Smart preconditioning vs. phone app

[theslimshadyist]

So, to create more confusion is the census that if you are plugged in with range mode off and enable the cabin heat via the app, the batteries will in fact warm up?

Sheesh, this is clear as mud!

 

[Andyw2100]

So, to create more confusion is the census that if you are plugged in with range mode off and enable the cabin heat via the app, the batteries will in fact warm up?

Yes, but not much.

 

[WannabeOwner]

Yes, but not much.

That's my consensus too. I have not found anything that guarantees that the battery is warm when I leave, except prolonged charging overnight, and the car still charging when I leave. And that's in the UK where typically when I leave (this time of the year) the Winter temperature is only 0C to 8C - so not cold by cold-country standards!

I'm sure there is an amount of battery charging that will do, but I've been raising the charge limit to force charging for an extra 30 - 60 minutes before leaving and putting the cabin on MAX and I still often have regen limited when I leave and car.

Sheesh, this is clear as mud!

Snap! Wifee tells me that I am a "detail person" but my scenario would make for a very complicated "preconditioning" solution. The Command would be simple, the Effect would be complex, but I think it would be do-able.

For me part of the problem is scheduled charging [if I plug in]. We have Off Peak (cheaper) electricity 24:00 to 07:00, so I have the car set to start charging at 00:05. What I really want is for something to start the charging at 00:05, but to then also charge for X hours before I leave - i.e. stop the overnight charge short, if necessary, and resume it later. One option would be to delay the start of charging so that it reaches 90% just as I leave, but a power-cut would scupper that, so I'd prefer to charge to 80% Off Peak and then again from 80% to 90% an hour before I leave (assuming 10% charging takes one hour). Worst case, if there was a power cut, I'd leave with 80%.

The APPs that seem to have an ability to do this aren't keen on stopping charging at all - because once they stop if they can't then re-start its a support / "liability" issue. Understood.

So my thought is to use Amazon Echo, or similar, to achieve this. "Alexa, charge the car to 90% and prepare for departure at 07:00"

I envisage this overriding Tesla scheduled charging (not sure how to achieve that, maybe it has to be allowed to start and then be stopped immediately ...) to do the majority of charging as soon as Off peak starts, and then if the departure time will be cold to do the last 10% an hour before leaving.

"Departure at nn:nn" would check what the forecast temperature will be and, if cold, schedule final part of charging just before then and if Hot just turn on Climate (AirCon) for some minutes before then. Additionally if there is not enough time between 00:00 and my (early morning) departure time to sufficiently charge the car it can start charging before the Off Peak rate.

"Charge the car to nn%" could cover various scenarios. Of course "100%" and "90%" (or whatever the user normally does). It also needs to cover my situation which is that I also charge at work and my preference is to charge only at work, unless I have a trip to make starting from home. So basically I want to plug in at home, always, but never to actually charge unless necessary. "Necessary" would include warming the battery enough for full regen, etc. or if going on a long trip.

 

[JHuberman]

I don't think any of the above is accurate information.

You can have your charge limit set to anything you want, and as long as the battery has room to accept more power, if regen is available (battery not too cold) regen will work. Setting the charge limit to 100% after disconnecting would accomplish absolutely nothing.

Also, if regen is not available because the battery is cold, nothing you wrote above will change that.

Charging a good amount just before leaving will warm the pack, but very possibly not enough to eliminate the restriction on regen. It depends on the temperature and how much heat is generated during charging.

Warming the cabin, with range mode off, will also heat the pack some, but not very much.

Just wondering, @JHuberman, what the source of your information was.

Experience - My information comes from having no regen and seeing the yellow line indicating such. Changing the battery charge limit and immediately having regen capability - all within the first minute of starting out. I have a new MS60. Temperature was in the 40'sF. Charging had stopped hours earlier. I hope this helps clarify things.

 

[Andyw2100]

Experience - My information comes from having no regen and seeing the yellow line indicating such. Changing the battery charge limit and immediately having regen capability - all within the first minute of starting out. I have a new MS60. Temperature was in the 40'sF. Charging had stopped hours earlier. I hope this helps clarify things.

I don't know if the fact that you have a 60 that is really a 75 could be factoring in, but what you describe is unique. It is not the experience of others here on TMC. Not even close.

