If preconditioning is so good and important..... why no dedicated button?

[hybrid2bev]

What I'd really like to see implemented is a simple add: an indicator on the display when the battery is preconditioning for DCFC charge.

+1 for this!!

+1000 if we could have a button to manually start preconditioning while in route (greater than 18 miles away from the chargers).

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[voxel]

I'm in Florida, I don't care for preconditioning.

In fact, with my former Teslas... I intentionally did not navigate to Superchargers to AVOID preconditioning as it would waste a ton of energy (crushing efficiency) and maybe speed up DC charging a few minutes.

A dedicate button might be useful if I was on a long road trip and it was chilly.

 

[Sam2084]

Unless you're monitoring it via the OBD then you wouldn't even know if your battery is up to temp. There's nothing in the car that would tell you that. As for "that's the whole point" ... I don't buy it until I see the facts to back it up. Even if it does provide a greater time savings at what point (temp) does that no longer apply? In 30-40ish degree temps the battery, on a DCFC, is 95F in very short time. I don't have sub-zero temps where I am to test lower temps.

While I did not monitor it via OBD, I know what the charging curve is and I know I was well below it for the first 20 minutes. It takes a lot of time to warm up 1000lb of battery 60 degrees with a 4kW space heater.

I understand why you’re skeptical, and I’d like to look at more qualified data for the Mach E as well but this is a proven concept that is widely agreed upon as important and helpful for EVs. Im sure you can find a ton of the preconditioning data in the Tesla or ioniq 5 forums since the effect of preconditioning is more drastic in those vehicles.

I don’t think the ambient temp being higher will cause the time savings to go negative because the closer the temp is to ideal, the less energy is spent warming the battery. Naturally though, in colder climates the effect of enroute battery preconditioning will be more noticeable.

 

[DevSecOps]

...but this is a proven concept that is widely agreed upon as important for EVs

I'm too critical of a thinker to sheeply accept that. I could point out many things that we widely accepted as factual/important/scientific that are complete BS. Additionally, while it might be "important" ... important to who? Someone who lives in Alaska or someone who lives in Florida?

One of the reasons that Tesla drivers originally recommended preconditioning was because superchargers were free and it didn't cost anything to waste those electrons. So, therefore it was a "why not?". The Ionic 5 is a different vehicle all together and charges at a much faster rate than the MME, in which, yes, that would likely make more of a difference.

All my original comment was in regards to was facts. I want to see the factual data. I want someone to test it. I don't want "well Joe told me so," or "based on time spent in Walmart" or "Juan's YouTube video said". If I lived in a cold climate I would do the test myself, but I don't. If preconditioning does absolutely nothing at 40F+, as an example, that would be nice to know. I'm sure there's a delta where it swaps from beneficial to a waste of time and money. Where is that? @voxel post is a good example of why not to use preconditioning and there's many forum posts on other EV forums that question the validity of preconditioning.

There are many, many posts of mine where I went to DCFC and logged data for this forum. The original charge curve changes were first documented and logged by myself. DCFC 150 vs 350 etiquette was documented, logged and charted by myself. When people comment asserting fact I like seeing it backed up by the data.

 

[Rt1AWD]

How to control the state of the battery with OBD?

 

[bbulkow]

I really think there should be a button, and everything else is communication.

The button should be labeled "decrease range"

"Press here to reduce your range by 10 miles but maybe increase fast charging speed by 10% depending on charger type"

There are plenty of fast charging situations you don't want to lose that range, like going to a fast charging location that might be broken or down, if you don't have a couple of backup spots.

 

[Mach-Lee]

All my original comment was in regards to was facts. I want to see the factual data. I want someone to test it. I don't want "well Joe told me so," or "based on time spent in Walmart" or "Juan's YouTube video said". If I lived in a cold climate I would do the test myself, but I don't. If preconditioning does absolutely nothing at 40F+, as an example, that would be nice to know. I'm sure there's a delta where it swaps from beneficial to a waste of time and money. Where is that? @voxel post is a good example of why not to use preconditioning and there's many forum posts on other EV forums that question the validity of preconditioning.

I do it for the driving dynamics. Even with the battery at 45ºF the acceleration isn't as good and you get less regen with 1PD. GTs probably get more jail bars. When the battery warms up above 70ºF there's a noticeable difference to me with acceleration and especially 1PD regen ability, the car stops in less distance. Yes, it uses more power to precondition, but power is cheap here and I don't care about the extra $5/mo. Different story in CA if you are paying astronomical 50¢/kWh rates to do it.

The climate in California is so mild you can probably get by without preconditioning very much, but when it's below 0ºF outside you really want that battery warmed so the car doesn't feel like a Prius. Also important for charging speeds on a trip.

So I would say optional if the vehicle is parked in 35-55ºF temps, and strongly recommended if the vehicle is parked in below 35ºF or above 105ºF temps. Not necessary at nice weather temps.

If you want the lowest electricity use possible then don't precondition.

 

[DevSecOps]

So I would say optional if the vehicle is parked in 35-55ºF temps, and strongly recommended if the vehicle is parked in below 35ºF or above 105ºF temps. Not necessary at nice weather temps.

I know the conversation that I had goes a couple posts deep, but I was mainly referring to preconditioning while driving to a DCFC via the nav. Those are the cases that I'm wondering about. I know for certain that high temps 100+ don't matter when the car is in motion because the cooling system will keep it at 95F. At lower temps when does it make sense to precondition while in route to a DCFC when the charge itself will cause battery warming. At what point does preconditioning use more power than it's worth at the charger?

