Capacity Loss on 2011-2012 LEAFs

[zarwin]

With current temps in 110F, I think I have reasonable solution to keep battery in reasonable temp using AC window unit that blow cold air under the car.

Did you rig up a duct to channel the cold air under the car?.. 5000 BTU window AC consume about 500Wh or so when the compressor is running.

Power consumption was somewhere in .8kWH range, I made the duct using pieces of foam and blocked air under the car, car is parked very close to garage door so AC is placed under partially opened garage door insulated with foam whenever possible. Temp at 7 am in garage was 80 but under car and battery 70. Will do it again tonight temp at midnight about 95F.

zarwin are you in PHX area?

No, actually in North Carolina. I know, I know, why would I bother with this I'm not in a super hot climate. Well,

- I already had the AC in the garage before getting the Leaf
- It sits in a parking lot with no shade all day and will show 7TB bars if the ambient temp is in the high 90s with full sun, which is quite often this summer
- I purchased instead of leased and want to baby the battery as much as possible so I can keep the car for a very long time

Wasting time screwing with a duct is beyond overkill for this environment, and its more of just the tinkerer in me that wants to do these things I suppose.

 

[EdmondLeaf]

On weekends I charged to 100% due to more driving. My battery check was preformed on 5/9/2012 and I got 5 stars for every item , except for "frequent charging when battery state is already high", I got 4 stars. Prehaps this with the heat did the pack in.

"frequent charging when battery state is already high" in your case is probably due to remote CC after charging to 80%. I agree summer heat is a reason and we are in it again, it will be nice if Leaf have a way to cool battery down.

 

[ecoobsessive]

I know we're getting a little off topic (mods you can move this to the "cooling thread" if you want) since everyone is talking about cooling the battery/garage. What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit. I never had used the remote CC, but one day when the car was hot from being in the sun I left the car running in the garage with the AC on high for about 10 minutes. I could feel lots of nice cold air coming out the cracked windows. The garage temp went from 88 to 87 during those 10 minutes. I know the idea is to cool the battery, not the garage, but if the inside of the car is plenty cool, and if you turned on remote CC for 10 minutes every 6 hours or so - if that would help the battery, it would certainly be my choice -rather than getting an AC for the garage.

 

[OrientExpress]

Added to Wiki. We just need your city and VIN number (last 5 digits) to complete your entry.

I got a chance to review this Wiki list today, and noticed that the most important piece of data for each entry is missing. Having the original delivery date is a very important piece of data for trend analysis. That data is not included in the lists.

I would highly recommend that this field be added, and then each entry updated.

 

[DaveinOlyWA]

*charging to 100%" on weekends due to more driving need is the problem caused by lack of public support.

i drive more on weekends but rarely charge to more than 40-50%. if I do decide i need more, i jump over to the DCFC for a 10-15 minute pitstop and as long as it is free, i also notice my average EV charging bill has dropped from $30 to $20 while at the same time i am in the top 100 for distance driven (first time not counting back when there was only about 110 LEAFs registered at Carwings...) this month!

 

[Stoaty]

I got a chance to review this Wiki list today, and noticed that the most important piece of data for each entry is missing. Having the original delivery date is a very important piece of data for trend analysis. That data is not included in the lists.

I would highly recommend that this field be added, and then each entry updated.

Agreed, but it is hard enough just to get people to file a case and give the case number, or provide relevant information. I sent a PM to people with missing info, got about 5 responses out of 15-20 sent. It is almost impossible to contact people who are not on the forum, and many on the forum, even those who are still posting, simply don't respond whether to PM or to a list I posted in one of the threads. If anyone has a better idea about how to collect more data, I am all ears.

 

[JRP3]

I know we're getting a little off topic (mods you can move this to the "cooling thread" if you want) since everyone is talking about cooling the battery/garage. What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit. I never had used the remote CC, but one day when the car was hot from being in the sun I left the car running in the garage with the AC on high for about 10 minutes. I could feel lots of nice cold air coming out the cracked windows. The garage temp went from 88 to 87 during those 10 minutes. I know the idea is to cool the battery, not the garage, but if the inside of the car is plenty cool, and if you turned on remote CC for 10 minutes every 6 hours or so - if that would help the battery, it would certainly be my choice -rather than getting an AC for the garage.

