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Discussion Starter #1
Some History of Car and charging history:
My car is 30kwh registered in October 2017 with 36000 miles on the clock. The previous owner bought the car from KIA (ex demo) with 8000 miles. He has a 7kwh charger where he used to charge the car on Economy 7 hours. However in the last 3 months of his ownership. his mileage increased to 200 miles day and this meant he had to charge it on a Chademo on the way back (he sold EV to me in May and bought a fossil car as he was fed up with charging on the motorways). I just use granny charger from our other car (Outlander PHEV), and I do less than 125 miles a week, so 1 charge per week.

I plugged a KONWEI odb2, and got the following figures from Torque pro:

%SOH = 100%
%Lost = 0%
Actual Battert Capacity = 30kwh

I am obviously happy that there is no apparent degredation, but find it hard to believe the 100% figure. It seems to be common on 30kwh, but not in the 24kwh which do seem to show some degradation. I know the car is newer but still is odd.
 

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Discussion Starter #3
Thanks James, that kinda makes sense. As most ev cars manuafacturer state actual capacity, and Hyundai KIA state actual available.

Does 100% SOH mean the 33kwh battery hasn't yet degraded below 30kwh usable
OR
Is actual battery bigger than 33kw?

I had no reason to check I am getting over 155 miles in Summer, other than opportunity as I needed to check the %SOH on my wifes 2016MY Outlander Phev (its %SOH 79%)
 

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I have monitored the life cycle of my 30kWh MY2018, awaiting end of lease collection, now at 22k (was meant to be 30k ... ) by means of measuring any ~10%-to-100% charges, and recording that for the duration of ownership.

The amount of energy required to recharge this car has remained constant throughout, within any measurement inaccuracy.

According to range, energy in and energy out, there has been zero detectable battery degradation.

My understanding was that these cells are actually taken to quite high [real] SOC at 100%, higher than most makes of EV, so I was presuming some degradation might be observable by lease end, but, nope, nothing.
 

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I think when charged to 100% you have access to the useable 30kWh. Not sure Kia have said what the total pack size is but 32.5kWh has been put out there on this forum before, so a 2.5kWh buffer. If true, that would mean a slightly smaller buffer than the 27kWh which had a 3kWh buffer.
 

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Yes, Kia themselves originally stated it was a smaller buffer than 27kWh.

They said that they increased capacity from 27kWh to 30 by; adding in 4 extra modules, from 96 serial to 100, and reducing the overhead buffer.

AFAIK, by the information they gave, the cells remained the same.

They said there were additional efficiency gains in the electronics, IIRC.
 

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Discussion Starter #9 (Edited)
Found by looking at other forums that cells were updated from E375 to the E400 in the 30kwh (so 37.5Ah usable in 27kwh and 40Ah usable in 30kwh). No one is still 100% sure (other than KIA who have never stated it) what the actual capacity is?

So as well as 4 extra cells and the extra 2.5 Ah per cell there is overall slightly over 11% extra capacity.

Useful thread but no concensus either: What is the total capacity of the MY2018 battery. - Kia Soul EV Forum
 

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Discussion Starter #10
I charged to 90% to today on a granny charger, as various posts in seem to recommend. i.e. don't let the chtual arge fall below 5% some say 10% 20%. As all of this is meant to slow down battery degradation... i.e. %SOH. Some say charge to 100% once a month others say 100% once every 3 months.

Its all very confusing?
Is there any real science behind this?

A lot of whats out there seems to hearsay.
Surely EV manufacturers manage this with the difference between real and usable capacity.
There are lot of posts from People who charge every day report showing no degradation. Though mostly point to the number of bars (and in the Leaf case it show 12 bar till battery reaches %SOH=85)
Rapid charging is said to be not good for the battery, as it raises the temperature and thus damaging the battery. I think KIA stop it charging above a certain figure. Though this may be as its very slow to charge after 90%.

What are the Soul EV owners actual findings? What are you charging routine (assuming your daily commute doesn't need 100% charge) ?

