Temperature bars & real temps

[asimba2]

Can anyone tell me what the approximate temperature ranges are for each temperature bar on the dash display? It was 92 degrees yesterday and I saw 6 temp bars during L2 charging and even several hours after charging. This morning it was only 64 degrees and even after a long freeway commute the dash display still showed 6 temperature bars the entire drive.

 

[Stanton]

If you (Google) search the forums there were some good threads early on with screen shots of the manual and temp bar ranges which were REMOVED from later editions. Here's a couple of tips though:
1) The battery pack has a lot of mass, so it changes temp slowly (in both directions)
2) The temp bar ranges CHANGE as you lose battery capacity (e.g. 7TB may trigger @100 degrees on a "new" pack but @105 degrees after you lose a CB or two)
3) If you're really concerned about temps (like I am in TX), invest in something like a LeafDD or LeafSpy which will give you actual pack temps (instead of just a "dumb" bar).

 

[Weatherman]

The sixth bar has a very wide range. It's anything from the lower 70s to around 100F.

Also, as the battery degrades, the temperature range shifts upward. With a 20%-degraded battery, the sixth bar won't show up until the battery temp is in the upper 70s to near 80F.

 

[asimba2]

The sixth bar has a very wide range. It's anything from the lower 70s to around 100F.

Thanks for the replies. I will get a LeafDD eventually.

 

[TomT]

He only has a small number left and when they are sold there will be no more. So, if you want one, get it now.

The sixth bar has a very wide range. It's anything from the lower 70s to around 100F.

Thanks for the replies. I will get a LeafDD eventually.

 

[TonyWilliams]

LEAF Batt Temp
Segments Degrees C (F). Temp difference
12----------60---------(140).........4.5F
11----------57.5-------(135.5)......4.5F
10----------55---------(131).........4.5F
9-----------52.5-------(126.5)......4.5F
8-----------50---------(122)........23.8F
7-----------36.8-------(98.2)......23.9F
6-----------23.5-------(74.3)......23.9F
5-----------10.3-------(50.5)......23.9F
4----------/ -3---------(26.6).......5.4F
3----------/ -6---------(21.2).......5.4F
2----------/ -9---------(15.8).......5.4F
1----------/-12--------(10.4).......5.4F
0----------/ -15---------(5).........5.4F

 

[asimba2]

Thank you Tony. With temperatures rising I will probably be seeing 7 bars on a somewhat regular basis. Thankfully I park in a parking garage at work where the car does not get direct sun, and the car takes on its 80% charge in the morning, so things could be worse.

 

[cwerdna]

I'm not sure Tony's table is right. It doesn't agree with http://www.electricvehiclewiki.com/Battery#Battery_Temperature_Gauge" onclick="window.open(this.href);return false;.

 

[JeremyW]

Thank you Tony. With temperatures rising I will probably be seeing 7 bars on a somewhat regular basis. Thankfully I park in a parking garage at work where the car does not get direct sun, and the car takes on its 80% charge in the morning, so things could be worse.

When I lived in Folsom I typically saw 6 TB nearly all the time in the Summer, with only a few 7TB, usually by charging at work in the afternoon in the direct sun. I parked in a garage and had shaded parking (under solar panels!).

This was before we had direct pack temperatures, but I'd guess the pack stayed in the upper 80's to mid 90's all summer.

If you can leave the car outside at night you could see a bit of heat rejection compared to the garage. Summer nights can be 30 degrees cooler than the daytime highs.

 

[RegGuheert]

I'm not sure Tony's table is right. It doesn't agree with http://www.electricvehiclewiki.com/Battery#Battery_Temperature_Gauge" onclick="window.open(this.href);return false;.

Tony's table is what was original published in the 2011 LEAF Service Manual and it matches what most of us see. The table in the Wiki is what was later published in the 2011 LEAF Service Manual and is a major source of confusion since there is so much overlap in the ranges with a vague note related to degradation. The implication is that the bars will move around as the battery degrades, but I'm not sure we have been able to confirm that.

In any case, for a newer LEAF, the numbers Tony provided seem to be pretty accurate.

 

[asimba2]

If you can leave the car outside at night you could see a bit of heat rejection compared to the garage. Summer nights can be 30 degrees cooler than the daytime highs.

That's exactly what I do--my garage is south-facing and gets really hot inside by the end of the day. Since the Leaf is our leased car, it gets parked outside while the cars we own get the garage. The hot engine blocks from the cars heat it up even more, so I think parking the Leaf outside actually works better. During the work-week, the Leaf gets charged in the morning and sits inside a parking garage that usually has a breeze blowing through it.

Regardless of which temperature chart you use, both show a lot of overlap in temperatures, so my concern is nil. Thanks for the info.

