May 17, 2016
David99 For a few weeks now I have been using TM-Spy, a little app that shows data from the Model S that is not available in the normal UI. Out of interest I was keeping an eye mostly on battery temperature. I was surprised to see how the car seems to warm up the battery quite a bit all the way to 105-110 F. Definitely well above ambient temperature. In those last weeks the temperatures here in Los Angeles were between 60 and 80.
The app shows the temperature of the coolant going into the battery module and coming out. There are two separate sensors. It makes it possible to see if the car is trying to warm or cool the battery depending on what temperature is higher or lower. What I saw is when I started driving (after a few miles) the input temperature was always higher than the output, thus the car was actively heating the battery. The difference in temperature was small. Only 2-3 degree difference, but it stayed that way until the battery reached well over 100 degree F. It takes a while, so only on longer drives did the battery reach this temperature.
I was surprised why Tesla decided to bring the battery up to such a high temperature all the time. After several days of seeing this I realized that I had turned on 'Range Mode' a while ago an forgot to turn it off. So I turned it off. Now I saw that the car doesn't seem to heat up the battery as much any more. The battery temperature still goes up when you start driving, but I can see that the input temperature is lower than the output so the battery just gets warm on it's own from use, but isn't actively been heated on top of it. Driving with range mode off I have never seen the battery as high as 105, which was the norm when Range Mode was on.
To be sure I just did another test drive. After driving for 35 miles with Range Mode OFF the battery was at about 89 F. The input temperature was just 1 or 2 degree lower than output. I switched to range mode, and within 2 minutes I saw the input temperature climb up 3-4 degree over the output and over the next 20 minutes the battery started to warm up to 98.
I highly doubt the car turns the battery heater on. I think what happens is that when in range mode, the car directs the coolant through the motor and inverter and then directly into the battery. The inherent losses of the motor/inverter are used to warm the battery to about 105. A warmer battery has a slightly higher capacity than a cooler one thus giving the car a touch more range. It makes sense to have a warmer battery when trying to get the maximum range.
I don't have a lot of time to do all sorts of tests, so I'm hoping others with access to the CAN bus can do their own tests and hopefully verify what I found. I do believe when the battery is below a certain temperature, it will always start warming it up, regardless of what Range Mode is set to. The only difference might be that when Range Mode is turned on, the car will bring the battery temperature higher than without it. Maybe it is different with newer cars with dual motors. Mine is a 2014 RWD 85.
I did read that Range Mode will prevent the battery heater (a separate energy sucking electrical heater) from coming on, which ends up being counter productive when the car is charging and plenty of power would be available.�
May 18, 2016
GlmnAlyAirCar Interesting observation. I will check later today if I can reproduce your findings.�
May 18, 2016
scaesare Interesting indeed.
It would seem to agree with the "max power" setting (or whatever it's called), that can be used with Ludicrous mode in order to squeeze the most energy out of the pack... that appears to heat the pack up as well.
I also believe that user okishira here also noted that internal resistance on the cells continued to fall as they got warmer up to relatively high point. That ultimately wastes less power.
The question them becomes: if the battery performs better when warmed like that, and the heating is "free" waste energy from the drive unit, why does it not also do that for non-range mode operation? My instinct is that, while it's better for performance, it may not be as advantageous for longevity.�
May 18, 2016
GlmnAlyAirCar My thoughts exactly. This would imply there are drawbacks to range mode other than cold feet.�
May 18, 2016
zambono Could it also be that range mode reduces cooling both for the cabin and components to conserve energy thus it warms up�
May 18, 2016
David99 Yes the internal resistance drops as the battery gets warmer. It helps with performance and it helps with efficiency thus range. But for sure keeping the battery warmer will increase degradation a little bit.
According to Tesla Range Mode reduced the cabin heater and AC to save energy. I definitely noticed that driving in hot weather.�
May 18, 2016
Canuck I've done this a lot since I go on trips most weekends.
