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Merged Post With Link to Relevant Documents

Hello members. Cold Weather has hit the Carolinas (below freezing last evening and forecasted for the next couple of nights). On my drive to work this morning, it was a crisp 27 degrees. I know we have members in DC/Atlanta/NY/Chi/Denver/Washington, etc). Therefore, I thought it may help to share with everyone the Cold Weather Charging Consideration (source -Fisker Owner Handbook):

"Do not allow the vehicle to remain in temperature extremes for long periods without being driven or plugged in. When not operating the vehicle it is recommended that the vehicle be plugged in and charging when temperatures are below 32 degrees F (0 degrees C). Note: Keep the vehicle plugged in, even when fully charged, in order to keep the battery temperature prepared for the next drive. This is important when outside temperatures are extremely cold.

Stay warm (both all of you and your awesome Fiskers).
Please feel free to share any other cold weather advice or tips/tricks to keep our vehicles safe and sustainable.

maybe the mods can add this to the first post?

810120054.01 Vehicle Storage Guidelines.pdf 69 KB

https://mega.co.nz/#!2Y4gxZzb!Sf9HVz_bRgTPjXWkJnVFnQhuMOJRHRFQ41fGHAhaedg

890120045.01 Karma Battery Maintenance and Storage Guidelines.pdf 77 KB

https://mega.co.nz/#!LYI1CQBL!LMNeZ1_34djSEcEg2gjwK0anF7wv0UD5rIO-1IFeOIc
 

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If you're going to leave it plugged in for an extended period of time to the charger, get yourself a trickle charger for the 12V Battery as well.
 

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The HV PTC heater is mainly for when the vehicle is being operated on exclusive battery power (ICE is off) and does not turn on when the vehicle is plugged in and the contactor is open. The only negative of storing batteries at cold temperatures is cold soak (which is temporary). Li-Ion batteries are best preserved being stored in cold weather. It is hot weather that is far more damaging to Li-Ion batteries. Here is a great paper on the topic:

http://ma.ecsdl.org/content/MA2011-02/17/1282.full.pdf
 

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My post about the trickle charger was simply to help those owners that would like to follow what the Owner's Manual says. For roughly a $40-$60 investment, it'll save you a lot of headache. Case in point, a client of mine put a trickle charger on his car when he stored it back in May. Now in November he returns to California, takes the car off the trickle charger and it immediately starts right up. Without the trickle charger, I can almost guarantee he'd have come back to a dead car.
 

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Lormax/Harley: if we want to top off our 12 V batteries during the winter by simply turning the Karma on in our garage and letting the HV battery charge the 12 V battery, how long should we let the car idle to ensure the 12 V is fully charged?

Thanks!
 

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but what does the ptc heater have to do with plugging it in?

The HV PTC circulates coolant to keep the battery warm (if necessary) but turns off once the contactor opens up (i.e. full charge). Once this occurs you will not be circulating any warm coolant so it is useless to plug in. The main problem is leaving the battery at a high SOC for a long period of time (caused by plug in since you cannot set SOC thresholds in the Karma). Why not just charge the battery to a 50% SOC and unplug the 12v and be done with it? What is the benefit of leaving the car plugged in and putting a trickle charger on the 12v for months at a time? So you don't lose your radio presets maybe? Long term this could lead to HV battery degradation.
 

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The HV PTC circulates coolant to keep the battery warm (if necessary) but turns off once the contactor opens up (i.e. full charge). Once this occurs you will not be circulating any warm coolant so it is useless to plug in. The main problem is leaving the battery at a high SOC for a long period of time (caused by plug in since you cannot set SOC thresholds in the Karma). Why not just charge the battery to a 50% SOC and unplug the 12v and be done with it? What is the benefit of leaving the car plugged in and putting a trickle charger on the 12v for months at a time? So you don't lose your radio presets maybe? Long term this could lead to HV battery degradation.
There's 3 separate coolant systems on the Karma: Battery, Motor Electronics, and ICE/Cabin Heating. The PTC is located in the ICE/Cabin Heating Loop and does not affect the temperature of the battery coolant system. The A/C is connected to the battery coolant system, maybe thats what you mean.

Contrary to the incorrect owner's manual, Fisker recommends that the vehicle is stored unplugged from the wall charger, with the SOC between ~40-60%, and preferably connected to a 12 volt battery maintainer. Disconnecting the 12 volt battery is okay but like you said, you lose all your preferences etc.
 

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There's 3 separate coolant systems on the Karma: Battery, Motor Electronics, and ICE/Cabin Heating. The PTC is located in the ICE/Cabin Heating Loop and does not affect the temperature of the battery coolant system. The A/C is connected to the battery coolant system, maybe thats what you mean.
There is another loop (at least on my Karma) that goes from the PTC to the HV pack, OBCM, inverters and motors.
 

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There's 3 separate coolant systems on the Karma: Battery, Motor Electronics, and ICE/Cabin Heating. The PTC is located in the ICE/Cabin Heating Loop and does not affect the temperature of the battery coolant system. The A/C is connected to the battery coolant system, maybe thats what you mean.

From the First Responder pdf

It states that there is a separate PTC loop to the ESS (Energy Storage System aka HV Battery).

There is a 3 way valve on the backside of the loop that either heats or cools the battery depending on operational requirements.
 

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From the First Responder pdf

It states that there is a separate PTC loop to the ESS (Energy Storage System aka HV Battery).

There is a 3 way valve on the backside of the loop that either heats or cools the battery depending on operational requirements.
I'm sure that was written by the same people that wrote the owners manual. If you want to believe that then by all means, im not gonna argue.
 

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I had a full response typed up, then my laptop hit the back button probably because I grazed across the mouse pointer area and I lost it. The basics...8AVGMPG is correct, the battery coolant isn't connected to the PTC heater.
 

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Ok so I just tested this again with CANoe

0x0235 Traction Batt Status 1 is closed

0X163 shows a temperature very similar to what my probe is capturing at the Aux Heating Pump (CWA50)

What are your named parts for C13113320100x & C13113420100x? Mine shows it at Pump for Battery Heating & Aux Pump for Battery Heating. These two pumps directly feed the cooling hoses via T with a check valve on the back to the heater in. The PTC definitely is feeding the Aux Heating Pump which is part of the battery thermal management solution.

So perhaps all the documentation and the car itself was designed by the same people who wrote the manual?
 

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Thanks 8AVG-- those documents were very helpful.

One important point I learned in the second document is that when the Karma's HV is plugged in AND CHARGING (but not if plugged in with HV battery at 100%), the 12V will charge as well.
 

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25 to 30% less range in freezing temperatures?

In the words of the Starks, "Winter is Coming." In the spirit of the original post, I am experiencing the first cold temperatures and noticing that I am getting around 20 to 25 percent less range in stealth.

Is that what others are seeing too? Taking the kids to school with a full charge, and back is a great benchmark, because I usually have 32 miles of range, but with the lower temperatures, I got in with 27. Or, driving up to the top of the mountain, I usually have 13 miles of range left, and I only had 3.

Is this what other have experienced as well? (I have a little less than 15k miles on it with a little over 60% of miles on electric).
 

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I can't say 100 percent whether the seat warmers or heater was on - (if heater was on, it was on a fan setting of 1)... But, I will try this morning with all of it off, and check the range.
 
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