Scheduled Departure - does it warm the battery?

[xdcthedoc]

Preheating doesn’t warm it enough to provide full regen - only partial regen.

I honestly can't see it happening.

If it is frosty outside and I set my departure time the regen bar has dots all the way along the line when i get in. Hardly warmed up at all.

That is with me putting on the climate half an hour before entry as well... makes almost no difference.

 

[xdcthedoc]

My hunch is the Ampera wasn't being so careful with the battery. You can absolutely pile a ton of regen energy back into a cold battery but it dramatically shortens its life. Be thankful that having to use some friction in the cold is saving your battery for the longer term.

I dont think so - the Ampera battery has had no noticeable degredation in 4 years ownership. They aren't like the early Leafs!

Thinking about it now... when it is cold the petrol engine kicks in early on - it probably heats the battery using that to optimise driving in cold conditions?

 

[Adopado]

I honestly can't see it happening.

If it is frosty outside and I set my departure time the regen bar has dots all the way along the line when i get in. Hardly warmed up at all.

That is with me putting on the climate half an hour before entry as well... makes almost no difference.

I would have thought that the full "thaw" boost on HI from the app should show some noticeable benefit to regen ... anybody?

 

[Jffurlan]

My SR+ gets no noticeable regen boost from running climate on “Hi” before leaving. Most I’ve ever done is 20-30 minutes, although when the car only takes three minutes to get warm that’s all I’ll typically do.

 

[Big Earl]

I would have thought that the full "thaw" boost on HI from the app should show some noticeable benefit to regen ... anybody?

HVAC temperature setpoint has no affect on battery temperature. They're separate systems.

 

[vitesse]

HVAC temperature setpoint has no affect on battery temperature. They're separate systems.

Maybe, but when you heat the cabin before departure and it's cold enough, Teslafi reports that battery heating has triggered. This won't happen if the car is asleep. This may not apply to m3s as they don't have a dedicated battery heater as I understand it.

 

[Big Earl]

Maybe, but when you heat the cabin before departure and it's cold enough, Teslafi reports that battery heating has triggered. This won't happen if the car is asleep. This may not apply to m3s as they don't have a dedicated battery heater as I understand it.

That’s correct - remotely activating the HVAC will also enable battery heating on the S, X and 3 (via the motor(s) on the 3). However, cabin temperature set point, whether 20°C or HI, does not change how much the battery is heated.

 

[Lx2m3]

Does it only warm the battery when climate is set to high?
Is there an indication in TeslaFi that the battery has been warmed?
Apart from increased? regen, are there any benefits from warming the battery?
Is the loss of range worth it (when not plugged in)?

 

[vitesse]

Does it only warm the battery when climate is set to high?
Is there an indication in TeslaFi that the battery has been warmed?
Apart from increased? regen, are there any benefits from warming the battery?
Is the loss of range worth it (when not plugged in)?

Teslafi does show when battery heating has taken place (on our Model S) but I have noticed it only seems to happen when the outside temperature is no higher than 1-2C. It doesn't happen at 3C or higher. The car needs to be awake. I am now routinely pre-heating the car for my wife before she drives to work, though 15 minutes is enough to warm the seats and the cabin, I'm not sure that's enough time to make any difference to the battery if battery heater does come on. Charging the battery before you leave will also warm the battery. But I see most people say that when the temperature is close to freezing, no matter how much pre-conditioning you do there is still some regen limitation once you drive. My wife's commute takes about 50 minutes and is 15 miles. I don't think pre-heating the battery, say, saves money, but it may be good for the long term health of the battery?

 

[Big Earl]

Does it only warm the battery when climate is set to high?
Is there an indication in TeslaFi that the battery has been warmed?
Apart from increased? regen, are there any benefits from warming the battery?
Is the loss of range worth it (when not plugged in)?

No, yes, no, no.

 

[NorfolkMustard]

I don't see battery heating mentioned in teslaFi for my M3. The api has a field for it but I've never seen it active even when "preconditioning for supercharging"

pre-heating the battery could be beneficial for it I suppose - as it's heating it indirectly by heating the coolant around it, rather than heating it by flowing energy through the batteries directly.

 

[Big Earl]

I don't see battery heating mentioned in teslaFi for my M3. The api has a field for it but I've never seen it active even when "preconditioning for supercharging"

pre-heating the battery could be beneficial for it I suppose - as it's heating it indirectly by heating the coolant around it, rather than heating it by flowing energy through the batteries directly.

Some of the fields might not work in TeslaFi, especially in the Model 3. I seem to recall a previous battery heating discussion where this was mentioned.