Not sure that would work. The A/C works by shedding heat into the surrounding air to provide cool air into the cabin. Running the A/C in a closed garage cannot lower the overall temperature, though the stream of cold air coming out of the cabin might show some localized cooling. Actually I guess if you could direct the cool air from the cabin under the car to the battery it might cool the battery while heating up the air above. So maybe it can work, sort of.

 

[RegGuheert]

What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit.

I think that will heat your garage.

But perhaps if you can get flow down through the battery disconnect hatch you could do something. Perhaps set the A/C to bring in outside air instead of recirculate you could force some of the cold air down through the hatch. (I don't know where the air normally exhausts. Is it back near the taillights somewhere?). This approach will also heat the garage overall, but perhaps it will make the battery cooler.

BTW, be careful if you do either of these things since you will raise your battery SOC if plugged in and you will lower it if not plugged in. Too high or too low SOC is not good.

 

[OrientExpress]

Agreed, but it is hard enough just to get people to file a case and give the case number, or provide relevant information. I sent a PM to people with missing info, got about 5 responses out of 15-20 sent. It is almost impossible to contact people who are not on the forum, and many on the forum, even those who are still posting, simply don't respond whether to PM or to a list I posted in one of the threads. If anyone has a better idea about how to collect more data, I am all ears.

We can infer the delivery date from the data you have, but it should just be there. Do you think we could take a stab at figuring it out from what is already posted there?

 

[padamson1]

What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit.

Not sure why the temp went down in the garage doing this as it violates thermodynamics. It is the same as trying to cool your house with your refrigerator. An electrical A/C unit takes heat out of one air space (cooling it) and moves it to another (heating that) typically using a fluid with specific heat capacity. That's why heavy usage of A/C contributes to heat islands.

If you stuck the front end of the LEAF (where the evaporative AC unit is) outside of the garage with the passenger compartment inside, then you could change the temp in the garage.

 

[DaveinOlyWA]

What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit.

Not sure why the temp went down in the garage doing this as it violates thermodynamics. It is the same as trying to cool your house with your refrigerator. An electrical A/C unit takes heat out of one air space (cooling it) and moves it to another (heating that) typically using a fluid with specific heat capacity. That's why heavy usage of A/C contributes to heat islands.

If you stuck the front end of the LEAF (where the evaporative AC unit is) outside of the garage with the passenger compartment inside, then you could change the temp in the garage.

sure it does, but the garage is not airtight and probably poorly insulated as well and on and on and on. what he saw had nothing to do with the AC being on. the temperature would have changed anyway

 

[edatoakrun]

Agreed, but it is hard enough just to get people to file a case and give the case number, or provide relevant information. I sent a PM to people with missing info, got about 5 responses out of 15-20 sent. It is almost impossible to contact people who are not on the forum, and many on the forum, even those who are still posting, simply don't respond whether to PM or to a list I posted in one of the threads. If anyone has a better idea about how to collect more data, I am all ears.

We can infer the delivery date from the data you have, but it should just be there. Do you think we could take a stab at figuring it out from what is already posted there?

IMO, the ideal would be to list the date (month) of manufacture, date of delivery, and date of bar loss, marked with an * if when the loss was "noticed".

Many LEAFs started out as orphans, delayed deliveries, etc., and delivery date may not tell the whole story.

BTW, does anyone know if individual modules or battery packs are identified by date of manufacture?

Calendar aging for some batteries, could have begun some time before vehicle manufacture, I'd think. Especially early in production, and after the tsunami, when "just in time" battery pack production/manufacturing schedules could have been compromised.

 

[Stoaty]

IMO, the ideal would be to list the date (month) of manufacture, date of delivery, and date of bar loss, marked with an * if when the loss was "noticed".

I would be happy to modify the table to include columns for this information, but I doubt we will be able to get enough of this data filled in to draw any meaningful conclusions. Perhaps we should collect the data first, then modify the table if we have sufficient information to fill it in.

 

[Stoaty]

Followup to the questions about my post.

