Can't preheat without depleting battery.

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gschettl

Active member
Joined
Jun 6, 2012
Messages
35
Location
jordan minnesota 55352 (Minneapolis suburb)
Is there a way to pre-heat the Leaf cabin without draining the lithium battery? Even when I'm plugged in to a level 2 charger, the timer climate control depletes a full SOC bar from 80% while parked regardless which priority is chosen. I've confirmed that electricity is actually flowing to the car with an ammeter and it is drawing between 10 and 13 amps on both legs, yet it still depletes the battery. I bought this car assuming I could pre-heat it during Minnesota winters without depleting the battery but no luck so far. Gary
 
You might not be losing as much as you think.

Charging to 80% with a new battery pack usually displays
10 bars, because the 10th Bar is just over half full.

If the same bar is just under half full, it will not be displayed,
showing you 9 bars instead of 10. That looks like a whole bar
"less full", but it might be only down one tenth of a bar.

Charging at 16 amp L2 (240v) supplies about 3.3 kW to the battery,
but the heater can draw around 5 kW when on full blast, like it
might be on a cold morning, trying to heat the car to 77 degrees F.
During this time, the battery pack will be discharging somewhat.

Later is the charging cycle, when the cabin (windows up, set to
recirculate air, not use the very cold external "fresh" air) is
warm, the heater should drop to under 2 kW, and the battery
should be able to charge back up to the expected 80%.

If the battery pack is not full enough for your needs, simply
charge to 100% instead of 80%.
 
gschettl said:
Is there a way to pre-heat the Leaf cabin without draining the lithium battery? Even when I'm plugged in to a level 2 charger, the timer climate control depletes a full SOC bar from 80% while parked regardless which priority is chosen. I've confirmed that electricity is actually flowing to the car with an ammeter and it is drawing between 10 and 13 amps on both legs, yet it still depletes the battery. I bought this car assuming I could pre-heat it during Minnesota winters without depleting the battery but no luck so far. Gary
Was the car parked outdoors when you did this ?
What was the temp at that time ?
 
gschettl said:
Is there a way to pre-heat the Leaf cabin without draining the lithium battery? Even when I'm plugged in to a level 2 charger, the timer climate control depletes a full SOC bar from 80% while parked regardless which priority is chosen. I've confirmed that electricity is actually flowing to the car with an ammeter and it is drawing between 10 and 13 amps on both legs, yet it still depletes the battery. I bought this car assuming I could pre-heat it during Minnesota winters without depleting the battery but no luck so far. Gary


What level 2 EVSE are you using?
 
In summary, start pre-heat sooner. As I recall, when plugged in, you can pre-heat for two hours.

I well realize that MN is much colder than here, but today I activated CC 30 minutes before departure and gained charge over the normal 80%.
 
I've had no problems preheating while plugged in. I've really gotten in the habit of hitting my carwings app when I'm approaching checkout lanes so that I get into a warmed car with a heated steering wheel too. LOVE IT! :D

Philip
 
Not being in a frigid climate I have no idea what level of heat can be sustained by "shore power" at low temperatures. 77F may be pretty ambitious for a car that's been cold-soaked at 0F. And the car could use considerable battery before it finally did warm up to the point where L2 provides a "surplus" over and above the heating requirement. If it even could?


This is an area where a few data points might be useful in the Wiki.
 
These replies have already been helpful. A bit more info. The Leaf is parked in my garage which has been around 25°F - 37°F each night during this study. I'm showing 4 bars of battery temperature consistently every day. My Blink charger reports that it is supplying or drawing, (I don't know which) 3.74 kW/hour during charging when the climate control is not on. When I measure amperage it is prior to the Blink charger at a dedicated electric meter using an inductive ammeter. Both the white and black wires are showing 10 or 13 amps each depending what day I check it or possibly heating versus charging respectively. I'm not clear on the math... Would the highest draw be (13amps black wire + 13 amps white wire)x 120 volt each wire= 3.12 kw? [I assume the lower than 3.3 kW reading is a low power factor or non-calibrated ammeter]. I'm losing roughly 2.5 miles of range due to my pre-heat.

Is there a way to safely charge the Leaf at 6.6 kw with my Blink charger?
 
gschettl said:
These replies have already been helpful. A bit more info. The Leaf is parked in my garage which has been around 25°F - 37°F each night during this study. I'm showing 4 bars of battery temperature consistently every day. My Blink charger reports that it is supplying or drawing, (I don't know which) 3.74 kW/hour during charging when the climate control is not on. When I measure amperage it is prior to the Blink charger at a dedicated electric meter using an inductive ammeter. Both the white and black wires are showing 10 or 13 amps each depending what day I check it or possibly heating versus charging respectively. I'm not clear on the math... Would the highest draw be (13amps black wire + 13 amps white wire)x 120 volt each wire= 3.12 kw? [I assume the lower than 3.3 kW reading is a low power factor or non-calibrated ammeter]. I'm losing roughly 2.5 miles of range due to my pre-heat.

Is there a way to safely charge the Leaf at 6.6 kw with my Blink charger?
Well, nit pic. The answer is the same, but it is not 120 Volts(13 Amps + 13 Amps) = 26 Amps X 120 volts. It is 13 Amps X 240 volts. It is the same current flowing through both wires.