I hope this isn't true but I can see the reasoning. If it is true, it would be nice to an icon in our dash alerting us when Range Mode is on, in case we forget, so we can turn it off when not needed.�
May 18, 2016
David99 I agree, it is definitely something you don't want to keep turned on all the time. But at the same time Tesla doesn't want the owner to be scared that a feature is 'bad for the battery'.�
May 18, 2016
supratachophobia Is it actively heating it up or just not actively cooling it as much as it could have? In other words, is it limiting the cooling on the input side and the end result is a warmer battery?�
May 18, 2016
Canuck I don't think an icon showing it's on in the dash would scare the owner. Rather, the owner would think it's there because the heating and cooling of the cabin is less effective when it's on, so it's there just to make sure you really want it on to extend range.�
May 18, 2016
deonb It would be a good icon to have anyway just for that reason.�
May 18, 2016
andrewket The UI used to show "ECON" on the climate controls when in range mode.�
May 19, 2016
GlmnAlyAirCar I seem to recall from photos of various diagnostic screen that have been posted to this forum that there is both an "active" and "passive" heating target (or is passive just for cooling; I don't remember). I would think it would only be the passive target that is raised in range mode.�
May 19, 2016
supratachophobia Sounds like range mode in the long-term may not be the best for the battery. At least, based on information publicly available that batteries tend to not like higher temperatures. So the worst scenario would be a hot day, with a full battery, with range mode on.�
May 19, 2016
David99 That's exactly what I think.�
May 19, 2016
David99 Since the input temperature is 3-4 degree higher the output temp is lower after it went through the battery it can't be the battery warming up itself.�
May 19, 2016
Canuck Our Leaf (with no thermal management system) gets dramatically better range in the summer. It's amazing the difference a warm battery can make when it comes to range.�
May 19, 2016
mkjayakumar So i guess in that situation hopefully the battery will not heated even more, because it might already be hot enough to get the maximum range out of it.�
May 19, 2016
AmpedRealtor I highly doubt that using range mode will have any negative impacts whatsoever on battery longevity or degradation. Tesla already warns you if you charge to 100% too many times, they do not have an aversion to warning the owner. I would have to believe that if range mode had negative impacts, we would receive a similar warning after using range mode too many times.�
May 19, 2016
apacheguy Right. Never ever use range mode. It bumps the passive cool target from 30 to 40 C. It's a stupid feature.�
May 19, 2016
AmpedRealtor But isn't range mode the only way to get full torque sleep in a dual motor car, or have they changed the implementation?�
May 19, 2016
David99 Warmer temperatures do make the battery age faster, that's a well known fact. By how much is really hard to say. Obviously 10 degree difference are not a big difference. And since we drive the car only for an hour or two a day and it sits for the rest of the time, the impact is probably very little. And if you live in Arizona, your battery is boiling all the time anyways LOL�
May 19, 2016
AWDtsla This is really unfortunate. "Range mode" does way too much stuff. You should be able to do things like not wasting energy on the battery heater and allowing for torque sleep without breaking climate control or cooking the battery in the summer.
It still is. But if I were in charge of the feature I'd make it transparent. It's not very difficult, I think, For example, if select normal performance mode i.e. sport on a P90D, then force torque sleep on. Also if you've entered cruise mode and/or there haven't been aggressive throttle inputs in n seconds, then enable torque sleep in any mode. Where n is a learned value based on previous transitions to and from aggressive throttle inputs. Of course, if you could just improve torque sleep to the point where there is no on latency, then there is no need for a mode switch at all.
Why should any of this have anything to do with other ways of increasing range/decreasing consumption? I'm still a little miffed by why If I drive for 15 minutes in cold weather, I have to have a 5kW battery heater running for 10 of those minutes. Just in time to park and let the car cool down again.... and repeat tomorrow.�
May 19, 2016
David99 I believe the resistive battery heater only comes on when the battery is very cold and the energy gained from a warmer battery is greater than the energy 'spent' on heating it. But then, as your example shows, when the drive is short the energy is more or less wasted. The car doesn't know how long your drive will be, though.
Maybe Tesla should do what every other EV has, an eco-mode. People understand and assume that in Eco Mode the car would not perform quite as well but would use less energy. Even non technical people get that.�
May 19, 2016
AWDtsla They should just expose them all as settings. Most of my winter I want no battery heater (maybe unless only when plugged in), full cabin heating, and torque sleep on. Not a possible combination right now.
Option A is the car is smart enough to do the right thing in all scenarios. Option B is give the user the option to select the right things. Unfortunately they went with option C: just pretend the car is smart enough to do the right thing and have few options.
