jcallan
Posts: 46
Joined: Mon May 11, 2015 9:24 am
Location: Cambridge, UK

Battery degradation

Tue Jun 23, 2015 12:30 am

Has anyone experienced any battery degradation yet? How is it shown on the display - does the % stop going up to 100%, or is it just that the range becomes lower?

The service manual has detailled procedures for dismantling the battery and, for example, replacing the heater wires. It doesn't cover individual cell replacement, but it would seem straightforward, and the diagnostic software can display the voltage/degradation of each of the 96 cells. So I think it should be possible to take the car to the dealer and say 'swap out the worst 10 cells' for a reasonable price. In the UK the battery is guaranteed to be above 70% for 7 years/100k miles, but I worry that the car might be less useful at 75% (say) than it is today.

mtndrew1
Posts: 296
Joined: Thu Oct 16, 2014 3:06 pm
Location: Los Angeles, CA

Re: Battery degradation

Tue Jun 23, 2015 10:21 am

I think it's too early to tell about degradation. I can't imagine there are many Soul EVs on the road yet with more than 15,000 miles.

In the US it's guaranteed for 10/100k to 70% and I expect it to be right about that level of degradation.

My particular car was used in the InsideEVs Soul range test http://insideevs.com/kia-soul-ev-range- ... 100-miles/ and I plan to duplicate this to the best of my ability next October on the one year anniversary to get an idea of what degradation is. I'll have about 15,000 miles on the car and it will have lived through one Southern California summer. I expect 5-10% degradation.

As another data point, AVTA just took delivery of four Souls for long term testing and you can follow along here http://avt.inl.gov/fsev.shtml

tractioninc
Posts: 202
Joined: Fri May 08, 2015 6:53 am
Location: Atlanta, GA USA

Re: Battery degradation

Tue Jun 23, 2015 11:52 am

jcallan wrote: I think it should be possible to take the car to the dealer and say 'swap out the worst 10 cells' for a reasonable price.


Industry precedent so far has not proven that to be the case. Individual cells are carefully matched during initial battery pack assembly. A similar skill-intensive and laborious process would be needed to carefully match used replacement cells to the 'healthy' but partially-consumed used cells in a customer's battery pack. In the short-term, I can't imagine car companies encouraging their dealer service centers to try this instead of simply replacing whole packs with new packs (or new intra-pack modules, in the case of cars like the BMW i3). There's not a viable market yet for private battery technicians as most of EV power units are covered by long and comprehensive warranties.
Kia Soul EV+, Porsche 928

iletric
Posts: 137
Joined: Thu Oct 16, 2014 10:07 am

Re: Battery degradation

Tue Jun 23, 2015 6:50 pm

mtndrew1 wrote:I can't imagine there are many Soul EVs on the road yet with more than 15,000 miles.
We're at 16,600. Nothing noticeable yet. I always watch what the car does on the same route over and over. I know exactly where I'm supposed to be at any time of my round trip (for lack of anything better to do while commuting).

If the range lags by 2-3 miles I call it car's bad day. If my combined mileage is 97 or even 101-102 that's the good day. It mostly depends on how cold it gets at night. I do see a clear correlation. I look forward to "tropical nights" later in September, what the starting range is gonna be. Presumably much higher. My starting point is usually 92-93, on warmer nights 95.

As for range loss, I always watch for signs of if by the first range bar drop - that's what happened with the Leaf. First bar range was the first thing that changed. So far it's holding at 13.4 miles or higher (and the 2nd one around 19-20). If I go faster it may be a little lower, 13 or so, even 12-something. Taken together, I see no range loss at this time at all. Which is very nice.

Now if Kia could fix how to access next music folder from my thumb drive. I really hate messing with it while driving, pressing 2 buttons and then turning the right knob, all that just to advance to the next CD folder. Real downer for me. Just hate it.

jcallan
Posts: 46
Joined: Mon May 11, 2015 9:24 am
Location: Cambridge, UK

Re: Battery degradation

Thu Jun 25, 2015 4:52 am

iletric wrote:We're at 16,600.


That's some serious mileage! We're only at 1,600... how long have you had the Soul EV?

mtndrew1 wrote:As another data point, AVTA just took delivery of four Souls for long term testing


Very interesting indeed... the service manual says (if I understand correctly) the battery state-of-charge is maintained between 5% and 95%, presumably rescaled to 0%-100% for display to the driver. Kia quote 27 kWh and AVT measured the actual capacity as 30.4 kWh. So Kia really are quoting usable capacity (that is, 95%->5% SoC), and their charge management strategy should result in good battery life. Good news. Look forward to your October test as well.

tractioninc wrote:simply replacing whole packs with new packs


Well, I guess that's a little more expensive, but essentially still quite reassuring. We're so used to the idea that an ICE can be fixed whatever happens to it that we don't worry much about it. With an EV it seems rather scary that you've got this huge block under the car that could stop working [well enough] and one tends to fear it could make the whole car worthless. But once you see inside the battery and realise the guys wearing overalls (and rubber shoes) can take it apart... not so bad.

tractioninc
Posts: 202
Joined: Fri May 08, 2015 6:53 am
Location: Atlanta, GA USA

Re: Battery degradation

Thu Jun 25, 2015 6:53 am

jcallan wrote:We're so used to the idea that an ICE can be fixed whatever happens to it that we don't worry much about it. With an EV it seems rather scary that you've got this huge block under the car that could stop working [well enough] and one tends to fear it could make the whole car worthless. But once you see inside the battery and realise the guys wearing overalls (and rubber shoes) can take it apart... not so bad.


