osbornab
Posts: 2
Joined: Wed Nov 24, 2021 7:07 pm

Slow Level 2 charging

Wed Nov 24, 2021 7:10 pm

2015 Kia Soul EV. 2nd owner and no problems to date. About 1-2 months ago max charging speed on Level 2 (240v) went down to 7.2 amp (1.7 kw). I have tried 2 different EVSEs to confirm that wasn't the problem. There are no CEL codes. The battery is only 1 year old as it was replaced under warranty given previous degradation; new battery is reporting a very good SOH. Has anyone else seen this?

IanL
Posts: 236
Joined: Tue Feb 18, 2020 12:57 pm
Location: Jersey, English Channel Islands

Re: Slow Level 2 charging

Thu Nov 25, 2021 12:46 am

This sounds like a BMS problem. The car signals the charger the level of current it wants, and it seems to be getting that wrong, sending the wrong signal on the CP line. Apparently, the early BMS are rather unreliable, so you should get a replacement under the warranty.

If you want to look up the detail, https://en.wikipedia.org/wiki/SAE_J1772. Although the article is for the Type One connector, the control protocol is the same for Type 2.

notfred
Posts: 561
Joined: Thu May 07, 2015 2:28 pm

Re: Slow Level 2 charging

Thu Nov 25, 2021 6:12 am

I suspect the OBC rather than the BMS. If the BMS wasn't accepting more than 1.7kW then you would have problems with regenerative braking. You could confirm by trying to DC fast charge as that goes straight to the BMS and battery, not involving the OBC at all. It doesn't really matter, if you are seeing the same issue on multiple different EVSE then the car needs to go to the dealer anyway.

FYI It's the EVSE that signals the current available to the OBC on the CP line. The car then just takes as much current as it wants up to that limit (and the Soul EV has a 10% margin for additional safety).

osbornab
Posts: 2
Joined: Wed Nov 24, 2021 7:07 pm

Re: Slow Level 2 charging

Fri Nov 26, 2021 5:44 am

Thanks for the insights. I will take it out today to test dc fast charging, but a problem with the OBC does make sense. There are no local dealers in my region that repair EVs so a repair will involve transporting the vehicle 200 miles away. If there were a few more DC fast chargers on I40 in TN I could probably make the drive, but they are still sparse in the South around TN and MS.

notfred
Posts: 561
Joined: Thu May 07, 2015 2:28 pm

Re: Slow Level 2 charging

Fri Nov 26, 2021 7:24 am

One other thought as you are down in the south and it may be warm. If the DC fast charge is also very slow or refuses to start, see if the fan in the trunk floor is working properly - it should kick up in speed when DC fast charging to keep the battery cool. If you have an OBDII bluetooth dongle and an Android phone then you can use the Soul EV Spy or EV Watchdog apps to check on the battery temperature and fan speed. The BMS may be limiting the charging rate to keep the battery cool if the fan isn't working properly.

IanL
Posts: 236
Joined: Tue Feb 18, 2020 12:57 pm
Location: Jersey, English Channel Islands

Re: Slow Level 2 charging

Fri Nov 26, 2021 1:58 pm

Does the 2015 model have the fan in the trunk?

notfred
Posts: 561
Joined: Thu May 07, 2015 2:28 pm

Re: Slow Level 2 charging

Fri Nov 26, 2021 7:42 pm

I believe all the first generation have the fan in the trunk to draw the air through and cool the battery. The 2nd generation have a liquid cooled battery

IanL
Posts: 236
Joined: Tue Feb 18, 2020 12:57 pm
Location: Jersey, English Channel Islands

Re: Slow Level 2 charging

Sat Nov 27, 2021 1:08 am

Yes, that's true. I don't know where I got the idea it was only introduced in 2017. https://www.kia.parts/v-2015-kia-soul-ev--plus--electric/electric-propulsion-system--cooling-system Item 5.

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