What is the best way to cool your battery.

[TonyWilliams]

An honest GOM is a bit like "Clean Coal".... I don't recommend trying to determine degradation based on the "more accurate" GOM.

 

[mwalsh]

Yep, I'm down about 8 Gids from the late fall...

Yes, this summer will certainly be interesting. Have Gid counts started to decline already? I believe we saw that in April and May last year.

I still don't understand (and am still waiting on Nissan to explain) how you can be two bars down @ 230 Gids while I still have all twelve at 228-234 Gids. And, yes, Gid counts are on the decline for me too - I've seen two 228 Gid mornings in the last week. Those are new lows.

 

[mwalsh]

I appear to be tracking between nominal and Boston. I think Nissan needs to give us an annual degradation check on our cars, so we can know for sure how we're doing and get the guess work and doubt out of the equation.

 

[RegGuheert]

I still don't understand (and am still waiting on Nissan to explain) how you can be two bars down @ 230 Gids while I still have all twelve at 228-234 Gids. And, yes, Gid counts are on the decline for me too - I've seen two 228 Gid mornings in the last week. Those are new lows.

That is odd! Do you have the same versions of BMS firmware installed?

 

[mwalsh]

I still don't understand (and am still waiting on Nissan to explain) how you can be two bars down @ 230 Gids while I still have all twelve at 228-234 Gids. And, yes, Gid counts are on the decline for me too - I've seen two 228 Gid mornings in the last week. Those are new lows.

That is odd! Do you have the same versions of BMS firmware installed?

Good point. So far as I know, I'm on the latest and greatest. - you'll remember they bricked my battery controller while trying to do the software updates a couple of months ago.

 

[TomT]

That is the question of the day/week/month/year! I'm not holding my breath waiting for an explanation from Nissan, however... :lol:

It does seem odd and counter-intuitive that you can still have all 12 bars at such a low Gid count however...

I still don't understand (and am still waiting on Nissan to explain) how you can be two bars down @ 230 Gids while I still have all twelve at 228-234 Gids. And, yes, Gid counts are on the decline for me too - I've seen two 228 Gid mornings in the last week. Those are new lows.

 

[mwalsh]

That is the question of the day/week/month/year! I'm not holding my breath waiting for an explanation from Nissan, however... :lol:

It does seem odd and counter-intuitive that you can still have all 12 bars at such a low Gid count however...

Are you current on software updates, so far as you know?

 

[TomT]

If 7,500 was used by the model (which is completely unrealistic IMHO), then I wonder if I should be looking at 4 years since I average about twice that mileage...
It is interesting because where I am now pretty much coincides with the graph at four years and nominal climate...

I only hope that the car will still have usable (for me) range when my lease is up at four years...

It's interesting that, based on their graph, I'm doing worse than Phoenix...

Yes, that's pretty puzzling. Wasn't the green curve in the chart above based on the mythical 7,500 annual miles, which Nissan engineers plugged into their model? I wonder what mileage projections were used for the blue and red curves.

 

[TomT]

Yep, I have the latest and greatest of everything to my knowledge.

Are you current on software updates, so far as you know?

 

[edatoakrun]

That is the question of the day/week/month/year! I'm not holding my breath waiting for an explanation from Nissan, however... :lol:

It does seem odd and counter-intuitive that you can still have all 12 bars at such a low Gid count however...

I still don't understand (and am still waiting on Nissan to explain) how you can be two bars down @ 230 Gids while I still have all twelve at 228-234 Gids. And, yes, Gid counts are on the decline for me too - I've seen two 228 Gid mornings in the last week. Those are new lows.

You suppose this just might be related to the fact that neither the capacity bar display nor the gid count has ever been show to accurately report actual battery capacity?

 

[RegGuheert]

You suppose this just might be related to the fact that neither the capacity bar display nor the gid count has ever been show to accurately report actual battery capacity?

I always thought that Gids were what Nissan used to determine battery degradation, so if they have the same number of Gids and the same firmware versions, why not the same number of bars showing?

 

[mwalsh]

You suppose this just might be related to the fact that neither the capacity bar display nor the gid count has ever been show to accurately report actual battery capacity?

Of course. But shouldn't it? Two years on from first deliveries. One year on from the first capacity issue trouble reports. Really?

 

[edatoakrun]

And I've lived in hotter climates, for all but 10 years of my Life.

More to the point, my LEAF has spent two full summers at considerably higher peak daytime temperatures, with no evidence of significant capacity loss.

Looks like overnight lows never exceeded 71 F in El Cajon over the Summer of 2012.

http://www.accuweather.com/en/us/el-cajon-ca/92020/july-weather/342295?monyr=7/1/2012" onclick="window.open(this.href);return false;

As I said previously, if you live anywhere in San Diego, and still suffer from "Battery degradation anxiety", park outside overnight, to let your battery pack cool.

I'm in a considerably cooler climate than SD, or even compared to the PNW, and I have noticeable capacity loss in fifteen months and 9000 miles...

If you have observations indicating this capacity loss, please report them, or provide the link to where you already have.

What I have seen you post is your comparison of your dash m/KWh to your "wall" meter:

="dgpcolorado"
Here is a seasonal chart of my mileage:

The pink line is my dash meter mileage.

http://www.mynissanleaf.com/viewtopic.php?f=50&t=11831&start=10" onclick="window.open(this.href);return false;

Though that image doesn't give very good resolution, and you use dash m/kWh rather than the more accurate CarWings kWh use reports, it appears you may be observing one or both of the same kWh use report errors I believe I have observed in my LEAF, both a seasonal error variation in your LEAFs kWh use reports (What appears to be a lesser distance between the two trend lines during warmer months) and much less distinctly in your case, an increasing error over time (as shown as the distance between the two lines on your graph, perhaps, tending to increase with time).

