Speak EV - Electric Car Forums banner

1 - 20 of 872 Posts

·
Registered
Joined
·
771 Posts
Discussion Starter #1 (Edited)
*** Xaccers links to Google sheets for data entry and up to date graphs below. This supersedes the original graphs I was maintaining. Cheers Xaccers!***

Xaccers wrote:
"In response to the chart showing faster degradation for 30kWh batteries, I've created the following if people with LeafSpy in the UK would care to add their figures:

30kWh Leaf
Data entry form: 30kWh Leaf age and health
Chart of results: 30kWh Leaf age and health


24kWh Leaf
Data entry form: 24kWh Leaf age and health
Chart of results: 24kWh Leaf age and health

It also includes Hx figures if you have them (currently trying to get confirmation on the 30kWh 2 year old leaf with 99% SOH but 45% Hx!)"

Simon
 

Attachments

·
Registered
Joined
·
466 Posts
Gen 2
March 2015
9025
95%
QC 112
L1/L2 221

One point to note though. Almost all of my L1/L2 charges are carried out overnight on the timer. I've noticed that this counter increases by 2 for each charge. It counts the 1 second after plugging in before the timer shuts it off. Then it counts again when the real charge actually starts. So the actual number of L1/L2 charges would be nearer to 110.
 

·
Registered
Joined
·
771 Posts
Discussion Starter #4 (Edited)
Here's the plot of the data I have so far. Quite a good correlation of SOH with age I think, considering there are lots of other factors in the mix. Compared to some data from early USA cars I found, we can expect batteries in the UK to last twice as long :)
 

Attachments

·
Registered
Joined
·
6,776 Posts
This was the first three months on mine:

196 miles and 0 months = 65.19 Ah, 99% SOH, 99.83 HX
992 Miles and 1 month = 66.79 Ah, 100% SOH, 105.95% HX
1963 miles and 2 months = 67.26 Ah, 100% SOH, 109.16% HX

I can't find the spreadsheet with the later ones.
 

·
Registered
Joined
·
4,259 Posts
Nice graph, but it needs to be a surface plot with a 3D graph with mileage as the third axis in order to determine if age or miles is dominating SOH.
 

·
Registered
Joined
·
4,259 Posts
It is a crude measure but the year to year summer seasonal best on the GOM is another indication (if not using LeafSpy). Last year GEN2 at 6 months old GOM best on 106 miles, (1600 miles driven) this year 102 on the GOM at 18 months (5800 miles driven). About a 4% annual drop which seems to be on trend. Looks like BEVs are use or lose. Not good for small annual mileage drivers. It makes battery depreciation at 4% per annum of a replacement costed £5000 running 4200 miles a year twice the cost of the electricity per mile.

Does this mean the second hand market should value and price on SOH more than mileage?
 

·
Registered
Joined
·
771 Posts
Discussion Starter #10
We'd need a LOT more data to get a meaningful surface plot. The data we have would give a wiggly line in XYZ, not a surface.
I have done a plot of miles vs SOH: not such a good fit on a log best-fit rather than linear. Here we see more of a difference between Gen 1 and 2 perhaps-
miles-vs-SOH-July16-v1.jpg
 

·
Registered
Joined
·
29 Posts
Gen 1, purchased November 2012
don't have leafspy so not sure SOH however
lost one battery bar Feb this year at 52,826 miles.
I was amused to see GOM displaying 96 miles (Eco mode) on 16th July.
IMG_5451.JPG
Passed 60K at the weekend.
Not counted how many or what type of charge but it gets plugged in most nights for a 100% charge for next days commute.
 

·
Registered
Joined
·
6,776 Posts
These are from my Gen1. It was registered May 2012, but I found out it was built about a year earlier.

Date/Time,AHr,Hx,Odo(km),QC,L1/L2,Ambient,SOH
09/12/2014 19:07,609292,84.27,9596,12,375,17,92
10/29/2014 18:31:45,603979,82.38,12267,17,458,7,92
11/24/2014 18:46:23,601814,81.93,14019,26,519,2,91
12/18/2014 23:02:02,604897,83.7,15844,35,583,11,92
 

·
Registered
Joined
·
6,776 Posts
And these are from my Gen2. Built 22nd December 2014

Date,Ah,Hx,Odo(km),QC,L1/L2,SOH
01/21/2015 18:46:25,651907,99.83,315,1,11,99
02/13/2015 7:15:37,673620,107.59,1773,3,64,100
03/03/2015,672573,109.16,3159,7,109,100
04/27/2015 18:17:40,673620,103.88,6441,17,210,100
06/02/2015,673620,103.88,6441,17,210,100
06/29/2015 18:41:07,650010,99.48,9858,35,294,99
08/04/2015,673620,104.86,12729,52,367,100
09/09/2015,673620,103.88,6441,17,210,100
09/09/2015,629867,96.82,14565,63,427,96
07/11/2016,613909,94.58,30610,141,855,93
 

·
Registered
Joined
·
1,913 Posts
30kWh Leaf. Delivered December 31st 2015

SOH 97%,
Hx 92.36,
AHr 77.47,
5252 miles,
Qc 16,
L1 427 (I think this number lies)
 

·
Registered
Joined
·
771 Posts
Discussion Starter #18
Gen 2
March 2015
9025
95%
QC 112
L1/L2 221

One point to note though. Almost all of my L1/L2 charges are carried out overnight on the timer. I've noticed that this counter increases by 2 for each charge. It counts the 1 second after plugging in before the timer shuts it off. Then it counts again when the real charge actually starts. So the actual number of L1/L2 charges would be nearer to 110.
That's a real shame from a data analysis point of view, so we've no way of knowing how many charges a battery has seen!
 

·
Registered
Joined
·
378 Posts
Nice thread and nice graphs. One small request, is there any way that you can put your most up to date graphs in the first post so that they are easy to find? I'm assuming that the thread could end up with lots of data! Thanks
 

·
Registered
Joined
·
956 Posts
Gen 2 Dec 14.

I have a few data points to help:

7/15 3,593 miles, AH 59.63, SOH 91%
8/15 4,101 miles, AH 59.42, SOH 90%
5/16 15,230 miles, AH 60.18, SOH 89%
7/16 19,013 miles, AH 59.59, SOH 89%

The charge counter does not count cycles, and double counts when using the timer. So worthless for our purposes.
We can use miles as a reasonable alternative (only if comparing like size batteries). Assuming an average 4.3 miles per kW and an average pack usability of 20kw (for 24kw pack).
Gives you approx 116 cycles per 10,000 miles.
 
1 - 20 of 872 Posts
Top