Kish
Posts: 23
Joined: Mon Jan 29, 2018 11:56 pm
Location: SoCal, CA

Re: 2015 Soul EV: My Battery Replacement Story

Fri Apr 13, 2018 9:33 am

I can see how it can be confusing. The SOH values are something that we compute locally based on the PIDs the car provides-- it doesn't mean its 100% accurate. As JejuSoul mentions in the BMS thread:
The diagnostic data provided by the BMS does not include the SOH. It only has the min and max deterioration data from the total capacity.
After nearly 3 years of monitoring this data we were able to conclude that the SOH number as checked by a Kia service tech is actually a computed value. It is the average of min and max, taken away from 110. At Kia service any number greater than 100 is shown as 100%.


Furthermore:
For the next two years you will have to ignore these 'false' positives.
In the graphic above SOH is really 100%, SOH in kWh is really 27kWh and Lost SOH is really zero.


So in my case, SOH is really 100% (at 110% shown), SOH in kWh is really 27 kWh (at 29.7 kWh shown), and the Lost SOH is really 0% (at 10% shown). Remember that with my old (original) battery pack, Torque was showing anywhere between 79.4% to 91.7% SOH, even though the actual value measured by the dealership was 66.5% SOH.

Now these values have changed in Torque (after the DCFC experiment), I'm guessing that the actual values have also changed to "something" below 100% SOH. Think of these as "relative" measurements.
2015 Soul EV+ | 39k miles
2017 Bolt EV Premier | 28k miles

Kish
Posts: 23
Joined: Mon Jan 29, 2018 11:56 pm
Location: SoCal, CA

Re: 2015 Soul EV: My Battery Replacement Story

Fri Apr 13, 2018 10:05 am

alexank wrote:
@Kish Thankyou for making the time to share this very interesting reading

A couple of things spring to mind
I wonder if the previous owner overheated the battery regularly as well by doing regular long trips, the cumulative result may have been the degradation you inherited.

I also wonder if yours is a one off, maybe the fan etc in the boot is faulty, air flow restricted etc?


YW! Yes, I think your theory about how the previous owner used the car is reasonable. As mentioned in the battery aging thread:

JejuSoul
...when you do get the new battery and want it to last a long time, avoid regularly driving fast for long distances.
It's fine once in a while when you're in a hurry to get to the airport for instance. But the stress put on the battery by daily commuting 55 miles on the freeway at 75mph is going to age the battery fast.


Higher speed = more amps pulled from the battery pack = more heat build up = battery deterioration.

I'm guessing most people reporting on this forum come from countries with slower highway speed limits and/or live in rural areas. That's why there hasn't been too many reports of degradation. I've noticed that most of those that do report deterioration is from AZ/CA! (where people drive 75 - 80mph regularly, not to mention higher ambient temps). I see my battery temps reaching 105F+ (fan level 5) easily just driving at highway speeds for a while, even without any DCFC sessions. Are others seeing this? Maybe I should check that cooling fan in the trunk.
2015 Soul EV+ | 39k miles
2017 Bolt EV Premier | 28k miles

JejuSoul
Posts: 1096
Joined: Wed Jul 08, 2015 6:47 am
Location: Jeju
Contact: Website

Re: 2015 Soul EV: My Battery Replacement Story

Sat Apr 14, 2018 11:40 pm

ZuinigeRijder wrote:I do not understand the "Lost SOH %" and "Lost SOH kWh". If would expect this to be 0.5% and 0.1 kWh (27 kWh = 100%, 29.7 kWh = 110%)...

Everything is correct. I will answer this on the Torque thread. - Setting up Torque to show BMS data
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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