Elmil
Posts: 142
Joined: Mon Oct 26, 2015 9:46 am
Location: Sweden

BMS software update

Wed Sep 28, 2016 9:03 am

Yesterday I had my car in for 3:rd service after 45000 km in 17 months.

The SOH (State Of Health) value for the high voltage battery had changed. It is now 99.2%
I was hoping to discover a corresponding change in the BMS OBD2 data, but unfortunately there is nothing to find. It's annoying, because the SOH is the only value on the battery report that is not identified in the OBD2 data.
On the other hand, the deterioration values are not present in the battery report, so maybe the SOH is calculated on the fly using some algorithm involving the deterioration values.

My det.values are now: Max 11.5%, Min 10.0%.
Probably need more GDS/KDS readings to figure out the algorithm (if any..) I only had a battery report at 15000 km service, and at that time no OBD2 logging. :(

Anyone else having other than 100% SOH yet?
Last edited by Elmil on Mon May 08, 2017 7:29 pm, edited 1 time in total.
Kia Soul EV 2015 / 115,543 km Sold
Kia Soul EV 2019

JejuSoul
Posts: 1612
Joined: Wed Jul 08, 2015 6:47 am
Location: Jeju
Contact: Website

Re: SOH change

Wed Sep 28, 2016 7:17 pm

Elmil wrote:On the other hand, the deterioration values are not present in the battery report, so maybe the SOH is calculated on the fly using some algorithm involving the deterioration values.
SOH is calculated within the BMS itself. That value must be on the CANBUS. Can you post a full list of the hex codes returned from the BMS on the BMC Compare page - https://docs.google.com/spreadsheets/d/ ... 1174560131

See - http://www.skbattery.co.kr/what/bms.aspx : This link and image seem to be dead. Am looking for a replacement.
Image

Also note there are two versions of the battery report. (possibly relating to the difference between GDS and KDS - or maybe relating to a difference in the English vs German software)
Elmil - what language is the software used in Sweden, and do you know whether it is GDS (windows based) or KDS (Android based).

In this German version deterioration values are not present in the battery report. Alkl who originally did the CANBUS decoding on the SoulSpy thread used this version which is why he did not find the deterioration values.

SOH (Gesundheitsstatus) nach 34'000 Km

Image

This GDS (English) version does have the deterioration values. I found the deterioration values after Alkl had done all the hard work merely because I used the English version and he used the German. (Update: not necessarily true - there are also English versions that don't show the deterioration numbers.)

Image
Last edited by JejuSoul on Tue Apr 11, 2017 6:16 pm, edited 1 time in total.
The codes for using Torque Pro can be found by clicking the link in the website icon under my user name on the left.

Elmil
Posts: 142
Joined: Mon Oct 26, 2015 9:46 am
Location: Sweden

Re: SOH change

Thu Sep 29, 2016 8:36 am

JejuSoul wrote:Can you post a full list of the hex codes returned from the BMS on the BMC Compare page - https://docs.google.com/spreadsheets/d/ ... 1174560131
Done!
JejuSoul wrote:Also note there are two versions of the battery report. (possibly relating to the difference between GDS and KDS - or maybe relating to a difference in the English vs German software)
Elmil - what language is the software used in Sweden, and do you know whether it is GDS (windows based) or KDS (Android based).

First time I got the battery report they used GDS. This time I went to a new service provider, and now the report came from KDS. They are both in English and none of them include the deterioration numbers.
Kia Soul EV 2015 / 115,543 km Sold
Kia Soul EV 2019

JejuSoul
Posts: 1612
Joined: Wed Jul 08, 2015 6:47 am
Location: Jeju
Contact: Website

Re: SOH change

Fri Sep 30, 2016 5:36 am

-
Thanks Elmil.
I looked at your data and it seems the SOH is not one of the codes returned when we request values from the BMS.
I now suspect it is on the CANBUS all the time. Are you able to post the data from the C-Can tab.

I regret not being more thorough in photographing my own experience at Kia Service. Here is the only photo I have of my 100% SOH reading from GDS.
I didn't get a printed list of all the data.

Image

Here's a picture from Hyundai Service upgrading my test drive I oniq EV with GDS. (Hyundai and Kia use the same GDS software)
To get the BMS data you click the BMS icon..

Image
Last edited by JejuSoul on Tue Apr 11, 2017 6:20 pm, edited 1 time in total.
The codes for using Torque Pro can be found by clicking the link in the website icon under my user name on the left.

Elmil
Posts: 142
Joined: Mon Oct 26, 2015 9:46 am
Location: Sweden

Re: SOH change

Sat Oct 01, 2016 4:53 am

I made a new tab in the spreadsheet, named "C_CAN_Compare".