Here in the US we've had mass-market electrified vehicles since the Honda Insight and Toyota Prius first went on sale a decade and a half ago. In the time since many more hybrid models have been introduced, from practically every automaker--even Porsche and Ferrari! Something like 3.5 million Prius' have been sold. Nissan has dominated pure-EV sales since 2010 with 180,000 Leafs sold. Tesla sales have passed the 75,000 mark. So we have many years and millions of miles of real world data of how electrified drivetrain components wear and require service and fail.

But they do fail differently than traditional cars. EVs drivetrains have few moving parts. Our gearboxes are single-speed units, so much less complex than today's 6-9 speed automatic, CVT or DCT transmissions. Our electric motors have a single major moving part. So it's the battery pack, charging unit, control unit and the software that runs them where all the complexity and expense really reside.

Diagnosing a controller or charging unit issue means tracing circuits and evaluating software code. Even isolating and servicing a battery pack issue requires tools and skills that don't exist in today's dealership service centers. It will take years for a new generation of specialty mechanics to be trained and deployed, so in the mean time OEMs have been replacing these major components instead of repairing them in the field.

Keep your car under warranty ;)
Kia Soul EV+, Porsche 928

irfca
Posts: 116
Joined: Sat Oct 18, 2014 1:14 pm
Location: Toronto, ON

Re: Battery degradation

Thu Jun 25, 2015 8:02 am

jcallan wrote:Has anyone experienced any battery degradation yet? How is it shown on the display - does the % stop going up to 100%, or is it just that the range becomes lower?

I've just passed 3 months and 10,000km (6,250 mi) and experienced my best range ever on my daily commute @ 101.5km using 52% of the battery ... which projects to 195km / 121mi total range ... I usually see a very consistent 165km / 103mi of range for my daily commute during spring/summer weather. I don't yet know why the range was better that one day ... I took a different route to/from work which avoids 1 steep hill, in favour of a longer slower rise ... I'll have to watch over the next few weeks to see if it happens again when I take that route. The most interesting part was, that extra range was with a 3rd carpooling passenger and A/C running.

... so no battery degredate yet! Not even a little.
Kia Soul EV Luxury Onyx/Inferno Red Pearl 2-Tone.
Ordered: 16-Oct-2014 - Delivered: 16-Mar-2015

iletric
Posts: 137
Joined: Thu Oct 16, 2014 10:07 am

Re: Battery degradation

Sun Jun 28, 2015 12:42 pm

jcallan wrote: how long have you had the Soul EV?
October 18 2014, about a week after it came out.

Regarding range: I've been noticing a slight change of condition, medically speaking. My a.m. 100% change now has been dropping to 90 miles instead of the usual 93 or even higher. Maybe it's a fluke but is hasn't been that cold at night.

I have upped my tires to 6 psi below max again, it was off by 2 psi. See if it helps to reset the car's range memory. My hunch tells me though the drop is for real. I've been through this before with Leaf. I must say that the 1st range bar drop is still holding at about 13.4 miles plus/minus 0.5 depending on speed I drive. Which is a good sign overall. It could also be Soul's particular range display mapping, so who knows...

UPDATE: Mileage now 17,700. Starting range in a.m. is now consistently 89-90, no longer 93-95 it was 10,000 miles ago. The nights are in high 50s, so this is not a good sign. I have to slow down now to 62 to maintain my 82-mile trip with a cushion of 7-9 miles.

I must add that our '14 Spark at 20,000 miles shows no range loss at all; a.m. range is 80-85 depending on night-time temp. Very consistent.

JejuSoul
Posts: 1639
Joined: Wed Jul 08, 2015 6:47 am
Location: Jeju
Contact: Website

Re: Battery degradation

Sun Sep 20, 2015 7:14 pm

jcallan wrote:Has anyone experienced any battery degradation yet? How is it shown on the display - does the % stop going up to 100%, or is it just that the range becomes lower?

Can someone confirm that it is the latter - the range becomes lower, but a full charge is still shown as 100%.

Am looking at the service manual which states -
SOC (State of Charge) : Available energy in the battery
SOC= [Dischargeable current] / [Battery rated capacity]

The wording 'Battery rated capacity'' could imply the original rated 27kWh that the car began with.
But I do not think this. I think it means the capacity that the battery has now.

I think there is a second metric SOH (State of Health) that gives the present condition of the battery.
The SOH is not displayed to us, and is not discussed in the manual, but I am fairly sure it exists.

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The codes for using Torque Pro can be found by clicking the link in the website icon under my user name on the left.

2016Electric
Posts: 179
Joined: Thu Sep 17, 2015 4:05 am
Location: Toronto, Ontario

Re: Battery degradation

Tue Sep 29, 2015 7:10 am

iletric wrote:
jcallan wrote: how long have you had the Soul EV?
October 18 2014, about a week after it came out.

Regarding range: I've been noticing a slight change of condition, medically speaking. My a.m. 100% change now has been dropping to 90 miles instead of the usual 93 or even higher. Maybe it's a fluke but is hasn't been that cold at night.

I have upped my tires to 6 psi below max again, it was off by 2 psi. See if it helps to reset the car's range memory. My hunch tells me though the drop is for real. I've been through this before with Leaf. I must say that the 1st range bar drop is still holding at about 13.4 miles plus/minus 0.5 depending on speed I drive. Which is a good sign overall. It could also be Soul's particular range display mapping, so who knows...

UPDATE: Mileage now 17,700. Starting range in a.m. is now consistently 89-90, no longer 93-95 it was 10,000 miles ago. The nights are in high 50s, so this is not a good sign. I have to slow down now to 62 to maintain my 82-mile trip with a cushion of 7-9 miles.

I must add that our '14 Spark at 20,000 miles shows no range loss at all; a.m. range is 80-85 depending on night-time temp. Very consistent.



hey - this was a while ago, but what's your range like now? Could there have been other factors that reduced range? (Driving and weather conditions)

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