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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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Discussion Starter · #1 ·
Hi all - I’ve just taken delivery of a Kona, and I’m trying to educate myself about the battery heating and the effect of the charging rate.

Essentially, I’m trying to find out roughly how low the SoC needs to be on arrival at a charger to make it worthwhile using an ultra rapid if the outside temperature is, say, 0°C or 5°C or 10 °C.

I’ve posted the thread below in the Kona section, but just linking to it from here in the hope that the higher activity in the eNiro section might give rise to some additional advice. Many thanks 🙏

 

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #3 ·

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #4 · (Edited)
I found this video particularly useful and quite positive. Seems to indicate the 'coldgating' is only potentially going to be an issue if the ambient temp is nearer to 0 degrees. If it's nearer to 5 degrees (more usual for UK winter days I suspect) then it seems the car is able to keep the pack at or near to 25 degrees after the first slightly slower initial charge which will initially start at 56 or so kW.
 

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Kia e-Niro 4 MY20
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Yesterday (Jan 23rd) I did a trip and charged at the Shell Recharge Saxondale 100kW charger after driving about 170 miles. The outside temperature was 0°C and, when I plugged in with 9% charge on the battery, the Min battery temperature (the one that the allowed charge speed is based on) was 14°C. As a result, when I plugged in the charger started at 37kW as expected, quickly rising to ~40 and then ~50+kW once it crossed the first threshold at 15°C. Also when I plugged in, the battery heater came on to start to warm the battery pack. Looking at the monitored temps on the Car Scanner app, it looks like the heater temp tracks the battery temp since it was always about 10 to 15° more than the current battery temp as that increased up to 25*C. Anyway, it then took 25mins for all 4 compartments of the battery (and hence the min temp) to reach 25°C, by which time the state of charge was already ~35%. As soon as this threshold was crossed the charging power switched up to 75kW and stayed there until the ~52% charge threshold where it stepped to around 60kW, again as expected.

So though there is a battery heater (apparently a 2kW unit wrapped around the 'coolant' inlet pipe to the battery pack), it's action is quite slow so you really need to try to get the battery as warm as possible before you get to the charger to speed things up when you are there - so ideally charge after driving a long way giving you chance to do so. It's a great shame that the 'Winter mode', which does heat the battery up whilst you are moving, only comes into operation below -5°C. If this were not the case and it could be manually activated or you could set the temperature at which it activated, this could substantially shorten charging times when the outside temp is below around 5°C (since driving the car seems capable of maintaining around a 15°C heating effect at 0°C). This facility (with suitable safeguards) seems to me like something that could easily be added in a software update, but whether Kia will do so if enough people ask, who knows. So far this is the only real disappointment I have in the car since it has the capability to optimise Rapid charging times via the heater, but you just can't turn the damn thing on, unless you happen to live in a suitably cold country.
 

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ID3 1st & e-Golf
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Interesting read. I'm coming from posting about how inefficient my ID3 is in the cold. It seems the battery heater comes on every time the car is started when the temperature is below 8°C.
This gives very low efficiency figures on journeys of less than half an hour, maybe longer.
I had a Niro for just over a year and it was much more efficient on those shorter runs and as I rarely needed to charge the Niro while away from home I preferred it not to waste energy on heating the battery.

Maybe a setting on the dash would be needed to switch on heating to the battery when making longer runs.
 

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Kia e-Niro 4 MY20
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33 Posts
Interesting read. I'm coming from paying about how inefficient my ID3 is in the cold. It seems the battery heater comes on every time the car is started when the temperature is below 8°C.
This gives very low efficiency figures on journeys of less than half an hour, maybe longer.
I had a Niro for just over a year and it was much more efficient on those shorter runs and as I rarely needed to charge the Niro while away from home I preferred it not to waste energy on heating the battery.

Maybe a setting on the dash would be needed to switch on heating to the battery when making longer runs.
Yes, I can see 'compulsory heating' would also be annoying.
 

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #8 ·
Yesterday (Jan 23rd) I did a trip and charged at the Shell Recharge Saxondale 100kW charger after driving about 170 miles...
Thanks for this account, which is consistent with what I experienced when charging today in similar ambient temperatures (although starting from a slightly higher SoC). My account from today is here: Battery heating - how long does it take for the pack to...

Do you know what your battery temps were when departing from the origin, and had the car been on charge up until the departure time?

I’ve also been wondering whether having cabin heating on during the initial phase of charging may serve to increase the time required for the battery to reach the optimum temperature. Is it known whether having cabin heating on means that some warmth that would otherwise be going into the battery is diverted to the cabin, or is it an entirely separate system?

If it is potentially costly to have cabin heating on during the initial phase, then possibly a better option could be to 'overheat' the cabin in the 5-10 mins prior to arrival at the charger, so that then just the seat warmers alone are sufficient to be comfortable, at least until the battery has been warmed.
 

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #9 ·
Maybe a setting on the dash would be needed to switch on heating to the battery when making longer runs.
I haven’t personally experienced it myself, but it seems like Tesla have a fairly nice solution with the way they implement battery heating if you are navigating to a supercharger, as it doesn’t require manual intervention.

Although, I know some Tesla drivers have pointed out that the way it’s implemented is wasteful, and I don’t think (though could well be mistaken) that it’s possible to opt out of it.


A simple sub-screen in the EV screen on the eNiro/Kona/Soul showing the current battery temp. status and a button to turn on the battery heater would be be good.
 

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Although, I know some Tesla drivers have pointed out that the way it’s implemented is wasteful, and I don’t think (though could well be mistaken) that it’s possible to opt out of it.
Yes, one easy workaround in Tesla is to navigate to a place right next to supercharger, and Tesla will not preheat while driving to that supercharger.
 

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #11 ·
Yes, one easy workaround in Tesla is to navigate to a place right next to supercharger, and Tesla will not preheat while driving to that supercharger.
Oh yes, that makes sense.

Perhaps a good option for Hyundai and Kia to implement (plus Tesla and other manufacturers) would be to have a simple question pop up after a navigation destination is entered just asking the driver whether the battery should be "prepared for rapid charging" on arrival at that location. It could be a pop up that timeouts automatically and disappears after 5 seconds or so, with the default being not to. If selected, the car could then intelligently time commencement of heating based on the likely arrival time (taking into account traffic etc), much like Teslas do for superchargers. In addition, (including in Teslas) you would still ideally want a simple option to turn it on at any given time in instances when you don’t want/need to use navigation, or opt to use Waze/Google Maps instead.
 

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EVEZY code d55d6 *** Try my car cost calculator
'19 i3 120Ah / '20 Kona 64kWh / '21 e208
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3,159 Posts
Discussion Starter · #13 ·
Do Tesla and Hyundai heat the battery if it's cold when a preheat is set in the car?
Or do they just preheat when the car is started? If they do any ideas on the temperatures?
Tesla does when preheated via the app, not sure about Hyundai.
 
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