Some ID:s don't respond, but it's a starter..
Kia Soul EV 2015 / 115,543 km Sold
Kia Soul EV 2019

JejuSoul
Posts: 1612
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Location: Jeju
Contact: Website

Re: SOH change

Sat Oct 01, 2016 5:53 am

Thanks Elmil. SOH is still not apparent from your data, but I'll continue to look. I think it must be somewhere, rather than a value that gets created on the fly.
It's interesting to work on this data anyway. There are values like the odometer reading there which I have never yet managed to get into Torque.

In PID 4F0 bytes 5, 6 and 7 your value 06FE0 corresponds to 45,667.2km driven. (although you write 45,640km - do you know why there is a difference?).
The codes for using Torque Pro can be found by clicking the link in the website icon under my user name on the left.

Elmil
Posts: 142
Joined: Mon Oct 26, 2015 9:46 am
Location: Sweden

Re: SOH change

Sat Oct 01, 2016 6:31 am

It's accurate, I just had noted the odometer value before a trip today, then I made the final reading after I got home.

I actually already use some of these ID:s in my logger data:
200, 4F0 and 653 contain the DTE, Odometer and Outdoor temperature, respectively. It's very nice to have them together with the normal polled data, but it's a bit tricky (and slow). Also my PC software isn't optimized for speed, It's just a Python script... ;)
Kia Soul EV 2015 / 115,543 km Sold
Kia Soul EV 2019

Elmil
Posts: 142
Joined: Mon Oct 26, 2015 9:46 am
Location: Sweden

Re: SOH change

Thu Nov 03, 2016 11:09 am

Today I had my car to the workshop for the steering recall (which I think most of the world did last winter :? ).

Took the opportunity and asked for another battery report. The SOH had changed from 99.2% to 99.5%. So I checked the deterioration numbers from these two occations and think I may have found a feasible formula for the SOH computation! :D

Here's the data:

Code: Select all

Date   SOH      MaxDet   MinDet
27/9   99.2%   11.5%   10.0%
3/11   99.5%   11.2%    9.7%


We know that the SOH stays at 100% quite long, and the deterioration values are changing frequently when triggered by the right charging event. So I made the assumption, that if the SOH is computed from the deterioration numbers, it must actually start a bit above 100% for a brand new car. The instrument could display 100% though.

To get my two datasets fit in a common formula, I came up with this:

Code: Select all

SOH% = 110% - Average(deterioration)  =  110% - (MaxDet+MinDet)/2


If the SOH is calculated like this, it also means that in a situation of battery warranty at 70% SOH, the average deterioration would be 40%..

Side note:
The 110% baseline would correspond to a total energy capacity of 27kWh * 1.1 = 29.7kWh, or Amp capacity of 75Ah * 1.1 = 82.5Ah. This is just below what has been measured by the AVT test lab. Actually I think the cells were slightly over-speced by SKI for the test (4.3V max and 2.5V min), probably using the ABSOLUTE maximum and minimum voltages. I'm quite sure that SKI would never allow these extremes in any situation. For example, when I ran the battery flat this summer (on purpose), the HV battery was at 297V, which corresponds to 3.09V/cell.

Again, all this is still very speculative because of lack of data, but I think it makes sense as a starter point. The SOH formula should be easy to implement in Torque Pro too. And more data needed. ;)
Kia Soul EV 2015 / 115,543 km Sold
Kia Soul EV 2019

SoulEV2016
Posts: 572
Joined: Mon Jul 18, 2016 6:26 am

Re: SOH change

Thu Nov 03, 2016 1:37 pm

Image

Oh yeah, i like that.
Now, i can integrate this in the Torque Pro 004_CALC CSV.
Kia Soul EV 2016 Ultimate 27 kWh - Mountain hard driving (fast). Drain 1/3 of Battery after 32km. - Unlimited highway speed (153km/h at regulator).

JejuSoul
Posts: 1612
Joined: Wed Jul 08, 2015 6:47 am
Location: Jeju
Contact: Website

Re: SOH change

Fri Nov 04, 2016 6:38 am

Elmil, am glad your SOH has improved. This is not what I expected. But clearly it is a fact. What was your odometer reading at the last test?
I would like to wait for more data before being confident that there is a simple formula linking Max and Min deterioration to the the SOH.

Elmil wrote:The 110% baseline would correspond to a total energy capacity of 27kWh * 1.1 = 29.7kWh, or Amp capacity of 75Ah * 1.1 = 82.5Ah. This is just below what has been measured by the AVT test lab. Actually I think the cells were slightly over-specced by SKI for the test

No, the AVT tests we are using to state total capacity is 30.5kWh are from the 4 actual Soul EVs that are being tested at Phoenix. There is very little probability that these are over-specced. I ignore the value published in Vehicle Specifications and Testing Results 32.5kWh because that is greater than in the actual cars. It's probably just a typo because the Ah value is the same.

Compare the batteries of the 4 cars tested at https://avt.inl.gov/vehicle-button/2015-kia-soul
The codes for using Torque Pro can be found by clicking the link in the website icon under my user name on the left.

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