WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 5:17 am

LeftieBiker wrote:No, that's because replacement laptop batteries and cell phone batteries are very cheap and easy to self-install, and the weight of a TMS would be a problem for consumers. If laptop batteries were essentially permanently installed, there would be better cooling systems in them.


My laptop batteries are permanently installed, as are my cell phone batteries. OK, with special tools you can disassemble both and then glue back together. Not for the non-technical, to say the least. I've never seen a cell phone with a battery thermal management system. Or a laptop.

Now for some real reasons. How much battery power would be needed to keep the battery in the cell phone cool for a day? How much bigger would the cell phone battery need to be?

Why are there no warm blooded mammals much smaller than a mouse? Why does a bee humming bird (the smallest warm blooded bird) need to eat well over twice its mass every day... and still can't be warm blooded full time? And cooling is a harder problem than warming.

Heat loss/gain is proportional to surface area. Battery energy storage is proportional to volume. As an object gets smaller, the energy storage goes down faster than the surface area. Get small enough, and it gets harder to maintain at any temperature other than ambient. A laptop is not as thermally insulated as a mouse, has a higher ratio of surface area to volume, because it is thin, and needs to be cooled rather than heated.

Want a laptop or a cell phone with active cooling battery and similar operational time? It would be at least as thick as a brick. Larger battery, thermal insulation, cooling hardware, etc.

I can turn my cell phone off, and the battery will stay at almost the same charge level for months. Same with my laptop, if I shutdown. Same with my Leaf. If there was a TMS system? The shutdown time for a laptop or cell phone would be hardly longer than the operational time. The laptop would drain in a day. Leaf would be much better, would drain the battery in weeks, much as a Tesla will drain to bricked batteries in a few months.

Active cooling isn't free. I don't want it for my laptop or my car.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 5:23 am

camasleaf wrote:Just curious what cars and where?


One well documented example is the Ford Focus electric in Arizona.

https://avt.inl.gov/vehicle-button/2013-ford-focus
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
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Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 5:50 am

SageBrush wrote:Sure it is. A good TMS is a a great thing, everything else being equal.


Actually, not.

I live in a cool place. Assuming my Leaf had a TMS, and that the TMS started to cool at 86F/32C, it would have turned on 14 times in total in the past 2 years, according to my LeafSpy log. Most of the time for less than 2 C. For driving time, 1.7% of the time. I don't have logs for no-driving times, but none of the logs started at or above this temperature. The only way I've noticed such temperatures is a DCQC and a long drive.

If battery life halved on a 10C increase, I might have 1% or less improved battery life.

Hardly great, at best.

Why would I want this added cost, weight, complexity?

Why would I want this reduction in reliability?
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

SageBrush
Posts: 2913
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 7:35 am

WetEV wrote:Why would I want this added cost, weight, complexity?


To avoid this:

Image
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 7:58 am

SageBrush wrote:
WetEV wrote:Why would I want this added cost, weight, complexity?


To avoid this:


This is a chart of reported bar losses, not how far you can expect to drive before losing a bar. Having not lost a bar, my car isn't on it. As is every car that hasn't lost a bar.

I don't see anything there that makes me want a TMS. Active cooling would only be working less than 1.7% of my driving time, and probably less than 0.1% of total time. The gain in battery life would be microscopic.

I like it how Leaf batteries don't catch fire, unlike Tesla's batteries. Sure, gasoline is even worse.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

SageBrush
Posts: 2913
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 8:45 am

WetEV wrote:This is a chart of reported bar losses, not how far you can expect to drive before losing a bar.

Look at the chart again.

E.g., there is about an 80% chance a LEAF owner will drop a bar by the time they drive 40k miles.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 9:23 am

SageBrush wrote:
WetEV wrote:This is a chart of reported bar losses, not how far you can expect to drive before losing a bar.

Look at the chart again.

E.g., there is about an 80% chance a LEAF owner will drop a bar by the time they drive 40k miles.


Notice again that is a chart of currently reported bar losses. Leafs that have not lost a bar are not on that chart. My car is not on that chart, as I have yet to lose a bar. This is not how far you can drive before losing a bar. Those are two different things, unless all cars have lost a bar.

I'm past 40k miles, and perhaps a year or two or three and 10k to 30k more miles from losing a bar.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

SageBrush
Posts: 2913
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 9:31 am

WetEV wrote:
SageBrush wrote:
WetEV wrote:This is a chart of reported bar losses, not how far you can expect to drive before losing a bar.

Look at the chart again.

E.g., there is about an 80% chance a LEAF owner will drop a bar by the time they drive 40k miles.


Notice again that is a chart of currently reported bar losses. Leafs that have not lost a bar are not on that chart. My car is not on that chart, as I have yet to lose a bar. This is not how far you can drive before losing a bar. Those are two different things, unless all cars have lost a bar.

I'm past 40k miles, and perhaps a year or two or three and 10k to 30k more miles from losing a bar.

I understand your argument but there is no good reason to think it will apply here. Just look at the histogram shape.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

WetEV
Posts: 2370
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 9:43 am

SageBrush wrote:I understand your argument but there is no good reason to think it will apply here. Just look at the histogram shape.


My car is not on that chart. And when it gets put on that chart, I'm already past 40k miles. As is a co-worker's Leaf, a 2013 SV with almost 60k miles.

A TMS would not increase my battery life. My battery stays too cool almost all the time for active cooling to do anything.

As the co-worker doesn't QC, I suspect active cooling would do exactly nothing for his battery life. Yes, he has the option to do so, but has done so exactly once. Mostly just to try it out.

I'd rather not pay for active cooling, my battery life isn't improved by active cooling, and I'd rather not have a battery pack that catches fire like a T esla.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

SageBrush
Posts: 2913
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Possible Widespread 2018 Traction Battery Quick Charge Problems

Sun Apr 29, 2018 10:27 am

WetEV wrote:
SageBrush wrote:I understand your argument but there is no good reason to think it will apply here. Just look at the histogram shape.


My car is not on that chart. And when it gets put on that chart, I'm already past 40k miles. .


<<sigh>>
I know it is not. And when it is the bars are not going to change. There are too few of you to matter. You are in the 4% group.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

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