Other cars have no problem having an eco mode for climate control that's separate from eco mode for the powertrain.�
May 19, 2016
supratachophobia We don't know this for sure. But on the other hand, we do know what hotter temperatures do to batteries. Just because Tesla doesn't say something about it one way or another, doesn't mean we can discount what we know about batteries already.�
May 20, 2016
SUN-day Driver Tesla should definitely say more about what Range Mode does. Last time I was worried about having enough charge for my trip I thought of the Range Mode setting and there's an icon for an info popup about it so I pressed it and it only said in Range Mode cabin climate control may be limited. Since it was nice weather that evening I wasn't using climate control so I didn't bother enabling Range Mode as I thought it wouldn't help (and I can turn ff climate control myself). I made it home but with my white knuckles may have been spared if I had info that Range Mode does more than limit cabin climate control.�
May 21, 2016
StaceyS Range Mode is what gets me to and from some of my further flung project sites in Eastern Oregon where there are limited charging options. When you're driving 180 miles out to some remote town and have to spend time on the only RV campsite with a 50 amp plug just to get home again, you become very aware of how much electricity Range Mode saves.
But for just running around town, sure, its probably not necessary. Now that we're coming out of winter (yes, I went skiing today!), I'll probably turn range mode off for the summer, as its really the heating in winter that kills range.�
Jun 5, 2016
Andyw2100 I imagine you realize this, so I'm pointing it out mainly for others. I have to believe a much larger factor in your Leaf's improved range in the summer vs. the winter is the fact that warmer air is less dense. Your Tesla, which does have a thermal management system, also probably gets much better range in the summer. (I know mine does.)
I believe that is still the case. I have not seen anything to indicate that range mode is no longer required to maximize the benefits of torque sleep.�
Jun 5, 2016
David99 I have been monitoring the battery temperature more since. Driving in hot weather and especially when Supercharging, the battery often get's warmer than 30 degree C. The car always seems to warm up the battery to around 30 C in normal model. In range mode it aims for 40 C. But when driving in warm climate the battery itself gets warmer on it's own. So in warm climates there is little difference driving in Range Mode or not.
Supercharging heats up the battery rather quick. On a trip through Arizona last weekend I saw the battery go up to 52 C.�
Jun 7, 2016
GasKilla I'm so confused by all this ... I've left my car in range mode for the torque sleep advantage. I'm in SoCal so the temperatures are relatively mild but my garage gets hot in the summer. I plan to keep my car for many years and don't want to prematurely reduce battery life. So I'd love to know what is best for longevity. Plus I've noticed since my last update that the A/C fan will go up to 11 in range mode but in the past it was limited to 8 or 9. That said I don't think the A/C is really reduced anymore�
Jun 8, 2016
wdolson I believe the A/C compressor output is limited in range mode, but they will run the fan at full in range mode now.
When I took delivery yesterday we discussed the implications of range mode and I was told that it really is best used when temperatures are mild, though I doubt using it for relatively short periods at other times (such as just on a road trip) would harm the battery all that much. He did say it shouldn't be left in range mode when the weather was too cold or too hot.�
Jun 8, 2016
Nevek This is a subject I'd like to see JB Straubel give an update on, perhaps as part of a bigger outline on battery heating, cooling and torque sleep.�
Jun 8, 2016
jgs Are the motor/inverter actively cooled? If so, then might there be some energy consumption advantage in cooling them by dumping the heat into the thermal mass of the battery instead of whatever other cooling system is used when range mode isn't active?�
Jun 8, 2016
supratachophobia I'm trying to work through this and figure out how it fits into my observation of increased efficiency by driving faster (80+) on hot days. If the passive cooling target was increased and therefore no battery power being spent on cooling, the driving faster would take care of the cooling and better efficiency at higher speeds would be observed. At least that's been my observation.�
Jun 8, 2016
AWDtsla I'm starting to doubt range mode for range. Starting to play around with having it off to see how bad it is, except that when I had it off, I beat evtripplanner by a wider margin that with it on! hmmm
�
Jun 8, 2016
apacheguy The only time I could see it making the slightest difference is when it's really cold. In summer time, it doesn't really provide much, if any benefit.�
Jun 8, 2016
David99 Definitely. The motor and inverter are liquid cooled and that energy can be used to heat up the battery. It is also used in cold climates to heat the cabin. Of course motor and inverter losses are small so there is only so much available to heat the battery or cabin.�
Jun 8, 2016
Andyw2100 What are you basing this on?