I am in Wichita Falls, Texas. Last summer it was over 100f all summer. My car sat in a parking lot for over 8 hours everyday at work. Then it sat in my garage. I changed to 80% on work days, every day. My commute was 30 miles. On weekends I charged to 100% due to more driving. My battery check was preformed on 5/9/2012 and I got 5 stars for every item , except for "frequent charging when battery state is already high", I got 4 stars. Prehaps this with the heat did the pack in.

The last 5 numbers of my VIN are 01112.

Added to Wiki, thanks.

 

[edatoakrun]

What thoughts do ya'll have about leaving the car in a hot (90F) garage with with AC running with windows down a bit.

I think that will heat your garage....

Yes, I've been wondering how practical ATM such as the Volt has, which many seem to think the LEAF might benefit from, would actually be, particularly in a well-insulated garage, during long-term storage in a Phoenix-like climate.

The more the ATM cycles the car's AC, the hotter the garage gets, the lower the efficiency of the heat exchanger, the more time the AC system needs to run, drawing even more kWh from the grid, the hotter the garage gets...

 

[edatoakrun]

IMO, the ideal would be to list the date (month) of manufacture, date of delivery, and date of bar loss, marked with an * if when the loss was "noticed".

I would be happy to modify the table to include columns for this information, but I doubt we will be able to get enough of this data filled in to draw any meaningful conclusions. Perhaps we should collect the data first, then modify the table if we have sufficient information to fill it in.

I understand. Is there a "checklist" of information posted somewhere for bar loss reports you could add to?

Maybe post it at the top of the capacity loss page on the Wiki, so both new reports, and those who have already reported, could see the request for this, or any other missing data?

 

[RegGuheert]

Yes, I've been wondering how practical ATM such as the Volt has, which many seem to think the LEAF might benefit from, would actually be, particularly in a well-insulated garage, during long-term storage in a Phoenix-like climate.

I've been thinking for some time that in a garage containing both a Volt and a LEAF that the Volt removes some heat from its battery and puts it in the garage where it will tend to heat up the LEAF battery. :evil:

OTOH, it is probably NOTHING compared with the amount of heat an ICE brings into a garage and dumps.

 

[Stoaty]

I've been thinking for some time that in a garage containing both a Volt and a LEAF that the Volt removes some heat from its battery and puts it in the garage where it will tend to heat up the LEAF battery. :evil:

OTOH, it is probably NOTHING compared with the amount of heat an ICE brings into a garage and dumps.

And none of these can hold a candle to the heat from the big yellow orb in the sky over Phoenix.

 

[edatoakrun]

Yes, I've been wondering how practical ATM such as the Volt has, which many seem to think the LEAF might benefit from, would actually be, particularly in a well-insulated garage, during long-term storage in a Phoenix-like climate.

I've been thinking for some time that in a garage containing both a Volt and a LEAF that the Volt removes some heat from its battery and puts it in the garage where it will tend to heat up the LEAF battery. :evil:

OTOH, it is probably NOTHING compared with the amount of heat an ICE brings into a garage and dumps.

Actually, somewhere on this site, (if I find it, I'll edit with link to the on-topic thread) is a recent report of ATM Wh use from a Phoenix Volt owner that, IIRC, may contradict that belief. Found it:

...My measurements are from a TED (theenergydetective) and my conditions are in Phoenix in my garage which regularly reaches well over 100F, sometimes over 110F. Somewhat severe.

The Volt TMS draws 800-900 watts for about 10-15 minutes every few hours to lower the battery temps. Also after charging the TMS continues to operate for some time to bring the battery back to a reasonable temp, length of time is dependent, I think, on how long it charged and the ambient temp. You can hear it running during charge times as well...

http://www.mynissanleaf.com/viewtopic.php?f=9&t=9525&start=10" onclick="window.open(this.href);return false;

The heat brought in by an ICE is a one-time event. While every Wh used pulled from the grid to run the ATM (after an extremely complicated thermal cycle) eventually winds up as hot air, in the garage.

 

[TonyWilliams]

I've been thinking for some time that in a garage containing both a Volt and a LEAF that the Volt removes some heat from its battery and puts it in the garage where it will tend to heat up the LEAF battery. :evil:

OTOH, it is probably NOTHING compared with the amount of heat an ICE brings into a garage and dumps.

And none of these can hold a candle to the heat from the big yellow orb in the sky over Phoenix.

Curses!!! If we can just snuff that out, we're good to go.