Would you please post these results in more useful detail?

I believe both of these effects may well have been more apparent in MY LEAF, due to the warmer climate it has experienced (as compared to yours) and similar reports from truly "hot" climate LEAFs might show one or both of these kWh use report errors to a greater degree.

 

[edatoakrun]

You suppose this just might be related to the fact that neither the capacity bar display nor the gid count has ever been show to accurately report actual battery capacity?

I always thought that Gids were what Nissan used to determine battery degradation...

Actually, IIRC, when Nissan took a number of Phoenix area LEAFs to examine them for capacity lose last Summer, they did not use either capacity bar displays or gid counts to determine available battery capacity, whether this is the precisely the same thing as "battery degradation" or not.

Nissan reportedly used measured battery discharge tests.

Since none of us have the equipment to replicate Nissan's methods, IMO, we can only depend on results from (less precise) range tests, or battery metered recharge capacity tests.

 

[RegGuheert]

Actually, IIRC, when Nissan took a number of Phoenix area LEAFs to examine them for capacity lose last Summer, they did not use either capacity bar displays or gid counts. to determine available battery capacity, whether this is the precisely the same thing as "battery degradation" or not.

Nissan reportedly used measured battery discharge tests.

No, I'm talking about what the car does to figure out how many battery capacity bars to display. If if doesn't base it on Gids, then what does it use?

My point is that I agree that the Gids are likely WAY off, but if both cars THINK they have the same number of Gids, then why don't they THINK they should display the same number of bars of capacity, regardless of whether or not it is correct?

 

[edatoakrun]

Actually, IIRC, when Nissan took a number of Phoenix area LEAFs to examine them for capacity lose last Summer, they did not use either capacity bar displays or gid counts. to determine available battery capacity, whether this is the precisely the same thing as "battery degradation" or not.

Nissan reportedly used measured battery discharge tests.

No, I'm talking about what the car does to figure out how many battery capacity bars to display. If if doesn't base it on Gids, then what does it use?

My point is that I agree that the Gids are likely WAY off, but if both cars THINK they have the same number of Gids, then why don't they THINK they should display the same number of bars of capacity, regardless of whether or not it is correct?

I have not lost a capacity bar, nor have I ever monitored my LEAF's gid count, so I'm not able to make an informed comment, beyond to ask you:

Why should you expect both these inaccurate data sources to be entirely consistent?

 

[edatoakrun]

That there is even a topic on cooling the battery is a good indication of how badly Nissan screwed up by not providing a TMS... I'm very close to losing my second capacity bar and will not ever again consider any EV that does not provide some form of TMS!

Can't help but agree with you there, and this summer hasn't even happened yet! IMHO, it's going to be a blood bath!!

No "blood bath!!" will occur this summer due to whatever capacity loss LEAFs may display, or what actually occurs.

I expect you meant that phrase as innocent hyperbole, and you probably think it is harmless to parrot this phrase, which has been used ad nauseum by others on MNL.

I suggest you consider that an actual "blood bath" will actually occur this Summer, for the entire year, and for the foreseeable future, just has it has continued for the last several decades, due to America's dependence on petroleum fuels for transport, over land, air, and water.

So I think it is particularly offensive of you to denigrate the real victims of the real and continuing petroleum "blood bath", by using that phrase to refer to what is at a relatively minor inconvenience to you, in having to take advantage of the battery capacity warranty Nissan has offered you, on a car that has allowed you to reduce your own responsibility for the real "blood bath".

 

[RegGuheert]

I have not lost a capacity bar, nor have I ever monitored my LEAF's gid count, so I'm not able to make an informed comment, beyond to ask you:

Why should you expect both these inaccurate data sources to be entirely consistent?

In the face of the data here, I guess I shouldn't. Still it surprises me. Most algorithms I've ever been exposed to are somewhat comprehensible. OTOH, I haven't figured out how the climate control works, yet, either!

 

[TomT]

Oh for heavens sake! :roll:

No "blood bath!!" will occur this summer due to whatever capacity loss LEAFs may display, or what actually occurs.

I expect you meant that phrase as innocent hyperbole, and you probably think it is harmless to parrot this phrase, which has been used ad nauseum by others on MNL.

I suggest you consider that an actual "blood bath" will actually occur this Summer, for the entire year, and for the foreseeable future, just has it has continued for the last several decades, due to America's dependence on petroleum fuels for transport, over land, air, and water.

So I think it is particularly offensive of you to denigrate the real victims of the real and continuing petroleum "blood bath", by using that phrase to refer to what is at a relatively minor inconvenience to you, in having to take advantage of the battery capacity warranty Nissan has offered you, on a car that has allowed you to reduce your own responsibility for the real "blood bath".

 

[cwerdna]

FWIW, I downloaded the Infiniti M Hybrid (which uses a lithium ion battery) manual via https://owners.infinitiusa.com/iowners/navigation/manualsAndGuides" onclick="window.open(this.href);return false; and confirmed that not surprisingly, it has a battery fan and intake in the interior, just like the defunct (Toyota HSD-based) Altima Hybrid, which uses NiMH.

Not surprisingly, every hybrid I know of has at least a battery fan and Ford (at least on their Escape Hybrid) went a step further w/a separate AC evaporator coil to go w/their battery fan.