Jerome Guillen stated very clearly and specifically that torque sleep benefits were maximized with range mode on. If you have facts that disprove Mr. Guillen's statement I'm sure we'd all appreciate your sharing them.
--
�
Jun 11, 2016
AWDtsla Did another comparison between range mode and non range mode, with climate control off, Almost entirely highway travel, one ludicrous merge, aiming for about 78mph, and I control for road differences by using evtripplanner fed with my actual trip time. 0 mph wind.
Start: range mode off, 45 psi starting, 49 psi ending, 343Wh/mi, evtripplanner estimate 382Wh/mi
Return: range mode on, 48 psi starting, 50 psi ending, 323Wh/mi, evtripplanner estimate 364Wh/mi
So range mode only got 1.2% better this time, but you'll notice that tire pressure was significantly higher when range mode was on, which probably alone accounts for 1.2%.
I should add, that at low speeds with range mode on you can still quite clearly hear the front motor under more torque.�
Jun 11, 2016
msnow I'm wondering if you or anyone else has ever tested driving a certain specific route for a number of miles with Range Mode on and then repeating the same trip with it off. I notice that on my 90D the Rated Range gauge on the IC only shows .37 miles more when charging to 90% with it on than if it's off. I'm thinking the algorithm that is used to get that can't be right. I would think real world driving taking advantage of torque sleep would be a more accurate number.�
Jun 11, 2016
jerry33 My experience with range mode indicates it's most useful in cold weather on short trips. Then it saves quite a bit of energy from not heating the battery. In summer it makes almost no difference. I haven't made any long trips in cold weather, but I understand from those who have that it doesn't make a lot of difference there either because the battery heating is only at the beginning of the trip.�
Jun 11, 2016
gavine In cold weather, depending on the length of the short trip and how much stop and go there is, range mode off might be better because the energy gained with regen braking that is allowed once the battery warms up can exceed the energy used to warm the battery. If you're just taking the kids to the bus stop, range mode on is best. Same if you're jumping right on the highway.�
Jun 11, 2016
jerry33 Assuming you've pre-warmed the car, there is not much regen lost during urban driving. Typically it's going to have a limit of around 30 kW or greater (at least that's how my car acts). Most stops in urban conditions don't exceed that limit. (If you live in Winnipeg or some similar place, there's not much that's going to help when it's -30). So I'm not convinced that the amount of energy recovered by regen is going to be more than the energy used to heat the battery quickly other than in edge cases or if you have a jackrabbit start and screeching stop driving style--then I can see where it might.�
Jun 11, 2016
eye.surgeon So does a Tesla. It's as much heating the cabin as it is battery efficiency that reduces range in the winter, for all EVs.�
Jun 12, 2016
bxr140 More investigation required.
Based on some tests I did last weekend (100+ degrees in CA), turning range more off definitely makes a difference on the consumption history graph as well as how quickly the range 'margin' depletes...mostly, I suspect, because It keeps the AC compressor from spinning at 'ludicrous speed'.
Differences on the graph are a few pixels in the averages--enough to see something--and a 2% loss of margin over a 20 mile stretch compared to the previous 20 mile stretch with range mode on. Your guess is as good as mine what a few pixles actually means on the chart, but if I do my math right, my 60 uses ~10% of its range over 20 miles. Losing 2% 'more' means I used 12% over that 20 miles, which means I incurred a 20% increase in consumption between range mode off/on.
I repeated this two more times [in slightly different circumstances] with similar results. I don't profess this a conclusive data set, but its enough to say there's something noticeable going on. To be clear, I don't believe range mode will make much of a difference in warm weather on classic MSes if AC demands are low.
I coincidentally had my car in for service this week and asked the tech about range mode--he said the compressor is limited to 3000rpms in range mode. Perhaps someone can verify.�
Jun 12, 2016
Andyw2100 ,
I don't know about anyone else, but I have not. On the trips I take I think it would just be too difficult to adjust for the differences due to temperature, wind, etc. I track every one of two particular trips we take, and there is already a lot of variability, so trying to break out differences due to range mode being on or off I think would be pretty hard to do.