 

[NullException]

For me part of the problem is scheduled charging [if I plug in]. We have Off Peak (cheaper) electricity 24:00 to 07:00, so I have the car set to start charging at 00:05. What I really want is for something to start the charging at 00:05, but to then also charge for X hours before I leave - i.e. stop the overnight charge short, if necessary, and resume it later.

VisibleTesla allows you to do exactly this, I believe. You need your own local kit to run it. I'm pretty sure it's no longer in active development, though.

 

[JHuberman]

I don't know if the fact that you have a 60 that is really a 75 could be factoring in, but what you describe is unique. It is not the experience of others here on TMC. Not even close.

I am traveling now, but when I return home and lower the charge limit I will test this again and report back. Maybe there was a confounding factor I was not aware of. Since others have a different experience, I will be careful to record times and temperature.

 

[Andyw2100]

I am traveling now, but when I return home and lower the charge limit I will test this again and report back. Maybe there was a confounding factor I was not aware of. Since others have a different experience, I will be careful to record times and temperature.

Awesome! Sounds like a good plan. Thanks!

 

[_jal_]

So, to create more confusion is the census that if you are plugged in with range mode off and enable the cabin heat via the app, the batteries will in fact warm up?

Sheesh, this is clear as mud!

I'm in Chicago and we've had a couple weeks of cold weather. -5 to 10 in the morning. I go to the gym at 6. I wake up at 5:30, walk in circles for 10 minutes or so, then start to make my way to the car. I am usually in by 6:00. I preheat via the app when I attain consciousness at about 5:40 meaning I usually get about 20 min of preheating. My battery is always charged by 9 or 10 at night. When I turn on the climate, my cabin temperature is usually in the 20's when it is near zero outside (It's in a detached garage). I tend to get somewhere in the 30kW limit for regen.

I fiddled with Range Mode a little bit and a couple of times I've accidentally left it on overnight. The result is that with the same routine, I get in and have 0 regen. Absolutely 0.

To further complicate things, I have used scheduled charging a couple of times to see if I could increase the regen output by finishing charging at or close to 5:30, and it did not increase it more than the warming did.

So that's my experience. Warming with range mode off gives you some regen (about 30kW). Warming with range mode on give you no regen.

 

[xsi123]

How would you test unless you have some software or something that will tell you the temperature of the pack? It seems the regen limit when cold has definitely become more aggressive, so when it's cold I seem to be regen limited unless I have just charged, and even then sometimes. What I'm saying is that I can't use the regen limit to determine whether or not the pack was heating when the cabin was or not.

Interested in hearing how you plan to test.

Thanks!

Using the API should be simple to figure out when the battery heater is on or off. The charge_state call gives you back a "battery_heater_on" status.

{
"response": {
"charging_state": "Disconnected",
"charge_limit_soc": 90,
"charge_limit_soc_std": 90,
"charge_limit_soc_min": 50,
"charge_limit_soc_max": 100,
"charge_to_max_range": false,
"battery_heater_on": null,
"not_enough_power_to_heat": false,
"max_range_charge_counter": 0,
"fast_charger_present": false,
"fast_charger_type": "<invalid>",
"battery_range": 221.78,
"est_battery_range": 170.06,
"ideal_battery_range": 276.99,
"battery_level": 88,
"usable_battery_level": 88,
"battery_current": -0.1,
"charge_energy_added": 0,
"charge_miles_added_rated": 0,
"charge_miles_added_ideal": 0,
"charger_voltage": 0,
"charger_pilot_current": 48,
"charger_actual_current": 0,
"charger_power": 0,
"time_to_full_charge": 0,
"trip_charging": false,
"charge_rate": 0,
"charge_port_door_open": false,
"scheduled_charging_start_time": null,
"scheduled_charging_pending": false,
"user_charge_enable_request": null,
"charge_enable_request": true,
"charger_phases": null,
"charge_port_latch": "Engaged",
"charge_current_request": 48,
"charge_current_request_max": 48,
"charge_port_led_color": "Off",
"managed_charging_active": false,
"managed_charging_user_canceled": false,
"managed_charging_start_time": null,
"motorized_charge_port": true,
"eu_vehicle": false,
"timestamp": 1484325557871
}
}

 

[Andyw2100]

Using the API should be simple to figure out when the battery heater is on or off. The charge_state call gives you back a "battery_heater_on" status.

