Jul 9, 2012
Wattson Hi all,
I'm new here and haven't yet been able to find the answer to my question through the forum search feature. If anyone has any info or could point me to the appropriate forum, I'd greatly appreciate it. I've also considered that the info might not yet be available. I feel that I can make a more informed buying decision in the future with this info.
When Tesla advertises 40, 60 and 85 kWh battery pack capacities, are those the absolute capacity of the pack or the available capacity?
I've learned via the forum that the Model S will have two charging modes: Standard and Range. What is the user available kWh charge in Standard and Range in each of the three battery packs?
Cheers,
David�
Jul 9, 2012
ckessel Can someone actually confirm this? I've yet to see the car and not ever actually heard that the Model S will have selectable charging modes.�
Jul 9, 2012
Wattson I've seen it mentioned by several people in various threads. I found the best confirmation in this post.�
Jul 9, 2012
ckessel So, then the next question would be is 300 miles in standard or range mode? It feels a bit disingenuous to advertise 300 mile range (or EPA 265) if that range can only be reached by damaging the battery with range charging. If the listed mileage is only in range mode, that really cuts down effective range.
Take a 160 battery, use standard mode, freeway speeds, and give it a few years degradation and you get maybe 80 miles of realistic freeway range?�
Jul 9, 2012
Kevin Sharpe With respect, isn't that the same as the Roadster?�
Jul 9, 2012
smoothoperator Tesla recently changed their position from there only being one mode (standard) on the Model S to two modes. They must have seen degradation in the battery (after multiple trips where the battery was almost depleted) when only having a single mode and legal probably made them add range mode to cover their butts with a disclaimer about "using range mode + longevity of the battery." It is a recent & sudden development that Tesla implemented an additional mode on the Model S.�
Jul 9, 2012
Doug_G To be fair, Tesla previously stated that they hadn't decided on charge modes yet. So there's nothing "sudden" about the decision to include Range mode... they've simply decided.
For the Roadster Standard mode gives you 80%, BUT since it actually charges to 90% and hides the bottom 10%, you can always access the bottom 10% by tapping the touchscreen - an extra 10% "magically" appears.
It is woth noting that the Model S apparently doesn't need a Performance mode, unlike the Roadster. That's nice to see.�
Jul 9, 2012
ckessel Yes, but 99.99% of the people that will buy the Model S (over the next few years) will never have seen or know how the Roadster worked. They, like me, will simply come in and go "Wait, you mean I can't actually get the advertised range without hurting the battery?" Then, hopefully, would be a flurry of questions (the other possibility is the customer just leaves in annoyance).
How often can I charge in range mode before it does damage? How much damage? What does that mean for the warranty? How does that impact my lease if I use range mode frequently? etc, etc, etc
I'm pretty much in Tesla's corner, but I'd thought all this time the 300 mile battery was with a standard charge. I, in part, sold the concept of Tesla to my wife with the idea should could regularly make the 240 mile round trip Portland->Eugene->Portland without much strain, or the coast and back, but it sounds like that might not be true if I'll have to charge in range mode each time. In short, if 300 (EPA 265) isn't a standard charge that has some impact on my perception of the car's overall value.�
Jul 9, 2012
smoothoperator Before the "Rainbow Event" Tesla "Geniuses" were telling customers that there would only be one mode.�
Jul 9, 2012
Wattson So one potential answer to my question is that Standard mode allows 80% of the battery capacity to be used. Somewhere else on internet.com or this forum, I've seen the figure 3.5 miles per kWh thrown out for the average Model S efficiency. Using these figures, usable range is:
40 kWh pack
32 kWh usable
112 miles of range
60 kWh pack
48 kWh usable
168 miles of range
85 kWh pack
68 kWh usable
238 miles of range
Again, these are just estimates based on assumptions of 80% charge available in Standard mode and an average efficiency of 3.5 miles per kWh.�
Jul 9, 2012
Wattson Doug or anyone... What percent of the battery is made available to the user in Range mode on a Roadster?�
Jul 9, 2012
Andrew Wolfe Come on now. Range mode doesn't "damage" the battery. It just uses it up faster. Just like driving at maximum specs uses up tires and brakes faster. Nobody complains that "If I accelerate 0-60 in 4.4 seconds every day then I only get 4000 miles out of the tires," but that is probably the reality of the situation. Admittedly, batteries are expensive and thus everyone is oversensitive about them - but if you drive at 90-100% of range every day then you are driving the wrong car.�
Jul 9, 2012
smoothoperator 100% (10 char)�
Jul 9, 2012
brianman As I understand it, Range mode can damage the battery. But the scenario is more specific: charge it to full in range mode, and then leave it sit at that full charge for a day. That does damage to the battery.
Charging it to ranged mode and driving it down to "normal range" within a few hours of reaching full charge shouldn't cause undue strain on it though.
That's how I understood it from the Roadster engineer(?) post a bit back.�
Jul 9, 2012
Doug_G Tesla specifies the Roadster battery pack at 56 kWh, but elsewhere have stated 53 kWh.
The consensus appears to be that the pack is 56 kWh nominal and 53 kWh usable (in Range mode).