I think it's important to point out, though, that you're talking about a classic, single motor Model S, where the benefits of torque sleep are not coming into play.�
Jun 14, 2016
jgs For that matter, my impression (that I'm not going to support with a citation just now, sorry) was that at high speeds (which is usually when range matters most) the greater density of cold air dominates the factors you name, for all vehicles.�
Jun 14, 2016
AWDtsla Heating is a massive draw, it's basically 11-12kW of capacity to draw, which when start a car that's been sitting in the cold actually happens for quite a while. Especially when you have real-world use of the car, not turning the car on, driving for as long as possible, and stopping. Real life turns out not to be a contest to road trip the farthest in your car, but for most people a minimum of 2 starts and stops, probably on average 3-4 start/stop cycles spread throughout the day with the car cooling in between.
If Tesla had better insulation of the pack, and more efficient heater like heat pump, maybe even a thermos to keep hot battery coolant if it becomes available, a lot of the consumption would go away.�
Jun 14, 2016
jgs Fair enough. And I like the thermos idea, has that been floating around or did you just hatch it? I do think there's a subtle distinction to be drawn, though -- do you want the car to be efficient because you want it to be efficient, period? (Presumably many of us do, it's one of the main motivators for EV adoption.) If so, your points are well taken. But, as far as efficiency for the purposes of range qua range goes, I do still think that the road trip scenario is the dominant case. At least in my experience I'm doing a bunch of short trips such as you describe, averaging a pretty high Wh/mi but driving few enough miles in aggregate that there's no risk of depleting my battery before the end of the day, or I'm doing a road trip where sometimes I'm pulling in to the next Supercharger with 10% in the pack. In the latter case, I think drag still dominates.�
Jun 14, 2016
AWDtsla Prius uses a thermos. When I'm getting something around 1200Wh/mi in the winter (mind you actual consumption is even higher than reported in trip meter) it's not exactly being environmentally friendly.�
Jun 14, 2016
jgs Wowie. I think I'm consuming a lot when I get into the mid four hundreds!�
Jun 14, 2016
jerry33 Not since the third generation.�
Jun 14, 2016
Jeff N Right, they only did the thermos bottle for the 2nd generation cars sold between 2004-2009 model years.
For the 3rd and new 4th generation cars they instead use "exhaust gas heat recovery" where they have a heat exchanger inline with the exhaust coming off of the gas engine that can be used to help quickly heat up the engine "coolant".
This helps to keep the engine operating under ideal temperatures that maximize combustion efficiency. It also helps to quickly heat the cabin since the same engine coolant is run through another heat exchanger in the cabin to provide passenger heat.
This is especially helpful for hybrids since they switch the engine off and on regularly and this helps them quickly heat up again when the engine is restarted.�
Jun 15, 2016
Lex Cold climate owners seem to all agree Tesla needs better cold climate tech and support...�
Jun 15, 2016
Lex ... not that it's not a delightful car to drive in the winter, so far. But some things were a bit troubling in my first very mild winter.
As for thread topic Range Mode, I only use it when I really want to maximize range on long trips. I just don't think too much about "mileage" or range at all, quite honestly, except on long distance jaunts, and then I make a fun game out of it. But that's me�
Jun 15, 2016
scaesare While this was surmised initially, it turned out not to be true. Cabin heat is resistive electrical only. Drivetrain waste heat is used to help heat the pack, however.�
Jun 15, 2016
msnow I'd like to see data that shows there's benefit to Range Mode being turned on and I'd like to see it in Rated Miles, kWh or some other metric I can easily see for myself on an app or on the car. I've tried both on and off for almost a year and the benefit increase is negligible.�
Jun 15, 2016
David99 As far as I know the Model S has a heat pump to heat the cabin. It definitely uses the heat from the motor/inverter.�
Jun 15, 2016
AWDtsla No, and No.�
Jun 16, 2016
AmpedRealtor No heat pump.�
Jun 16, 2016
Lex But yes to coolant running through the motor shaft, no ? It's one of Tesla's patents... though I wonder how much it actually affects the coolant temp.�
Jun 16, 2016
zdre This is a big disappointment for me. I have had Range Mode enabled since delivery 3 years ago. I had no idea it affected battery temperature management at the high end. I am now at almost 40,000 miles and the degradation appears to be around 6%. I really wish Tesla documented their features better so customers can make appropriate decisions.�
