Charging protocol
- Thread starter jwarner07
- Start date
Help Support My Nissan Leaf Forum:
If you set a charge timer that prevented the car from charging during the time you had it plugged in, that would also prevent the pack from regaining any charge lost to the climate control, so I don't think that there is a way, other than setting the charge timer to start charging the right amount of time from you ending charging. That would first let the climate control run, then replenish most or all of what was lost.
It also depends on your EVSE. I've found to keep up with preheating in teens or colder, you need around 18a @ 240v to just not lose charge. Of course, if warmer and especially if you have a heat pump or for sure pre-cooling in the summer a much smaller EVSE or even 120v might be able to keep up.
Leftie's advise is good and also the only option I see, that or some smart EVSEs also have a timer function.
Leftie's advise is good and also the only option I see, that or some smart EVSEs also have a timer function.
Stanton
Well-known member
A different answer/consideration to the same question: doesn't hurt to "sit" at 100% when's it cold (for pre-heat), but don't do it when it's hot (for pre-cool). Personally, the only pre-conditioning I have ever done is pre-heat.jwarner07 said:
denwood
Well-known member
I can confirm that plugged in to 16 amps @ 240V and it will not gain charge during pre-conditioning (heat). Conversely, I have not seen charge decrease when plugged in at 120V, but preheat is not effective at -20 C using 120 V.
denwood said:
Please clarify that last part. Since all power for preheating comes directly from the traction battery, preheating in frigid temps should be equally effective whether using L-2 or L-1. Using L-1 should result in a substantial net loss of charge, but it should work. Unless they have made a change to this in the Gen II Leaf...
denwood
Well-known member
My understanding is that during preheat, if a car is plugged in, the system only uses what is available with respect to L1 or L2.
At the EV car show I was in, another owner came up and was asking why preheat on his 2018 was so poor at very low temps. He can only plug into L1 at his house, and does not have a garage. I found the same thing when our LEAF was relegated to outdoor parking for a few months last winter where L1 was all that was available. On L2 preheat is great, on L1, not.
I've also noticed that during preheat, the car does not use the heat pump...resistance only.
I'll take another look at Leafspy with the system on to confirm my previous tests. I seem to recall a max of ~1000 watts or so for heat using the OEM EVSE, L1, 12 amps@120V. Using 16 amps@240V, it's in the 3000 watt range. I've only checked this out on our 2018 SL...and 16 amps is as high as I can go. Plugging into one of the free L2 stations (they deliver about 6 kW), preheat again is great, but I have never checked to see what the HVAC system was using with LeafSpy.
900 watts via L1 might be fine if outside temps are mild, but at -25 C, it's not enough to get to cabin temp targets.
At the EV car show I was in, another owner came up and was asking why preheat on his 2018 was so poor at very low temps. He can only plug into L1 at his house, and does not have a garage. I found the same thing when our LEAF was relegated to outdoor parking for a few months last winter where L1 was all that was available. On L2 preheat is great, on L1, not.
I've also noticed that during preheat, the car does not use the heat pump...resistance only.
I'll take another look at Leafspy with the system on to confirm my previous tests. I seem to recall a max of ~1000 watts or so for heat using the OEM EVSE, L1, 12 amps@120V. Using 16 amps@240V, it's in the 3000 watt range. I've only checked this out on our 2018 SL...and 16 amps is as high as I can go. Plugging into one of the free L2 stations (they deliver about 6 kW), preheat again is great, but I have never checked to see what the HVAC system was using with LeafSpy.
900 watts via L1 might be fine if outside temps are mild, but at -25 C, it's not enough to get to cabin temp targets.