As a completely made up example:

Ambient: 30F
Battery: 45F
Preconditioning uses 10kw to warm to 95F while in motion
DCFC for those lost 10kw will take 10 more minutes
DCFC for those lost 10kw will cost $4.80 more
DCFC without preconditioning would have been cheaper.
DCFC without preconditioning would take 5 minutes less to warm the battery when charging

The end result of the aforementioned would be better to not precondition in route to the charger. I know that there has to be a really cold temp where it would be beneficial and there's gonna be temps when it doesn't make sense. So where is that point? My original post was that I would like someone to test it, but I can't because of my climate.

 

[GreaseMonkey]

I'm too critical of a thinker to sheeply accept that. I could point out many things that we widely accepted as factual/important/scientific that are complete BS. Additionally, while it might be "important" ... important to who? Someone who lives in Alaska or someone who lives in Florida?

One of the reasons that Tesla drivers originally recommended preconditioning was because superchargers were free and it didn't cost anything to waste those electrons. So, therefore it was a "why not?". The Ionic 5 is a different vehicle all together and charges at a much faster rate than the MME, in which, yes, that would likely make more of a difference.

All my original comment was in regards to was facts. I want to see the factual data. I want someone to test it. I don't want "well Joe told me so," or "based on time spent in Walmart" or "Juan's YouTube video said". If I lived in a cold climate I would do the test myself, but I don't. If preconditioning does absolutely nothing at 40F+, as an example, that would be nice to know. I'm sure there's a delta where it swaps from beneficial to a waste of time and money. Where is that? @voxel post is a good example of why not to use preconditioning and there's many forum posts on other EV forums that question the validity of preconditioning.

There are many, many posts of mine where I went to DCFC and logged data for this forum. The original charge curve changes were first documented and logged by myself. DCFC 150 vs 350 etiquette was documented, logged and charted by myself. When people comment asserting fact I like seeing it backed up by the data.

That was me asking for a 150 vs 350 chart and your data was very helpful. I have similar questions about preconditioning, but I don’t drive enough to be able to collect this data.

 

[Mach-Lee]

As a completely made up example:

Ambient: 30F
Battery: 45F
Preconditioning uses 10kw to warm to 95F while in motion
DCFC for those lost 10kw will take 10 more minutes
DCFC for those lost 10kw will cost $4.80 more
DCFC without preconditioning would have been cheaper.
DCFC without preconditioning would take 5 minutes less to warm the battery when charging

The end result of the aforementioned would be better to not precondition in route to the charger. I know that there has to be a really cold temp where it would be beneficial and there's gonna be temps when it doesn't make sense. So where is that point? My original post was that I would like someone to test it, but I can't because of my climate.

Right now en-route preconditioning is so limited in duration you're going to have a hard time getting it to use more than 1 kWh extra unless you drive with the HVAC off (then <2 kWh). The whole point of doing it is so you spend less time at the charger. The arrival target is 78ºF, which would take 3.3 kWh and about 45 minutes en route to reach in your example. After you plug in it would heat the rest of the way to 95ºF. The Mach-E does not have a great charging curve, but I'd estimate preconditioning would speed up DC charging by about 15-20%.

So it would cost you ~$1.58 extra to save maybe 8 minutes on a 10-80% charge by preconditioning. It's also a LOT healthier for the battery to be warm while DCFC to reduce capacity loss.

If I had to make a cutoff point, I'd say around 40-50ºF battery temp is where you want to always use it.

Again, we haven't realized the full speed improvements from en route preconditioning because of how neutered it is currently (only 30 km ahead), and how restricted our charge curve is.

 

[DevSecOps]

Again, we haven't realized the full speed improvements from en route preconditioning because of how neutered it is currently (only 30 km ahead), and how restricted our charge curve is.

I've seen quite a few YT videos, from other mfgs, where preconditioning would have caused them NOT to make it to their destination because of the crazy amount of energy it uses. Other forums have had intense discussions about how preconditioning is a curse when in route to DCFC and we've seen a few people here share that same sentiment with their other EVs. That being said, Ford's way might be better in that it's neutered.

The one piece of data I wish I could get is how long does it take in X ambient to 85F battery (without preconditioning) on DCFC. Not guesses but actual data. When I've tested it from my relatively mild temps it only takes a couple minutes at most.

 

[Mach-Lee]

I've seen quite a few YT videos, from other mfgs, where preconditioning would have caused them NOT to make it to their destination because of the crazy amount of energy it uses. Other forums have had intense discussions about how preconditioning is a curse when in route to DCFC and we've seen a few people here share that same sentiment with their other EVs. That being said, Ford's way might be better in that it's neutered.

The one piece of data I wish I could get is how long does it take in X ambient to 85F battery (without preconditioning) on DCFC. Not guesses but actual data. When I've tested it from my relatively mild temps it only takes a couple minutes at most.

I think less than 5% battery used for battery heating is sort of the sweet spot. It does not use a crazy amount on the Mach-E, most people will use less than 3% to warm up. Just plan for that by subtracting 3-5% from your planned arrival % if using en route preconditioning. The car should also be smart enough to disable preconditioning if it thinks you’ll arrive to the charger with less than 10% left. Other cars have much bigger battery heaters than we do, so it would have a larger effect.

Time to reach 85F will depend on battery temp, charger input, and HVAC use. Hard to calculate. I have a table of time to reach 26°C en route though:

https://www.macheforum.com/site/thr...ing-taking-requests.24393/page-10#post-593898

Battery heats at about 5-6 kW with HVAC off and 1-3 kW with HVAC on.

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