 

[RegGuheert]

Regardless of which temperature chart you use, both show a lot of overlap in temperatures, so my concern is nil. Thanks for the info.

Tony's table does not have any overlap between bars. It tells at what temperature you can expect a given bar to light.

 

[kieranmullen]

I am in Oregon and the last month has been pretty mild. I have made just some short slow trips and I see 6 TB Should I be worried that doesn't seem normal since you guys treat 6 as not so good.
Is there a guide out there for temperatures? Good bad etc..

 

[cwerdna]

I am in Oregon and the last month has been pretty mild. I have made just some short slow trips and I see 6 TB Should I be worried that doesn't seem normal since you guys treat 6 as not so good.
Is there a guide out there for temperatures? Good bad etc..

Beats me. I don't monitor it carefully, but I sometimes see 6 TB even when it's not hot out (I'm in the South Bay, so it's not nearly as cool on most summer days as SF). I don't recall ever going below 4 TB for me, but my memory might be foggy.

Look how high Tony got it up to at ~2:57 of https://www.youtube.com/watch?v=mqd9qbvBoME" onclick="window.open(this.href);return false;. :shock: That was from multiple QCs a day. I also recall when he was making that drive, it was quite hot throughout Nor Cal as he was passing thru the area.

And for the opposite: https://www.youtube.com/watch?v=Vz2WzLQ2tqg" onclick="window.open(this.href);return false;.

 

[asimba2]

It has been 103 degrees in Sacramento lately and for the last few days I have seen 7 temperature bars. The chart Tony posted says 7 bars show at 98.2 degrees F where the wiki says 117F. I started to wonder about how the TMS works on other EVs and based on the diagnostic screenshots I have seen from a Tesla Model S, battery active cooling does not even begin until 55deg C (131deg F).

Meanwhile, a Focus electric can't active cool when unplugged (say, while you are at work, during the hottest part of the day) and a Volt will only actively cool while unplugged if SOC is greater than 75% (hard to do on a 16kw battery). Is this consistent with what others have seen?

 

[TomT]

The leaf (and I assume other EV's battery packs) have a great deal of thermal mass and temperature adapt from external ambient very slowly. Thus, actively cooling the battery when plugged in can have significant advantages and effect even well after you have unplugged and through the day...

Meanwhile, a Focus electric can't active cool when unplugged (say, while you are at work, during the hottest part of the day) and a Volt will only actively cool while unplugged if SOC is greater than 75% (hard to do on a 16kw battery).

 

[asimba2]

Let's assume my Leaf had a Model S' thermal management system. Active cooling wouldn't begin until I hit the 10th bar.

LEAF Batt Temp
Segments Degrees C (F). Temp difference
12----------60---------(140).........4.5F
11----------57.5-------(135.5)......4.5F
10----------55---------(131).........4.5F
9-----------52.5-------(126.5)......4.5F
8-----------50---------(122)........23.8F
7-----------36.8-------(98.2)......23.9F
6-----------23.5-------(74.3)......23.9F
5-----------10.3-------(50.5)......23.9F
4----------/ -3---------(26.6).......5.4F
3----------/ -6---------(21.2).......5.4F
2----------/ -9---------(15.8).......5.4F
1----------/-12--------(10.4).......5.4F
0----------/ -15---------(5).........5.4F

 

[LEAFfan]

My 2013 goes from TB 6 to 7 when the bat temp reaches around 98F and today it went from 7 to 8 TBs around 109 bat temp. Ambient was 110F.

 

[davidcary]

I too was impressed at how little Tesla's TMS does in "normal" activity and modest temps (ie not Arizona).

It really makes the whole argument for TMS fall on its face. The issue isn't the lack of TMS, it is the battery design for most of us. Sure if you QC in Arizona or track a Tesla, you need to cool. But living in NC without a QC port, I certainly never see 8 bars and I see 7 bars fairly rarely (if memory serves). If I had a Tesla, the active cooling would have never turned on. Boy would I hate to pay $1000? for something that was never used. On the other hand, cheap insurance I guess.

I for one would be happy with a lizard battery. I'd surely be happy with a 40kwh battery too. Active cooling could be a "hot weather package" for those in Arizona etc.

 

[asimba2]

I thought active cooling was a fantastic idea until I started looking into it more. Tesla roadsters started active cooling at 40deg C (104F) and many owners were finding the car's TMS using 12kw of energy on a hot day to keep the battery cool. In most cases TMS does nothing for you unless you car sits in a parking lot all day plugged in. But now that you're plugged in, you will have a high SOC all day and you also can't take advantage of off-peak utility rates. The answer there is a user-adjustable charge limit, something I *do* want on my next EV.