No, you can not charge at 6.6 kW. The charger is in the car and 3.3 kW is the max no matter how many Amps are available for charger use. Ingineer Phil has come up with an additional installed charger, but has not offered the mod, and sounds like he will not.

Supposedly, a 6.6 kW charger will be offered as an option on the 2013s.
 
OP: it's not clear from your postings, but how long did you have the CC on for in your experiments? Like others here, I have no experience with your kind of cold but, hopefully, if you pre-heat long enough, your heat draw will stabilize at less than what is supplied to the charger and you can start gaining back charge. Here in California in mid-40F temperatures, if I pre-heat for 1 hour, starting with 10 bars (80%), I end up at 11 bars of charge.

I would try your experiment again, but try for at least 1 hour. If this does not return you to at least 10 bars, it may just be too cold.
 
Why would anyone preheat for an hours time. The car can warm up just fine in 5 minutes.
 
as said don't be afraid to prewarm for a good long while from an 80% charge... eventually it will actually charge the battery some once the core of the car warms up enough for the thermostat to go off intermittently.

To preserve the heat the most, change the mode to "foot/defog" set auto to the temp you like and then hit the on/off button to set the CC to Off for the first leg of the drive, this will retain the heat. the foot/defog setting allows some passive defogging while having the temp set already will make it easy to simply hitt the on/off button to turn the CC on without requiring further adjustment once underway. simply toggling the on/off button based on comfort vs required range is easier than constantly changing the set temp.
 
KJD said:
Why would anyone preheat for an hours time. The car can warm up just fine in 5 minutes.

Heh, not if it's cold outside. I need at least 15 minutes to clear ice from the windshield, sometimes upwards of 30 minutes to clear all windows.
 
KJD said:
Why would anyone preheat for an hours time. The car can warm up just fine in 5 minutes.
Maybe in SLC, but not in Puyallup, and I'm certain not during deep winter in Minnesota. I've been there in January, and it ain't nice.
 
15 minutes of preheat inside a 20 degree garage has my Leaf toasty warm. The warmth lasts about 10 miles before my feet get cold. I do not see a need to preheat any longer than that. Also, I, too notice that a 80% charge with preheated Leaf does indicate 9 bars when I depart each morning.
 
Rauv said:
15 minutes of preheat inside a 20 degree garage has my Leaf toasty warm. The warmth lasts about 10 miles before my feet get cold. I do not see a need to preheat any longer than that. Also, I, too notice that a 80% charge with preheated Leaf does indicate 9 bars when I depart each morning.
The request of the OP was to pre-heat and not lose any bars after 80% charging. That's why I suggested pre-heating for an hour. Try to get the heater's draw down enough for a long enough time to regain any lost charge in the initial pre-heating. It may not require an hour, but that's a good starting point.

The other approach, especially in winter with low temperatures, is to just charge to 100%, hopefully finishing not too long before driving. This way, even after a shorter pre-heat, you'd still be over 80%. AFAIK, at these low temperatures, leaving the battery at 100% for a few hours is unlikely to any damage.
 
For these experiments I'm using the CLIMATE CONTROL departure timer to pre-heat the car automatically each morning and I set it to expire before I actually unplug and drive. It typically runs heat for about 30 minutes prior to the departure time and I lose one bar, (or a portion of a bar in theory, or ~2.5 miles range) during the preheat. I tried some timer trickery by using a departure CHARGE timer set to later than the CC departure timer but to my surprise this charging timer finishes the charge hours prior to my departure rather than minutes prior. Also it seems that the charger won't trigger on twice, once prior to heating, & once after. Minnesota Gary
 
gschettl said:
For these experiments I'm using the CLIMATE CONTROL departure timer to pre-heat the car automatically each morning and I set it to expire before I actually unplug and drive. It typically runs heat for about 30 minutes prior to the departure time and I lose one bar, (or a portion of a bar in theory, or ~2.5 miles range) during the preheat. I tried some timer trickery by using a departure CHARGE timer set to later than the CC departure timer but to my surprise this charging timer finishes the charge hours prior to my departure rather than minutes prior. Also it seems that the charger won't trigger on twice, once prior to heating, & once after. Minnesota Gary
Try, instead of using the timer, remotely starting CC through CarWings (web, smartphone app, etc.). This way, it will run for up to 2 hours (if plugged in).
 
DoxyLover said:
gschettl said:
For these experiments I'm using the CLIMATE CONTROL departure timer to pre-heat the car automatically each morning and I set it to expire before I actually unplug and drive. It typically runs heat for about 30 minutes prior to the departure time and I lose one bar, (or a portion of a bar in theory, or ~2.5 miles range) during the preheat. I tried some timer trickery by using a departure CHARGE timer set to later than the CC departure timer but to my surprise this charging timer finishes the charge hours prior to my departure rather than minutes prior. Also it seems that the charger won't trigger on twice, once prior to heating, & once after. Minnesota Gary
Try, instead of using the timer, remotely starting CC through CarWings (web, smartphone app, etc.). This way, it will run for up to 2 hours (if plugged in).
Or try the method reserved for those who do not have access to web or smartphone:
http://www.mynissanleaf.com/viewtopic.php?f=31&t=11006&p=253593#p253593
This method does not pull electrons from the battery, only the wall.
Reddy
 
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