Li-On Temperature bar tutorial, please

[DaveinOlyWA]

probably too early to say but after my hot charging experiment, i seem to notice that 6 TBs is easier to obtain. i had only 5 TBs last night when i parked it. garage was at 25 C. plugged in and charged at 11:30 finished at 4:18 am and had 6 TBs morning temp 19.9 C

in normal circumstances i would have 5 TBs so it seems my LEAF has become a bit "heat sensitive" now, i did not leave garage door open much after sundown like i normally do. (SO works late and typically not home until near 9 PM) and that would have caused the warmer than normal temps of 25C that we saw now that 25C was a declining temp and ambient was as high as 28C earlier in the day but remember, it was only 5TB when i parked it so the charging had to be the culprit that boosted the 6 TB,

once again, it seems more data just brings up more questions

 

[dgpcolorado]

Probably for the same reason that they won't give us actual SOC...

What I don't get is why Nissan changes the temperature scale as the battery degrades? I can't fathom why they deemed that change in temperature bars useful. It would have been nice if they had just given us the actual battery temperature (an average of the sensors would be fine) rather than the obscure bars.

I can see why they didn't want to give actual SOC: the value would fluctuate because the voltages measured vary during use, as compared to a resting battery. And those fluctuations in readings could be confusing to drivers ("why is my SOC reading bouncing around?").

But temperature? Those numbers would figure to be quite stable given the thermal mass of the battery. I'd sure like to know if my 6 temp bar battery is at 74º or 90º.

 

[dgpcolorado]

I can certainly see your point, but common sense also says that your interpretation of the original table can't be possible. If 74°F is the minimum for 6 bars, then 5°F is the minimum for 0 bars, meaning that you would not be allowed to start the car if it had been sitting outside for some time at zero degrees. That hardly seems likely.

I think data (observations) should always trump some hypothetical situation. All observations agree that the transition point is about 74 degrees F. for a new(ish) battery.

Exactly. I watched just such a switch from five to six temp bars yesterday. Ambient temperature was mid 70s but the switch didn't happen until I pulled some decent kW from the battery, thus heating it slightly. I've seen this over and over for both five/six and four/five. After awhile one gets a feel for it and I've never seen anything that differed from the expected temperatures for a new battery in the original temperature table.

As for the 0 temp bars question, IIRC jkirkebo has reported on his experiences with 0 bars in Norway. The battery heater should prevent the battery from falling below the safety limit.

I realize that all this stuff is anecdotal, but without real data from the temp sensors there isn't much else we can do except go with our observations.

 

[SierraQ]

You California/Colorado people are funny.

"Aaaaaa! I got 6 bars! Why!?!"

In Texas/Arizona we are more like:

"Hey! I'm down to 6 bars! Excellent!"

 

[thankyouOB]

more anecdotal.

--this one is about charging as the apparent cause of battery temperature being above ambient temp.


I had 6 temp bars for the first time this AM. Typically, I have temp 5 bars.
I had charged for 90 minutes L2 from 530-7 am to get to 8 battery level bars for my trip to work.
outside temp was 68 degrees on the Leaf thermometer, when I got in the car and started up.
The temp bar read 6 bars.

I would suppose that charging caused the temp rise.

 

[garygid]

If we can discover how to read the four Pack temperatures, the cell-pair voltages,
and the tire pressures, we might be able to read them every 10 seconds (or so) and
include them in the Black-Box log data.

Who has an "in" with a Consult III+ testing machine?

 

[KJD]

If we can discover how to read the four Pack temperatures, the cell-pair voltages,
and the tire pressures, we might be able to read them every 10 seconds (or so) and
include them in the Black-Box log data.
Who has an "in" with a Consult III+ testing machine?

Gary, if you had a tester like this one, could you figure out how to read Battery Pack temps with your GID meter ?
http://www.ecutool.com/Nissan-Consult-III_3076.html" onclick="window.open(this.href);return false;

 

[TomT]

I believe you need the Plus version for the Leaf...

Gary, if you had a tester like this one, could you figure out how to read Battery Pack temps with your GID meter ?http://www.ecutool.com/Nissan-Consult-III_3076.html

 

[garygid]

Are these Chinese knock-offs of the Nissan tools?

Are any of the three "cards" needed for what we would need to do?

Immobilizer
Battery Registration
GTA (or some such)

Is the software complete and up to date?

Does the software need an activation key from Nissan?

Yes, I have only heard of "3 plus" in the context of the LEAF.

So, your question would be good for a Nissan tech to answer.

I would probably use the USB interface, rather than the bluetooth.

Requires an XP SP2 or SP3 operating system.

 

[TonyWilliams]

If we can discover how to read the four Pack temperatures, the cell-pair voltages,
and the tire pressures, we might be able to read them every 10 seconds (or so) and
include them in the Black-Box log data.

I'll offer (again) to drop my battery, remove the 4 thermistors, install a pigtail to mount the thermistors wherever you want, and reinstall the battery (I have all the needed tools to do this).

Then, put the thermistors under your tongue and measure 98.6F.

Then, stick them in the freezer. Look for the change in your datastreams. If you really want this, the ONLY real thing you'd have to do is search the data.

If that all works out, I'd be happy to do the same to your car.

 

[DaveinOlyWA]

more anecdotal.

--this one is about charging as the apparent cause of battery temperature being above ambient temp.


I had 6 temp bars for the first time this AM. Typically, I have temp 5 bars.
I had charged for 90 minutes L2 from 530-7 am to get to 8 battery level bars for my trip to work.
outside temp was 68 degrees on the Leaf thermometer, when I got in the car and started up.
The temp bar read 6 bars.

I would suppose that charging caused the temp rise.

i charged from 1 am to 6:15 am and checked it at 8 am and was at 5 TBs. garage temp was 18C