 

[vitesse]

Some of the fields might not work in TeslaFi, especially in the Model 3. I seem to recall a previous battery heating discussion where this was mentioned.

This would be understandable because the M3 doesn't do battery heating in the same way, so there isn't a dedicated battery heater. Maybe there is a different Tesla API code for the M3?

 

[NorfolkMustard]

as far as I can tell, the api is one-size-fits-all, fields for incompatible hardware are just marked as false/null - e.g.

"has_air_suspension": false,
"has_ludicrous_mode": false,
"sun_roof_installed": null,
"third_row_seats": "<invalid>",

This is the field TeslaFi uses for battery heater monitoring on S/X
'charge_state' -> "battery_heater_on": false,

Worth mentioning
'climate_state' -> "battery_heater": false,
'climate_state' -> "battery_heater_no_power": null,
'climate_state' -> "is_preconditioning": false,
'climate_state' -> "defrost_mode": 0,

and for scheduling
"not_enough_power_to_heat": null,
"scheduled_departure_time": 1574411400,
"scheduled_charging_pending": false,
"user_charge_enable_request": null,
"managed_charging_start_time": null,
"charge_port_cold_weather_mode": false,
"scheduled_charging_start_time": null,
"managed_charging_user_canceled": false

 

[WannabeOwner]

OBD-II port and SCAN software (the one Bjorn is using is Android only I think, but for it to be his first choice its probably the one best suited to Tesla monitoring) would be more likely to give good data about Stators being used for battery heating and, indeed, the temperature of the coolant flowing into / leaving the battery

 

[pdk42]

OBD-II port and SCAN software (the one Bjorn is using is Android only I think, but for it to be his first choice its probably the one best suited to Tesla monitoring) would be more likely to give good data about Stators being used for battery heating and, indeed, the temperature of the coolant flowing into / leaving the battery

Yes, that would prove it pretty convincingly one way or the other. Anyone got the OBD cable and app?

 

[Rob R]

I always assumed that this is what Formula 1 cars have used for a number of years ... anyone confirm or deny?

Pretty sure you are right about F1. I agree that super/ultracapacitors between the batteries and the motors should both give the batteries an easier life, and allow the motors to produce better extremes of performance. I think that in the future the idea of having batteries directly connected to car motors will be seen as a very poor approach. Bear in mind that ex-car batteries can double their life in fixed storage systems after their life in the car is over, because their life is so much easier in a non-car environment. Cars are incredibly demanding on batteries. Supercapacitors are the ideal answer to that. They discharge super fast, for the 0-60 traffic light sprint, then recharge steadily from the battery in normal driving, in preparation for the next piece of driver over enthusiasm.
Tesla/Maxwell are likely to be the first to implement this, I believe.

 

[mpandrew]

Supercapacitors are the ideal answer to that. They discharge super fast, for the 0-60 traffic light sprint, then recharge steadily from the battery in normal driving, in preparation for the next piece of driver over enthusiasm.
Tesla/Maxwell are likely to be the first to implement this, I believe.

The manufacturers are playing with mixing cell types in the same vehicle. Cells are commonly two flavours, energy and power. Energy has more capacity but at the cost of slower charge/discharge rates - think laptops/mobile devices etc. Power have less capacity but are able to charge/discharge faster - power tools/vacuum cleaners, that kind of thing. So the idea is the main pack is primarily energy cells with a smaller buffer of power cells. Power cell part does the hard acceleration and regen then trickles power back/forward to the main energy pack as needed in readiness for the next high power event.

Supercaps are great but still too big/expensive to be practical - that will probably change.

 

[mpandrew]

I dont think so - the Ampera battery has had no noticeable degredation in 4 years ownership. They aren't like the early Leafs!

Thinking about it now... when it is cold the petrol engine kicks in early on - it probably heats the battery using that to optimise driving in cold conditions?

I've read the Ampera has 16kWh pack with only 10.4kWh available to the driver. This is great for pack life as you're not charging the cells to a high voltage, it will explain good life. Also the electronics will change the charging parameters as the pack ages, i.e. as capacity reduces it will charge to a higher voltage so maintain the 10.4kWh for longer.

The other thing I wonder is whether the systems are adding in some friction braking without the driver knowing it, the Tesla doesn't seem to do this unless it's in autopilot mode. I think I read that Leaf models do this?

 

[evM3Sekar]

In the Cincinnati area we have flat electricity rates. In spite of that "Scheduled Departure @ 830a" finishes charging around 600a every time. Doesn't seem to warm the battery.
By choosing "Start Charging at 100a" for an approximate 7.5h charging session with 120V to reach my limit, if I left around 830a, my range and regen are better even in cold mornings (around 32F) compared to having a warm cabin but an already charged battery.