Jun 16, 2016
msnow While I agree 6% is a lot I doubt very much that having Range Mode on caused any problems to your battery. My guess is you need to balance/calibrate to see what you really have in Rated Range.�
Jun 16, 2016
AWDtsla Temperature is almost directly proportional to degradation.�
Jun 16, 2016
AWDtsla It can only cool the motor or warm the battery.�
Jun 17, 2016
Lex Yes, I was curious about just how much the coolant mass is affected by this part of the system and my guess is "not really enough to help warm the pack enough to matter much" but instead "plenty enough to help the motors last longer than 25,000 miles each."�
Jun 17, 2016
AWDtsla Pretty much exactly the same amount removed from the motor/inverter goes into the battery pack. 30kW cruise with 95% (for example) efficiency? That 3*.05=1.5kW of excess heat going into the pack. Of course the efficiency is not fixed, I'm sure it's well under 95%, for example under hard acceleration.�
Jun 17, 2016
AmpedRealtor Better avoid "Max battery power" then... I suppose that also causes degradation without Tesla warning owners?�
Jun 17, 2016
ReddyLeaf There are PLENTY of Leaf owners, myself included, who would love to have 6% degradation after 3 yrs!�
Jun 20, 2016
zdre I was actually seriously considering the Leaf. The lack of active cooling was one of the main reasons I bought the Tesla instead.�
Jun 20, 2016
AWDtsla Yes. Although I think it does warn you.�
Jun 21, 2016
AmpedRealtor It warns about degradation? I didn't know that.�
Jun 21, 2016
Bankroetlama Are these your personal assumptions or proven facts? Does Tesla heat up the battery, or simple stops with cooling it.�
Jun 21, 2016
supratachophobia I think the general observation is that it doesn't cool it as much. But i could be wrong.�
Jun 21, 2016
Bankroetlama It is a very important distinction!
If Tesla heats the battery, it would mean a warmer battery is better.
If they stop cooling the battery, it means that a warmer battery is worse, but that they don't want to use extra energy too cool it in range mode.�
Jun 21, 2016
wdolson Most Li-Ion batteries are happiest at 20C (68F). If temperature goes much above or below that, it can affect performance and even damage the batteries if the stress goes on too long. They can't keep them that cool most of the time without some kind of refrigerant, but with range mode off the system does as much as it can to regulate the temperature.�
Jun 21, 2016
jerry33 In the winter selecting range mode reduces the amount of pack heating by quite a lot. The heaters don't come on unless needed to protect the battery. It's easy to see this behaviour as you can start one morning in range mode and one without range mode and watch what the Wh/mil do. In summer it's harder to see what happens, but I suspect it's the inverse of winter. e.g. the battery is allowed to get to the maximum allowable temperature before the compressor is turned on. In summer I've never found range mode to do all that much, so I don't bother with it.�
Jun 25, 2016
Lex But for those of us with D model it seems to do more with the front motor... only adding to the votes for "sure wish we knew exactly what these buttons do".
And yes I know it says torque sleep or some other specifics is in the manual or guides or on screen etc.�
Jun 30, 2016
apacheguy I have pretty good evidence that Tesla changed the passive cool target to 40 C for all cars even with range mode off. Odd.�
Jul 3, 2016
David99 What is this based on? I would love to hear your findings.
I have been keeping an eye on battery temperature for a while now and noticed that it always starts heating the battery when it's below 30 degree Celsius but switches to cooling once it gets over 30. But, it doesn't seem to make any strong efforts to keep it down. Depending on outdoor temps and driving it often goes up to 40 or even higher. I have to say that all my experience since I was able to monitor temperature have been in warm climate.�
Jul 3, 2016
robby I too would love some data on this. I leave range mode on at all times to get the best efficiency. I'd appreciate any quantitative data folks have that informs whether I'm putting significant stress on my battery.�
Jul 3, 2016
David99 Here are my 2 ct.
I live in OC/Los Angeles where it's always warm or hot. Most of my trips are to even hotter areas like Las Vegas or Arizona. So I definitely have my car exposed to higher than average temperatures all the time. I also drive a lot which heats up the battery as well. After more than 2 years and 81k miles my degradation is very low, better than average. So warm temperatures can't be so bad for the battery.
