Can the on-route-preheat be turned off?

[Magnets!]

Elon knows best....go with it

 

[cizUK]

I would imagine if you are in critical low soc and going to a supercharger, will that pre-heat deplete your battery before arriving the supercharger?

Even harder case, what if you arrived at the supercharger with battery preheated, but only find there is a super long waiting queue? Will the battery keep heated while waiting? That sounds ridiculous.

I would hope there be a toggle for us to choose enable on route preheat or not.

How long this pre-heating takes? Based on the info: Introducing V3 Supercharging

I assume Tesla calculates average Supercharging session to be 30 mins now, with a potential to decrease it by 25% just by pre-heating. This gives around 7.5 minutes to pre-heat, which means Tesla should start doing it around 7-9 minutes BEFORE estimated arrival time.

I think it also matters how much energy it takes to KEEP the battery pre-heated (I assume the battery will remain pre-heated if Supercharger is backlogged until you plug-in).

Let's look at this logically.
If the battery is preheating for around 8 minutes at its heater's capacity of 4.8 kW, you will have used approx 0.64% of your battery, or 2.5 miles of range.
If you can't afford to lose that, you shouldn't be planning for the next supercharger to be a backup.
Seriously, there will be very few issues in very select corner cases - it won't be a problem.

 

[Mark Z]

Preheat is perfect for those with free Supercharging.

How many paying users will complain that the new preheating feature is costing them additional charging fees?

 

[ramonneke]

Pre-heating will be *very* simple to automate.

First of all, it would only be checked if needed when actually navigating to a SuC. It then checks the current battery pack temperature, checks what the temperature will be when arriving at the SuC based on historical data. If battery needs more temperature *and* the SoC allows for it then it would activate it.

Really super easy to implement and nothing to worry about.

If you would use SuC as intended, so as to charge during large trips then the battery would already be heated just by usage.

Only for that percentage of customer that cannot charge at home or don't want to pay for charging and are willing to spend their time (time=money) to travel back/forth a SuC would benefit.

 

[SammichLover]

And I don’t think that’s a professional engineer/product designer should do to “let the customer think of hacky bypass”. It’s what we can think, but not what they can assume.

I don't understand what you're doing to start with that isn't to start with, roughly speaking, "hacky". I don't get your use case. Rather than ranting about how their design is bad can you please explain what you're trying to do here?

 

[SammichLover]

Yes and I would expect they use the navigation arrival time to charging starting time gap to do some statistics and detect whether a supercharger is backlogged. However, they are still using the dumbest logic.

That's often not how it works for looking ahead. Unless the SC is perpetually full. Even 2-3 minutes out from a modestly busy SC I can't say for sure if I'll need to wait, as others could be pulling in ahead.

They could potentially try check their servers for routing requests that have been made (and if they aren't already gather the data, check see if the Nav is still active on it) to that SC but haven't arrived yet. But that's the sort of approach you just dropped a chocolate soft-serve ice cream on.

 

[Subhuman]

I'm still trying to understand the whole heating aspect of the battery. I get that it needs to be at an ideal temperature to charge at the higher charge rate but I can not figure out exactly when that happens.

Numerous times this winter I have been driving for around an hour and a half starting with a cold battery. Over my journey the dots showing regen limited go away. I arrive at the supercharger with full regen capability which I assume means the battery is at it's ideal temperature.

However when I plug it in, the charge rates have been limited to 30-50 kW with one time reaching to 70 kW. I typically have a starting SOC of 30%. I have used this same supercharger in the summer and had no issues achieving 120 kW rate of charge so I know there is no issue with the charging station. Can anyone explain the discrepancy.

I hope that the on route preheat eliminates this issue. Nothing is more annoying than supercharging at a max rate of 30 kW.

 

[SammichLover]

However when I plug it in, the charge rates have been limited to 30-50 kW with one time reaching to 70 kW. I typically have a starting SOC of 30%. I have used this same supercharger in the summer and had no issues achieving 120 kW rate of charge so I know there is no issue with the charging station. Can anyone explain the discrepancy.

The regen brakes do not attempt to push kW100 into your battery. For RWD the max will be around 55kW or so (I don't know the exact number), for AWD it'll be closer to 70kW. That is also usually in a burst, unless you're driving down the side of mountain on a fairly constant grade road, as opposed to the sustained charging of the SC over sever minutes.

The state of the battery being in the gap between those to is what likely accounts for this.

 

[Subhuman]

The regen brakes do not attempt to push kW100 into your battery. For RWD the max will be around 55kW or so (I don't know the exact number), for AWD it'll be closer to 70kW. That is also usually in a burst, unless you're driving down the side of mountain on a fairly constant grade road, as opposed to the sustained charging of the SC over sever minutes.

The state of the battery being in the gap between those to is what likely accounts for this.

Thanks. This makes sense but if the battery pack isn't warmed up after an hour and half of interstate driving @ 75 MPH when would it ever be warm enough. I'm not sure how much influence on-route-preheat will have if and hour and half of driving still does not get the battery to the proper temperature.

 

[SammichLover]

Thanks. This makes sense but if the battery pack isn't warmed up after an hour and half of interstate driving @ 75 MPH when would it ever be warm enough.