I drove a 2013 Leaf SV for 5 years, and parked it a few yards from the Hudson River. I had no trouble with preheating at low temps. I'd set it to preheat for 5 minutes, and arrived to a car at about 45F, with hot air coming from the HVAC vents, and about a 3% drop in charge. I have seen no indication that the Gen I Leafs limit heater draw according to available charge; they instead pull the full amount from the battery, leaving the charging cable, at whichever level, to replace as much of it as it can. I've seen the same thing with my Gen II Leafs, but not often enough to claim that it's a hard and fast rule. It's been a common misconception here that the HVAC system uses the charging cable to provide preheating power, but that just isn't what happens.
denwood
Well-known member
Ambient temp in the shop was 0 C or 32 F. LeafSpy was plugged in to monitor as the car's HVAC fired up on it's own in the three tests. I set the heat set point to 25 C each time to make sure demand was high. The car door was open too, as I wanted the PTC heater at low resistance. The heat pump did not fire up at all.
Climate control was turned on remotely via the iOS app to 25 C. This is with the OEM L1 EVSE connected at 120V, 12 amps (1440 watts) max:
Climate control turned on (25 C target) via the car's built in timer, with "Battery Operation OK" toggled to ON. This is with the OEM L1 EVSE connected at 120V, 12 amps (1440 watts) max:
Climate control was turned on remotely via the iOS app to 25C. This is with an aftermarket EVSE connected at 240V, 16 amps ( 3840 watts) max:
It looks like the ECU is limiting output from the pack to a total of 1440 watts (ideal) that is available from the OEM L1 EVSE when it is connected. 1000 watts to the PTC heater, 100 to the fan, 200-300 for system overhead. In any case, you can see why preheating at 240V will work a lot better at very cold temps. A cold day here is -35 C (-31 F) and 1000 watts is simply not enough to bring the cabin to 20 C if it has been sitting outside for very long.
If an EVSE cable is not connected, and you have the "Battery Operation Ok" toggled on the car's timer, I'd assume it would give you full output for heat.
Climate control was turned on remotely via the iOS app to 25 C. This is with the OEM L1 EVSE connected at 120V, 12 amps (1440 watts) max:
Climate control turned on (25 C target) via the car's built in timer, with "Battery Operation OK" toggled to ON. This is with the OEM L1 EVSE connected at 120V, 12 amps (1440 watts) max:
Climate control was turned on remotely via the iOS app to 25C. This is with an aftermarket EVSE connected at 240V, 16 amps ( 3840 watts) max:
It looks like the ECU is limiting output from the pack to a total of 1440 watts (ideal) that is available from the OEM L1 EVSE when it is connected. 1000 watts to the PTC heater, 100 to the fan, 200-300 for system overhead. In any case, you can see why preheating at 240V will work a lot better at very cold temps. A cold day here is -35 C (-31 F) and 1000 watts is simply not enough to bring the cabin to 20 C if it has been sitting outside for very long.
If an EVSE cable is not connected, and you have the "Battery Operation Ok" toggled on the car's timer, I'd assume it would give you full output for heat.
I'm not familiar with the aftermarket remote access systems. No argument on 240 volts being more effective for that scenario than 120. What I'm saying is that the car should preheat adequately with either L-1 or L-2 connected, and that the EVSE only charges the battery- it doesn't provide any direct power to the HVAC or to any other system. I don't know if it matters if you have the car in D or Eco mode. It's my understanding that the car should use both the PTC and the heat pump to preheat, as long as temps are inside the boundaries of effective heatpump operation.
denwood
Well-known member
I'm not using any aftermarket remote access..just triggering climate control from the app, or using the car's timer to replicate how you would be using climate control to pre-heat.
The car will use the heat pump as soon as I start driving (outside temps -5 C). It does not use it when connected to L1 or L2 during precondition, and temps in the garage are at 0 C. We're talking pre-heat here only.
The EVSE only charges the battery, however it's quite obvious that with L1 connected, the ECU is managing power use so that the the 400 volt pack output does not exceed the input from the EVSE. This makes sure that the charge level you were expecting, is also what you have on hand when you unplug if using L1. With L2, you get more watts going to heater (like 3 X more) and you do have a bit left over to charge the pack as well.
