12% capacity loss in 9 months is "normal"

[mwalsh]

if you dont have a gidmeter, how can you measuring the percentage loss?

mike, I assume you are using some measuring tool. what is it?
and you also had a baseline measure when you bought?

Gidometer. Gary didn't start distributing them until last summer. But I think I bought one of the first and had it assembled by early August, so those were my earliest readings. I was pulling strong 97-98s pretty consistently, but 100/281 was a rare treat indeed!

This thread has some readings I managed to gather from various posts I've made. I didn't think to keep anything more formal and I don't know why I happened to keep readings from those particular dates without finding the theads they were posted to again. As you can see, a couple of oddball lows noted in October, but still able to pull 100 at least a couple of times:

http://www.mynissanleaf.com/viewtopic.php?f=30&t=8833&p=199576#p199576" onclick="window.open(this.href);return false;

 

[TomT]

I take it with a large grain of salt since we know how many times Leaf techs have been proven wrong or misinformed... I'm calling BS on this one.

He also said he drove a LEAF in TN and tested that one after a 100% L2 charge and it said there was 23.6kW h in that pack available.

Available? Sorry, I refuse to believe that one. Are you pulling our leg? Trying to do a one-up on evnow?

 

[LEAFfan]

He also said he drove a LEAF in TN and tested that one after a 100% L2 charge and it said there was 23.6kW h in that pack available.

Available? Sorry, I refuse to believe that one. Are you pulling our leg? Trying to do a one-up on evnow?
Ray

You can refuse to believe it, but since he has the 'tools' and has read quite a few LEAFs, I'll believe him. When it's new, and conditions are right, some can actually have almost 24kW h available. His instruments don't lie. If you think they do, then Ingineer's readings are wrong too.

 

[LEAFfan]

If his car only has 17.6 kWh capacity, that would suggest that a "100%" charge is getting him around 210 GIDs. But that should mean that he has lost 3 battery capacity bars, not just one, so something is definitely fishy here.

Are you serious? 17.6%kW h is right around 80%BC. The first capacity bar doesn't disappear until you've lost 15%. He already lost a bar, but it came back in a few minutes of driving. He will lose it again soon. But where in the world do get a loss of 3 bars? That would be a 27% loss. Go fish!

 

[TonyWilliams]

He also said he drove a LEAF in TN and tested that one after a 100% L2 charge and it said there was 23.6kW h in that pack available.

Available? Sorry, I refuse to believe that one. Are you pulling our leg? Trying to do a one-up on evnow?
Ray

You can refuse to believe it, but since he has the 'tools' and has read quite a few LEAFs, I'll believe him. When it's new, and conditions are right, some can actually have almost 24kW h available. His instruments don't lie. If you think they do, then Ingineer's readings are wrong too.

Honestly, this is just fruit cake talk.

 

[Herm]

Perhaps it was 120° F when the tech took those readings...

 

[TonyWilliams]

Perhaps it was 120° F when the tech took those readings...

On somebody's frontal lobe.

 

[LEAFfan]

Honestly, this is just fruit cake talk.

Honestly, you're not very nice. You always seem to 'know it all' Tony. Some day you will realize that other people know some things too, and you'll be eating that fruitcake (one word btw). I'll let the tech know what you think of his skills and readings if he hasn't already read (said he visits here) your egotistical drivel.

 

[TomT]

I'm with Tony on this one...

Honestly, this is just fruit cake talk.

Honestly, you're not very nice. You always seem to 'know it all' Tony. Some day you will realize that other people know some things too, and you'll be eating that fruitcake (one word btw). I'll let the tech know what you think of his skills and readings if he hasn't already read (said he visits here) your egotistical drivel.

 

[TonyWilliams]

I'm with Tony on this one...

Honestly, this is just fruit cake talk.

Honestly, you're not very nice. You always seem to 'know it all' Tony. Some day you will realize that other people know some things too, and you'll be eating that fruitcake (one word btw). I'll let the tech know what you think of his skills and readings if he hasn't already read (said he visits here) your egotistical drivel.

I'm not trying to be "nice". I'm just sticking to facts. There is not 23.xxx kWh "usable" in that battery. There was never 28.8, no matter who said it. Simple fact. Your tech is wrong. I'm not good at polishing turds, and I see no reason to start now.

We know that a Gid is 80 wattHours, as published by Nissan, and 281 of them gets on 22.5kWh. Then there are losses to make that energy "usable" down to about 75 wattHours per Gid; about 21kWh.

Sorry if that doesn't sit well with you, or your tech. The fact that your tech works for Ecotality doesn't inspire confidence with me, based on the multitude of broken Blinks.

I've spent a lifetime in industries where not challenging data that seems off might get me or a whole lot of others very dead. I don't have much patience for it. I have less patience when the clearly AFU data is then blathered about and defended. It's wrong. Move on. Get the right data. End of issue. Next.

Your comments concerning Ingineer are absolutely out of line. He provides very well researched data, and backs it up, over and over. Obviously, if we're comparing data and information from Ingineer or your clearly wrong tech who works for a company with questionable technical prowess, I know which one I'll believe.

 

[planet4ever]

I'm with Tony on this one

I think most of us are. Just apply a little common sense. If someone really had 23.6kWh usable, they could drive 100 miles at 4.5 m/kWh while leaving 1.4kWh for lighting, electronics, and climate control. That is a very generous allowance (at moderate temperatures), yet I don't recall anyone who has made 100 miles with less than 5 m/kWh.

Ray

 

[Ingineer]

If anyone in the SF Bay Area notices lost capacity or loses a bar, I'll be happy to check out the loss with LEAFSCAN so we can get some hard numbers.

-Phil

 

[mwalsh]

If anyone in the SF Bay Area notices lost capacity or loses a bar, I'll be happy to check out the loss with LEAFSCAN so we can get some hard numbers.

-Phil

Phil. When you get ready to ship the first batch of retail LEAFSCANs...don't forget your old pal mwalsh!

 

[tomsax]

I recently compiled data from 20 Roadster owners to see how battery capacity varies over time and miles. Here's the graph for capacity over miles:

And the graph of capacity over time:

The Roadster batteries are a different chemistry, different packaging, and different temperature management, so it's not a prediction of what Leaf owners can expect to see. Still, I think it's interesting that there is more variation between cars than there is over the best fit trend lines over 3 years and 30,00 miles.

Full details are here:

http://www.saxton.org/tom_saxton/2011/12/tesla-battery-capacity-aging.html

 

[Herm]

Thanks Tom, it would be nice if Tesla shared their data..

 

[DaveEV]

I recently compiled data from 20 Roadster owners to see how battery capacity varies over time and miles.

Nice data. Looks like Tesla battery packs are degrading at less than 1% / year and 1% / 10,000 miles so far.

It looks like Roadsters are going to by far exceed Tesla's prediction of 70% capacity remaining after 5 years / 100k miles - that must have been a worst case scenario.

What targets does the Tesla BMS have in regards to temperature / SOC?

 

[jguenst]

I believe Herm is correct some of this lose is from day one. Just got a new leaf a week ago. 61 AHr vs the 66 that is should be