Living inside the M25 rules out extereme heat 🥵 or extreme cold 🥶 (Luckily no one lists persistant rain of having any effect)
 

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My reading around suggests that the worst horror stories are from cars which have no battery cooling (I understand some/all Leafs and early Soul EVs are affected). Soul EVs which have a fan unit in the boot (in the space where a spare wheel would have been fitted), should be better-off. However, the air which is circulated is cabin air, so if you are recharging on a hot day with the car in bright sunshine, the benefit would be limited (I'm assuming the fan runs when required during charging - someone may know for sure?).

I live in a small island, so my journeys are short. I try to recharge from 30% (sometimes 20%) and and aim to add 50%, so up to 70% or 80%. To do that, I have to estimate and set the charging times, as the % cut-off feature was deleted from later models :mad:.
 

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Discussion Starter #12
Thanks Ian for your reply

So the idea is not to get the batteries too hot, as this is what degrades them the most. My charging will mainly be at late evening/night time so, the outside temperature should be cooler and the cabin should be cooler too.

Is the fan recirculating the air from cabin only or does is take air from outside too?

Does charging on a granny charger produce a lot of heat?

Its is a shame that they removed the % cut-off feature as that would elimated the need to guess timer. I know some smart chargers can do this too. in my last charge the timer guess was badly micalculated. Tried to get 90%, ended up with 74% 😕. Will add 2 hours to the timer to see if I that get closer to 90%.

I talked to the previous owner. He had economy 7 and 32a home charger, so always set the timer for that and charged to 100% every time, but he needed the range.
 

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Is the fan recirculating the air from cabin only or does is take air from outside too?
Don't think so. The air intake is under the front seats.

Its is a shame that they removed the % cut-off feature as that would elimated the need to guess timer. I know some smart chargers can do this too. in my last charge the timer guess was badly micalculated. Tried to get 90%, ended up with 74% 😕. Will add 2 hours to the timer to see if I that get closer to 90%.
The onboard charge scheduler allows for % cut-off. I see 80% and 100% options.
 

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Is the fan recirculating the air from cabin only or does is take air from outside too?
My understanding is that cabin fan does not run.

Does charging on a granny charger produce a lot of heat?
A lower level of heat, because the charge rate is so low (only 10A), but, of course, it goes on for a longer time to get the same energy into the battery. But the lower level gives more scope for the battery ventilation and natural heat loss, as well as less stress on the battery. This is why the high-speed dc chargers should be avoided unless essential.
 

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No 80% option on my 2018 30kWh model. Is yours an earlier model, or is there some hidden facility I have yet to find?
Mine is earlier, yes. I'd be surprised if Kia removed this from later models. After all, it is just software.
See photo of the screen:
132189
 

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Discussion Starter #17
I have 30kwh too and the option is there but when when enter into setting screen all you can do is set start time but 100% cannot be changed
 

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Yes, they have removed the 80% option, apparently because the rules for evaluating the standardised economy data. would have resulted in a quoted range based on the 80% charge. Madness!
 

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Discussion Starter #20
Has anyone else read this from mykiasoulev forum, Jejusoul posted a link to papers for E400 battery cell (ones in 30kwh).


Amazing facts about life expectancy and degradation. They tested the E400 cells, by having 4 charge cycles to 100% at different temperature for 56 weeks (so 1568 cycles).
at 25C SOH=92.5%
at 35C SOH=86.6%
at 45C SOH=80.8%

The final conclusion was that at 45C it will take 2000 charging cycles to reach 80%SOH, but at lower temperatures it is expected to be better than that (and of course worse at higher temperarture)

Say by taking the worst case example for single charge is 105miles (ev database) * 80% (lead foot) * 90% (charge) = 75miles

So if 1 charge = 75 miles
@ 2000 charges the expected miles would be 150,000

If its really at 80% SOH at 150K miles that would be amazing. In my case it is all arbitary as that would take me another 14 years to get there, and much as I do love the car, I cant see me keeping more than 5 years.

Another nugget was
The 100% DST Discharge capacity with DST power of 400W/kg is 40.8Ah on average.

So the real buffer maybe really small (on average), but if they were chaged to 100% and still performed so well may have pursuaded KIA to go for the smallest buffer in any EV to date.

I have skimmed a lot so probably got a lot wrong,
 
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