You are limited to 1000 watts max from the heating system when plugged in with the OEM charger at 120V (L1) as you can see from the first two pics I posted. That may be adequate in warmer climates, but if your target cabin temp is 20 C, and the car has been parked overnight at -25 C ambient, the car will not reach the target temp. I had the LEAF outside last year for about 2 months during the coldest part of winter (average -18 C ) and the cabin was never at the set point preconditioning at L1. L2, no problem.
We're talking a 2018 SL here with heat pump..I have zero experience with the 1st gen LEAF.
The car will use the heat pump as soon as I start driving (outside temps -5 C). It does not use it when connected to L1 or L2 during precondition, and temps in the garage are at 0 C. We're talking pre-heat here only.
The EVSE only charges the battery, however it's quite obvious that with L1 connected, the ECU is managing power use so that the the 400 volt pack output does not exceed the input from the EVSE. This makes sure that the charge level you were expecting, is also what you have on hand when you unplug if using L1. With L2, you get more watts going to heater (like 3 X more) and you do have a bit left over to charge the pack as well.
You are limited to 1000 watts max from the heating system when plugged in with the OEM charger at 120V (L1) as you can see from the first two pics I posted. That may be adequate in warmer climates, but if your target cabin temp is 20 C, and the car has been parked overnight at -25 C ambient, the car will not reach the target temp. I had the LEAF outside last year for about 2 months during the coldest part of winter (average -18 C ) and the cabin was never at the set point preconditioning at L1. L2, no problem.
We're talking a 2018 SL here with heat pump..I have zero experience with the 1st gen LEAF.
My Winter experience is mostly with the first gen Leaf, and that doesn't behave as you say - it will happily run a charge deficit while preheating with L-1 or slow L-2. Since I still use L-1 charging, along with my housemate, and since we both drive Gen II Leafs, I'll check out what happens when preheating while charging. It was obvious with the 2013 because I had to charge that car to 100% in Winter just to make my commute, so I was aware of what was happening with the SOC. Now we rarely charge our cars fully, even in Winter, because we are both retired.
Oh, and I skimmed "ios app" and mistook that for one of the aftermarket apps. I'm getting OLD...
LeftieBiker said:
Hello, I'm a Nissan Leaf Gen 1 user, and sorry but you're wrong. The Nissan Leaf Gen 1. also uses the preheat from the charger, not from the battery as it's explained in the Nissan Leaf Owners Manual (page 4-6):
Only for clarification.
Regards.
That's very interesting! I don't even remember where I read that all power came from the battery, but this is the first time I've seen a real world anecdote that contradicts it. What year Leaf is that manual from? My 2013 SV definitely pulled power from the battery even in frigid temps, losing charge in the process. I've read posts from people here with lower power L-2 setups, and the same was true for them. The 'break even' point for not losing SOC while heating while plugged in is said to be 16 amps from the EVSE...
That would appear to mean that using the climate control timer with the car unplugged would result in no A/C at the set time.
My 2015 shows a less miles and additional charge time needed when pre-heating is used after the battery has been fully recharged and then preheated. So not sure I believe it only pulls from the A/C charge cord, at least on the 2015. IIRC it shows 30 min charge time needed after pre heating.
I think that what's written in that (pre-2013?) manual is not entirely correct. It may represent what was going to be the case at a late stage of the pre-production process - something that got changed in the actual production Leaf. (Some people think that the accessory battery was going to be a lithium battery, but that it was switched to a starting battery to save $$$.) I'm not engaging in CYA here - there is a significant discrepancy between that passage in the manual, and how the cars actually behave...
It's from the 2011 Nissan Leaf owners manual, but that applies to my Gen1 2015 Nissan Leaf.
