Range reduction

[KiwiME]

As best as I've seen there is no Heater Temp 2, keeping in mind the PID collection is a minimally refined-offshoot of the Kia Soul original. No need to include that PID. Mine has always read zero.

The SoC loss and the difference between displayed and BMS is certainly a new observation for the Kona.

A possibility for the loss (based on my understanding of the workings) is that the tracking of SoC while charging is done only by coulomb counting, quantifying energy added to the pack (essentially the increase in CEC). After charging completes the BMS has an opportunity to access the pack's open-circuit voltage, which when settled is more indicative of the actual SoC. I have no ideas as to how to explain the difference between displayed and BMS values. Using TP logging might lead to more insight.

A few years back I worked on a design team for wild animal tracking collars. All were powered by lithium-metal primary cells and some models also had lithium-ion secondary cells with PV charging. All had supercaps to supplement the high peak current draw from the satellite modem when transmitting. We tested these collars only down to -20°C where performance was poor at best. Where were many of our customers? Canada of course...

 

[apu]

As best as I've seen there is no Heater Temp 2, keeping in mind the PID collection is a minimally refined-offshoot of the Kia Soul original. No need to include that PID. Mine has always read zero.

The SoC loss and the difference between displayed and BMS is certainly a new observation for the Kona.

A possibility for the loss (based on my understanding of the workings) is that the tracking of SoC while charging is done only by coulomb counting, quantifying energy added to the pack (essentially the increase in CEC). After charging completes the BMS has an opportunity to access the pack's open-circuit voltage, which when settled is more indicative of the actual SoC. I have no ideas as to how to explain the difference between displayed and BMS values. Using TP logging might lead to more insight.

A few years back I worked on a design team for wild animal tracking collars. All were powered by lithium-metal primary cells and some models also had lithium-ion secondary cells with PV charging. All had supercaps to supplement the high peak current draw from the satellite modem when transmitting. We tested these collars only down to -20°C where performance was poor at best. Where were many of our customers? Canada of course...

It was interesting as the BMS decided you can not charge the last 20% of you battery's capacity when the pack temperature is -20C. On my 90 minute drive home last night in -28C and with a starting BMS of 80% and 100% indicated I noticed quite a bit of voltage sag particularly on the last 25% SOC. I was also noticing quite large cell difference variations especially when the overall SOC dropped, bad enough that at 12% SOC the turtle light came on and it limited my speed to 90km/hr. At that point the pack had warmed up to 4C. I had tried to hit a nearby petrocan DC charger a little earlier, but neither of the 2 chargers would initiate. By turning off the HVAC I was able mitigate the turtle mode and nurse the car home. Plugged her into the 240V EVSE and this morning its sitting 94% BMS with indicated 100% SOC, total pack voltage 407.6 so almost back to normal. It was -34C overnight and the pack temperature was 1C this morning plugged into the level 2 EVSE . Take away from this is that if its that cold don't rely on a granny charger.

 

[R P]

It was interesting as the BMS decided you can not charge the last 20% of you battery's capacity when the pack temperature is -20C. On my 90 minute drive home last night in -28C and with a starting BMS of 80% and 100% indicated I noticed quite a bit of voltage sag particularly on the last 25% SOC. I was also noticing quite large cell difference variations especially when the overall SOC dropped, bad enough that at 12% SOC the turtle light came on and it limited my speed to 90km/hr. At that point the pack had warmed up to 4C. I had tried to hit a nearby petrocan DC charger a little earlier, but neither of the 2 chargers would initiate. By turning off the HVAC I was able mitigate the turtle mode and nurse the car home. Plugged her into the 240V EVSE and this morning its sitting 94% BMS with indicated 100% SOC, total pack voltage 407.6 so almost back to normal. It was -34C overnight and the pack temperature was 1C this morning plugged into the level 2 EVSE . Take away from this is that if its that cold don't rely on a granny charger.

Wow! Its going to be interesting in the summer if your battery (range) returns to its full capacity. Or if this winter accelerated any long term degradation.

I still say for extreme winter conditions, they need an Extreme Winter mode, that does a better job of keeping the traction battery warm.

 

[apu]

Wow! Its going to be interesting in the summer if your battery (range) returns to its full capacity. Or if this winter accelerated any long term degradation.

I don't think so as it was similarly cold last winter and the capacity test I did a couple of months ago indicated I still had I had full the full 64 kw available to me. The main issue would be force feeding the car with a charge when the pack is really cold. To that end I don't think the BMS will really let you. In the end the extreme cold is hard on everything. Two of the ICE vehicles in the family fleet were put out of commission this morning My wife's newish CRV was down with a dead 12v battery and my son's newish Civic dash lit up like a Christmas tree and went into limp mode when he tried to start it this morning. His 12 V battery had enough amps to turn over his engine but the voltage was low enough confuse the heck out of his car's control modules and set several codes. A quick charge and and disconnected battery ground lead had him in business shortly after. I now have to find time to go to Costco today and buy some new 12 V batteries. Its funny because its a rare moment that the Kona has been more reliable than the gassers.

 

[R P]

Just charged today to 100%, 2nd time ever (I'm on a roll). We just had our coldest week of this winter, with several days below freezing. Yet my GOM today after the charge still showed 444 kms (after turning Climate off). And like the last time, charge tapered down quickly during the last 1/2 hour. But there was no pause at 80 or 90% like others have reported. Didn't get that the last 100% charge either. And I have had all recall and software updates done on my car.