The Model 3 has a frighteningly efficient drivetrain. When you rely on the inefficiency to heat the battery, depending on how cold it is outside, it can indeed take longer than that.

 

[SabrToothSqrl]

y'all worry too much. just drive the car.

 

[ItsNotAboutTheMoney]

I would imagine if you are in critical low soc and going to a supercharger, will that pre-heat deplete your battery before arriving the supercharger?

Even harder case, what if you arrived at the supercharger with battery preheated, but only find there is a super long waiting queue? Will the battery keep heated while waiting? That sounds ridiculous.

I would hope there be a toggle for us to choose enable on route preheat or not.

On-Route Battery Warmup
New Supercharging infrastructure isn’t the only way we are improving our customers’ charging experience. Beginning this week, Tesla is rolling out a new feature called On-Route Battery Warmup. Now, whenever you navigate to a Supercharger station, your vehicle will stupidly heat the battery to ensure you fail to arrive but with the battery at the optimal temperature to charge, reducing average charge times for owners by 25% by making sure that you're not there, you EVhole.

I think that's clear.

 

[TheGrimSweeper]

It hasn't even been released yet and you are already complaining? We don't even know what it will look like in the app yet

 

[Daniel in SD]

Thanks. This makes sense but if the battery pack isn't warmed up after an hour and half of interstate driving @ 75 MPH when would it ever be warm enough. I'm not sure how much influence on-route-preheat will have if and hour and half of driving still does not get the battery to the proper temperature.

I'm pretty sure they have the ability to reduce the efficiency of the motor to generate more heat.
If the motor is 95% efficient then driving for an hour and a half would only generate 1.7kWh of waste heat.
1.5h*75mph*300Wh/mi*5%=1.7kWh

 

[CCIE]

I'm still trying to understand the whole heating aspect of the battery. I get that it needs to be at an ideal temperature to charge at the higher charge rate but I can not figure out exactly when that happens.

Numerous times this winter I have been driving for around an hour and a half starting with a cold battery. Over my journey the dots showing regen limited go away. I arrive at the supercharger with full regen capability which I assume means the battery is at it's ideal temperature.

However when I plug it in, the charge rates have been limited to 30-50 kW with one time reaching to 70 kW. I typically have a starting SOC of 30%. I have used this same supercharger in the summer and had no issues achieving 120 kW rate of charge so I know there is no issue with the charging station. Can anyone explain the discrepancy.

I hope that the on route preheat eliminates this issue. Nothing is more annoying than supercharging at a max rate of 30 kW.

Minimum battery temperature to fully regen and optimal battery temperature to supercharge are likely 10s of degrees apart. You may get full regen at 50F, but optimal supercharge is 80F. In winter in many areas the battery will never get to 80F, which is why many of us have been seeing max supercharge rates with "warm" cars around 70kw.

This new feature should, given a decent length drive, bring the battery to optimal supercharge temperature. I can't wait!

 

[Subhuman]

The Model 3 has a frighteningly efficient drivetrain. When you rely on the inefficiency to heat the battery, depending on how cold it is outside, it can indeed take longer than that.

I'm pretty sure they have the ability to reduce the efficiency of the motor to generate more heat.
If the motor is 95% efficient then driving for an hour and a half would only generate 1.7kWh of waste heat.
1.5h*75mph*300Wh/mi*5%=1.7kWh

Excellent info! So on route preheat will most likely cause the motor to run more inefficiently therefore producing more waste heat that will intern heat the battery faster and to a higher temperature.

 

[YusufT]

Apart from this bring a ridiculous scenario, this won't happen. Like others have pointed out, there will be a minimum SOC required for it to function. From the map, you can see how many stalls are available so you shouldn't be running into a full station.

Or you know you can drive to the supercharger without putting it in your gps?

 

[SammichLover]

Excellent info! So on route preheat will most likely cause the motor to run more inefficiently therefore producing more waste heat that will intern heat the battery faster and to a higher temperature.

Yes as that's the only battery heater that the Model 3 has, using the temperature control coolant loop to draw waste heat from the drive units (the electronics and the motor itself) and transfer it downstream (as that's the direction the coolant flows in the loop) to the pack. Contrasting pretty much all other designs of battery heaters being based around resistive heating elements embedded in or along a side of the pack.

 

[AlanSubie4Life]

FWIW...

Elon Musk on Twitter

"Very little power & only right before you get to the Supercharger. You won’t notice it in range."

Elon Musk on Twitter

"Net power to warm pack is especially low when motors are running, as coolant loop routes motor heat to the pack when outside is cold (& rejects motor heat to air when outside is warm)"

He also said V3 beta for 3-6 months to get rid of any corner issues, so I would expect about 1 year minimum before rollout and 2 years before V3 are widespread. Obviously that's distinct from the pre-warming which should be available soon and hopefully will really help.

 

[Dana1]

Whether A or B is further does not affect my assumption. Maybe they are similar distance from my starting point. But the distance between them is long enough that I should not let on-route-warmup work considering the availability issue.

If the battery needs the warm up, it needs the warm up. Plan accordingly. The similar thread are the folks turning off climate protection for their tablet to save 10 miles of range. It’s foolish, in my opinion, to risk damaging the car to squeeze a few miles of range. Drive slower to achieve better range if you’re that squeezed.