Obviously storing it at cool temperatures would be ideal, but a cold batter is not efficient. To perform well and get good range the battery does much better when warm. The fact the Tesla decided to warm up the battery tells us it must be the better choice.
We have two opposing ideals. Cool temperatures are good for the battery's long life. Warm temperatures are best for efficiency. Based on my experience I would say Tesla found a good compromise. We are all concerned with degradation, but the data shows that even in less than ideal conditions degradation isn't much of an issue. I Supercharge a lot, I drive a lot, I constantly have my car in hot temperatures, I don't baby my car. My degradation is less than 5% and it has stayed the same since the last 30k miles. So it seems after the initial drop, degradation is very small and I don't think it's a concern at all.�
Jul 5, 2016
apacheguy Last time I checked, the battery temp was 37 C and inlet and outlet coolant temps were all jumbled for each of the modules. Usually the outlet is warmer than the inlet when passive cooling is occurring. Range mode was definitely off.�
Jul 14, 2016
apacheguy Following up with further evidence, last night the MS battery temp increased from 33 to 36 C while charging at 240 V/40 A. It certainly was not cooling the battery during this period.�
Jul 18, 2016
Electric700 I think that the heating you're referring to when the outdoor temperature is high (e.g. 90 F/32 C) is the heating that occurs while driving, since the battery's electricity transfer and motor's rotations naturally increase the temperature of the system. The heater is only turned on when the outdoor or battery temperature is low, for example when it's below 40 F/4 C. I'm not sure what the actual threshold is though.
So, it makes sense to me that the coolant line temperature input to the battery pack/charger(s)/motor is lower than the output temperature when it's hot outside, since the coolant is removing excess heat generated by the system. In the winter when it's very cold, the coolant line input temperature might be warmer than the battery pack/charger(s)/motor, so the output temperature might be cooler until the system heats up to the ideal temperature through a combination of driving + the heater being activated.�
Jul 23, 2016
hiroshiy On a slightly side note, have you noticed increased power usage with Range mode OFF, after the update? I have seen approximately 10% increase. With Range mode ON the power usage seems similar to me.�
Jul 23, 2016
msnow Are you noticing that on the Energy app or just a feeling? I haven't noticed any change in power usage but to be fair I haven't focused on it.�
Jul 23, 2016
jerry33 For me there's no significant difference except in the winter, when range mode reduces the amount of battery heating on short trips.�
Jul 23, 2016
hiroshiy Thank you, @msnow and @jerry33. My observation is from the numbers from the trip counter. Usually, I drove like 120km/h and above (speed limit 100) and I got 190Wh/km - 200Wh/km, either Range mode was ON or OFF.
A few weeks ago I changed tires and wheels from 19" cyclone Michelin PS3 (not PS2 in Japan), to 20" 255/40R20 Bridgestone Potenza S001. Since then I experience 10% increase, like 220Wh/km with range mode OFF, as I saw this thread. Today I turned the range mode ON to see the difference. To my surprise the consumption was now back to 190.
That's why I thought something had changed with range mode OFF...�
Jul 23, 2016
Matias It should also have "Advanced" settings -tab, where geeks like us could fine tune settings any possible way�
Jul 23, 2016
KJD What is the circumference of your 20" tires compared to your 19" tires?
If they are different you have thrown all of the calculations off.�
Jul 23, 2016
hiroshiy I think 255/40R20 gives 1% more circumference than stock 19.�
Jul 23, 2016
Matias Please read the first post. In range mode coolant that enters the battery is warmer than coolant that exits the battery. So it is warming the battery.�
Jul 23, 2016
jerry33 1. New tires have more rolling resistance than worn tires because there is more squirm in the tread compound.
2. As rim diameter gets larger and aspect ratio gets smaller, rolling resistance goes up, all things being equal (which they often aren't).�
Jul 25, 2016
hiroshiy Thanks again, @jerry33 .
I read JB's blog post about new tires causing more rolling resistance and higher power consumption around 5% (!!) for up to 1000 miles. Also as you mentioned I agree 255 is wider and will cause more RR.
Since Tesla said moving from 19" to 21" gives 3% more RR, moving from 19" 245 to 20" 255 also might give 3% more RR.
Also I changed tire from PS3 to Bridgestone S001 (very sticky tire), so this will also cause more RR.
In total 10% more consumption may be just my configuration, not by firmware change or range mode.�
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