{
"response": {
"charging_state": "Disconnected",
"charge_limit_soc": 90,
"charge_limit_soc_std": 90,
"charge_limit_soc_min": 50,
"charge_limit_soc_max": 100,
"charge_to_max_range": false,
"battery_heater_on": null,
"not_enough_power_to_heat": false,
"max_range_charge_counter": 0,
"fast_charger_present": false,
"fast_charger_type": "<invalid>",
"battery_range": 221.78,
"est_battery_range": 170.06,
"ideal_battery_range": 276.99,
"battery_level": 88,
"usable_battery_level": 88,
"battery_current": -0.1,
"charge_energy_added": 0,
"charge_miles_added_rated": 0,
"charge_miles_added_ideal": 0,
"charger_voltage": 0,
"charger_pilot_current": 48,
"charger_actual_current": 0,
"charger_power": 0,
"time_to_full_charge": 0,
"trip_charging": false,
"charge_rate": 0,
"charge_port_door_open": false,
"scheduled_charging_start_time": null,
"scheduled_charging_pending": false,
"user_charge_enable_request": null,
"charge_enable_request": true,
"charger_phases": null,
"charge_port_latch": "Engaged",
"charge_current_request": 48,
"charge_current_request_max": 48,
"charge_port_led_color": "Off",
"managed_charging_active": false,
"managed_charging_user_canceled": false,
"managed_charging_start_time": null,
"motorized_charge_port": true,
"eu_vehicle": false,
"timestamp": 1484325557871
}
}

So as I suggested in the post of mine that you quoted, you do have software to assess the status / temperature of the pack, as you're talking about API stuff.

 

[JHuberman]

I don't think any of the above is accurate information.

You can have your charge limit set to anything you want, and as long as the battery has room to accept more power, if regen is available (battery not too cold) regen will work. Setting the charge limit to 100% after disconnecting would accomplish absolutely nothing.

Also, if regen is not available because the battery is cold, nothing you wrote above will change that.

Charging a good amount just before leaving will warm the pack, but very possibly not enough to eliminate the restriction on regen. It depends on the temperature and how much heat is generated during charging.

Warming the cabin, with range mode off, will also heat the pack some, but not very much.

Just wondering, @JHuberman, what the source of your information was.

I've been watching this issue when I start driving now, and my previous post about changing battery setting does happen sometimes and not at other times. I have started driving with battery at 100%, temperature at about 50 F, and sometime I have very little regen and the yellow dashes inform me of that, and other times under the same situation there is no regen limit. So I retract my previous advice because I am not getting consistent results to what appears similar conditions.

 

[Andyw2100]

I've been watching this issue when I start driving now, and my previous post about changing battery setting does happen sometimes and not at other times. I have started driving with battery at 100%, temperature at about 50 F, and sometime I have very little regen and the yellow dashes inform me of that, and other times under the same situation there is no regen limit. So I retract my previous advice because I am not getting consistent results to what appears similar conditions.

I appreciate your retracting your previous advice. But I want to add some information to what you wrote above.

Most people who charge to 100% would not have any regen available when they start their drives. The fact that you do must be because you have a 60 that is software limited to 60, but which is really a 75.

 

[JHuberman]

I appreciate your retracting your previous advice. But I want to add some information to what you wrote above.

Most people who charge to 100% would not have any regen available when they start their drives. The fact that you do must be because you have a 60 that is software limited to 60, but which is really a 75.

That is all well and good for a theory, but sometime I do have limited regen. Even if I haven't charged all the way.
My current theory is that the car is doing things to the battery on its own schedule and sometimes you start up when either the battery is down &/or warmed and you have regen.
I have noticed that even after the car is charged fully and locked which prevents the "charging" or "charged" light from illuminating, from time to time the charge light will show steady green for a minute or so and then go off. Later in the night it will come on and go off again. (I can see the car from our bedroom).
So my working hypothesis is that some battery maintenance is going on, and possibly where you start the car in that cycle may determine whether you have regen or not.

 

[Andyw2100]

That is all well and good for a theory, but sometime I do have limited regen. Even if I haven't charged all the way.
My current theory is that the car is doing things to the battery on its own schedule and sometimes you start up when either the battery is down &/or warmed and you have regen.
I have noticed that even after the car is charged fully and locked which prevents the "charging" or "charged" light from illuminating, from time to time the charge light will show steady green for a minute or so and then go off. Later in the night it will come on and go off again. (I can see the car from our bedroom).
So my working hypothesis is that some battery maintenance is going on, and possibly where you start the car in that cycle may determine whether you have regen or not.

The most likely reason that you sometimes have a regen limit is the battery being below a certain temperature.