Kona EV "Winter Mode" - defined and condensed

You are likely correct on all points and already know more about it than many of us here. Where the 35 kW number come from?
I left it on all last winter for lack of any better info. You can witness it's operation using Torque Pro, if required.

 

Noting that he doesn't mention a source for that information. I take his videos with a medium-sized grain of salt since he's a bit prone to speculation.

 

It sounds like the battery warmer is an option? If you don't have the 'battery warmer', is there another system for cold weather thermal management for the battery?

 

I'm sure this has been posted already before but here's a good article about the Kona EV's battery heating options:
https://electricrevs.com/2018/12/20/exclusive-details-on-hyundais-new-battery-thermal-management-design/

 

My thinking was that the heat from the warmer in motion, while an energy expense, nets a greater increase in power available for range than would exist in a ambient temperature cold battery. No?

 

Its an interesting thought but I have wonder when it actually does come on. I pretty much watch the battery care monitor most of time while driving. I have been driving with winter mode on with recent overnight lows in -25C range and day times highs around -15 to -18C and have yet to see the battery warmer come on while driving. A previous poster had indicated documentation that mentioned that it does not come on until -17C. I suspect that may be the actual battery temp not ambient. I have witnessed it come with the aid of torque pro while DC charging at -10C and I suspect it has also come on while the car was connected to shore power overnight.

 

Sorry, but I may not have been clear. I was talking about the electric battery warmer that the OP mentioned (on my 2020), being used while driving, and not any warmer to help with charging or while not in motion.

My question is whether the stated 2kW energy cost of running the electric heater while driving recoups more in the way of range than it costs.

 

I think if it did there would not be a switch. The tradeoff is performance over range.

 

I'd be good to know for certain....

 

I don't believe that range is affected significantly by battery temperature. Going back to the OP, the idea of running the heater while driving is to enable faster charging when you stop, and to prevent loss of power in very cold conditions.

 

Tired of getting frustrating charging rate on fast chargers (18-25 kW) under cold weather conditions, we got together a group of Kona owners to do some reverse engineering to understand when the battery heater activates. First thing to know, the BMS uses the temperature of lowest battery module in its logic to activate the battery heater. We found 3 conditions for the heater to activate:

1. The battery heater will come On if the SOC is less than 33% and battery temp is -5 degC or less. It goes off when battery reaches 5 degC. This seems to be for conditionning the battery for an eventual stop to a fast DC charger. The Winter Mode needs to be active for this to happen.
   
2. It will also be active when charging on 240v depending on battery temp as well. At -15 degC, it will engage around 82% soc. At 0 degC, it will engage around 91%. At 5 degC, activates around 93%. The Winter mode doesn't need to be active for this.
   
3. The battery will be active on fast charger as well. In most conditions, it will heat the battery upto to 15 degC depending of the starting % SOC. The battery will continu heating due to the heat lost during charging.

Good to know on fast chargers:
Battery temp < 1 degC : max power 18 kW
1 degC > Battery temp > 5 degC: max power 25 kW
5 degC > Battery temp > 15 degC : max power 40 kW
15 degC > Battery temp > 25 degC: max power 50 kW (50kW chargers) or 56 kW (>100kW chargers)
Battery temp > 25 degC: max power > 70 kW (>100kW chargers)

With battery temp as low as -20 degC, no heater activation was observed in other situations. It is believe that at much lower battery temp, the heater will activate to protect the battery. Minimum exterior temperature we had so far is about -25 degC.

 

We forgot to test this. On my next DC charge, I am planning to validate this one. From an other forum I saw, a guy said it needs to be On. We assumed it was not required since it works without it on 240V charge.