.

where i see the loss happening is the very short window when car is charged and sitting but warming up before the first drive of the day.

That doesn't make any sense. Warming up a battery pack doesn't "create" additional charge. Warming up a pack only speeds up chemical reaction in the battery as you say, so it only appears to create additional charge since the internal resistance of the pack goes down as the pack warms up.

It's not like the voltage of the pack changes with temperature to any significant degree, which would indicate a change in SOC.

 

[thankyouOB]

do you have any loss?

if you can charge at work, i would NEVER go above 80%. never go below 25%. u be golden.

also, there is a lot of concern over what temps we need to be wary of. i doubt you have an issue. you will see some loss because you are supposed to no matter what but it wont be aggravated by heat.

problem with Phoenix is that they go MONTHS and never see anything below 90...that is RIDICULOUS...

i dont have access to a gid meter.
i dont see any loss, but then, unlike my first 8 months of ownership, I now charge at work daily. that is to say, I do not do the roundtrip to home, so I have no comparative measures.

 

[DaveinOlyWA]

do you have any loss?

if you can charge at work, i would NEVER go above 80%. never go below 25%. u be golden.

also, there is a lot of concern over what temps we need to be wary of. i doubt you have an issue. you will see some loss because you are supposed to no matter what but it wont be aggravated by heat.

problem with Phoenix is that they go MONTHS and never see anything below 90...that is RIDICULOUS...

i dont have access to a gid meter.
i dont see any loss, but then, unlike my first 8 months of ownership, I now charge at work daily. that is to say, I do not do the roundtrip to home, so I have no comparative measures.

i think you are better off to get a boost charge at work. the Prius runs its SOC from 40 to 80%. i know its different chemistry but its hard to argue their track record

 

[ydnas7]

The discussion here just highlights why we need NISSAN to get out in public on this.
we have many theories and a variety of coping strategies for prolonging battery life, but no one really knows which path to follow.

among the options for me are end charging, charging L1 or L2, charging to full at home or charging partially at home and at work to reduce extremes in pack capacities, charging when cooler or not, charging outdoors or underground lot.
I can do any and all of these, but all I have is informed speculation about the best strategy to employ.
other than charging to 80%, NISSAN has pretty much left me in the dark.

I am sure they have data that would support or debunk some of these tactics for giving the pack longevity and prolonging capacity.

If you are in Arizona, DO NOT charge up at work to 80% SOC if you can avoid it.

look at the fastest one to lose 1 bar capacity - johndoe74 - 9 months

My wife's Leaf of 9 months, 13500 miles also lost one battery bar, about two weeks ago. We live in Chandler, AZ.

The car is parked 90% of the time in a garage. In the first 2 months after getting the car, we charged it 100% every night, but since then we only charge to 80%.

The daily commute is about 30 miles (sometimes 45 miles with errands) each way, charge again to 80% at work, then another 30 miles going home.

They did not not realize that because they were in Arizona and not California that they were killing their battery by maintaining an elevated SOC for as long as they could.

Charge as late and as cool as possible, Are there any who park outside at night in Arizona with a lost capacity bar?

 

[DaveinOlyWA]

reason; heat. if i lived in Phoenix, i would try to charge after the sun has come up to allow the BMS to limit the charge to prevent the damage at a temperature the car is likely to see thru out the day.

where i see the loss happening is the very short window when car is charged and sitting but warming up before the first drive of the day.

That doesn't make any sense. Warming up a battery pack doesn't "create" additional charge. Warming up a pack only speeds up chemical reaction in the battery as you say, so it only appears to create additional charge since the internal resistance of the pack goes down as the pack warms up.

It's not like the voltage of the pack changes with temperature to any significant degree, which would indicate a change in SOC.

well as i recall (which i do very poorly) power can be expressed in several ways

P=IE (watts= amps *volts) or P=I2R (watts = amps (squared) * resistance)

or P=V2/R so if "R" changes either the power stored will change (you claim it does not) or the voltage must change, so we have high voltage instead of overcharging? or high voltage is the result of overcharging