I use my 220V-240V Nissan Leaf Type 1 travel charger, it's similar to this one: https://i.ebayimg.com/images/g/E54AAOSwz59hlHEv/s-l1600.jpg but with european schuko connector to charge my car every day at work. 15 minutes before I'm going to leave the office, I activate remotely the heating function of the application to preheat the car interior to 24º, when I'm next to the car I can see that the third light of the windshield is blinking (even if the battery finished charging hours ago) and the charger has the "Charge" light led in a darker orange color that when it's charging the main battery.
It doesn't matter if I leave there 15 minutes or half an hour preheating, when I disconnect the charger, the heating function shuts down and my battery percent is always 100% so it match with the 2011 manual statement about using the preheat trough the A/C Timer (or also by simply activating it from the smartphone app as I do) to save battery while the car is still connected to the power supply.
I always used this preheat system to save kWh from my main battery when it's cold outside or to refresh the interior on summer...
I don't know how to attach here the manual or if it breaks any forum rule, but if you want I can upload to any free site and post the link.
Regards.
I use my 220V-240V Nissan Leaf Type 1 travel charger, it's similar to this one: https://i.ebayimg.com/images/g/E54AAOSwz59hlHEv/s-l1600.jpg but with european schuko connector to charge my car every day at work. 15 minutes before I'm going to leave the office, I activate remotely the heating function of the application to preheat the car interior to 24º, when I'm next to the car I can see that the third light of the windshield is blinking (even if the battery finished charging hours ago) and the charger has the "Charge" light led in a darker orange color that when it's charging the main battery.
It doesn't matter if I leave there 15 minutes or half an hour preheating, when I disconnect the charger, the heating function shuts down and my battery percent is always 100% so it match with the 2011 manual statement about using the preheat trough the A/C Timer (or also by simply activating it from the smartphone app as I do) to save battery while the car is still connected to the power supply.
I always used this preheat system to save kWh from my main battery when it's cold outside or to refresh the interior on summer...
I don't know how to attach here the manual or if it breaks any forum rule, but if you want I can upload to any free site and post the link.
Regards.
You can post a page of the manual - just not all of it. So you are in Europe? It's possible that this feature is present only in some European Leafs. I have never before seen anyone mention an extra function (darker LED for preheating) like you describe.
Sorry about the darker LED "Power" light but it seems that finally it's the same orange color. I felt it darker because of the lights at my garage, but yesterday I activated it from the application connected outside and it's the same orange tone.LeftieBiker said:
But what I also did to check this, was to connect my Lelink OBDII to the car while charging and I can confirm it's not using the main battery to preheat the passenger compartment. Check this:
This is the car currently being charged without any preheat powered on. As you can see, ween the screenshot was captured, it was charging 1489 W. to the main battery:
https://ibb.co/2qJ6vwS
Then I just activated the preheat from the Nissan Leaf application and you can see how the Hetr powers on and starts using 1500 W for the preheat and initially 192 W from the main battery (that's only an instant):
https://ibb.co/YcTm2gq
As time passes, you can see that the cabin heater continues using power but at the same time the main battery is being charged, you can see the Batt bar being colored to the right of the graph instead of the left (when using W from the main battery) and the SOC percent being increased, but in any of those cases, the A/C component is 0 W. In the last screenshot I press twice the car's power on button (without using the brake pedal) and the preheat shuts down (it still works if I only press the car's power on button once):
https://ibb.co/Th5Ns7X
https://ibb.co/Mgtfxd8
https://ibb.co/d2P5kk8
https://ibb.co/bW2wwZk
https://ibb.co/6XJBjxr
https://ibb.co/zFmWQsy
So yes, this confirms that the preheat function uses the external power supply energy while the car is still connected with the charger. Obviously, with the preheat function the car will charge slower, all of this was using the travel charger that comes with the car, but in a DC quick charge I don't think it's a relevant usage.
Do you think that being a european charger (at 220-240V) makes a difference on this?
I also attach the captured page from the Nissan Leaf owners manual:
https://ibb.co/n0rtSKB
Regards.