Also Range mode does NOT damage the battery. The rate of cell degradation is slightly higher than normal while the car is fully charged or nearly empty. By using Range mode judiciously the additional degradation is tiny. If you charge to 100% and then immediately drive off the pack gets back under 90% in short order, so the time spent in the extra degradation range is tiny. (It's actually better for battery balancing to leave it at 100% for a couple of hours once in a while.)�
Jul 9, 2012
Wattson Thanks all for your speculative answers. It seems so far that official usable battery figures are not yet available.
As for the average Model S efficiency of 3.5 miles per kWh figure, it seems supported by the second graph in this Tesla blog post.�
Jul 9, 2012
Wattson If 53 of 56 kWh is available in the Roadster, that would mean about 95% of the battery would be available in Range mode. Again assuming an average efficiency of 3.5 miles per kWh:
40 kWh pack
38 kWh usable in Range mode
133 miles of range
60 kWh pack
57 kWh usable in Range mode
199.5 miles of range
85 kWh pack
80.75 kWh usable in Range mode
282 miles of range
Disclaimer: The above figures are just some speculative math based on the context of Roadster usable battery charge and assumption of 3.5 miles per kWh efficiency for Model S
I'm a lot more comfortable with the numbers I've generated in this thread. The Standard and Range mode mileage estimates seem a lot more real based on facts available and reasonable assumptions.�
Jul 9, 2012
ckessel What's the distinction between "damage" and "impacts long term battery life" (the wording from the Tesla screen shot)? We're just talking semantics?
If Tesla is warning about long term impacts of range mode, seems like that leads to those various questions I mentioned.
Edit: (having seen Doug_G's post) Sounds like Tesla needs to have a very clear specification about what "long term impact" means with range mode or a great many people are going to assume it's essentially all but verbotten to use range mode at all. In my mind, I'm wondering "So, 1% damage each time?" I have no idea, neither does 99.99% of the rest of the population. Sounds like it's an education issue Tesla needs to jump way out in front of.�
Jul 9, 2012
stopcrazypp It doesn't work like that and it's not really possible to have a very clear specification to the general public (without them being willing to learn about the details of battery chemistry).
I'll refer you to wikipedia on lithium ion batteries. A laptop cell stored at 100% SOC loses 20% capacity per year. Stored at 40-60% SOC it loses 4% capacity per year. That's what Tesla means by long term impact.
http://en.wikipedia.org/wiki/Lithium-ion_battery#Disadvantages
What matters is not what happens "each time". What matters is how long the battery is stored at or near 100% SOC. So if you charge in Range Mode and use up the charge almost immediately, the long term impact is negligible. But if you charge in Range Mode and store the car for long periods of time (I'm talking about weeks, not just days) near 100% SOC, then the impact is huge. And it's very hard to quantify this in specific numbers (esp. because the relation is not linear).
And Doug G makes a good point that this is not "damage". This is just accelerated degradation (which happens even if you pamper the battery). You can think of it as extra "wear" (like Andrew's analogy). Damage is something like over-voltage or under-voltage (which would make the battery cell completely unusable, see the whole bricking controversy).�
Jul 9, 2012
ckessel Well, Tesla's going to need to find a way to make that discussion possible because people are going to want to know and they'll feel very uncomfortable and untrusting with vague answers.
Then that sounds like the educational material Tesla needs to put together. I'm not trying to be a hardass here, people are going to want to know. George B even talks about how the stores are about educating people on EVs. This seems like a good fit of purpose.
This is just quibbling semantics. It all boils down to "I do X and the battery gets worse by Y". Very few people, including fairly technical people like me, are going to care about the technical classifications of why Y gets worse. You might argue they should care, but that's fighting human nature and that battle is lost before it's started.�
Jul 9, 2012
stopcrazypp The problem is most people don't give a sh*t about these specifics (you can tell by how much the general public knows about ICE cars). Some people are enthusiastic (like us), most people don't care. You can see the battery bricking issue for a fine example (Tesla laid out a very clear description of the discharge timing in the manual that was largely ignored).
It's not just "semantics". "Damage" is orders of magnitude worse than "wear" and is usually used to describe issues that lead to the need for immediate total replacement or repair of a part, which is why it's not used except in very specific situations. For example, there are certain roads that put extra wear on tires, but you would not call it "damage". However, if a nail punctured your tire, it would be called "damage".
In the same vein, charging in Range mode (and storing it for long periods of time, like the worse case I point out) would not lead to your battery needing immediate replacement or repair. The battery will just wear faster than normal. As in your 1 year old battery looking as if it's a 3 year old battery. However, if you fully discharged it and left it there so that it is under-voltage (this is real damage), your battery would need replacement or repair.�
Jul 9, 2012
ckessel Smoking damages my lungs.
Lack of oxygen damages the brain.
Pollution damages fish runs.
Bruising damages the apple I'm going to eat for lunch.
I do understand what you're saying, but it's common for "damage" to mean "diminished capacity" or "excessive wear". In Oregon, there have been numerous articles over the years about how studded tires "damage" the roads though it's basically excessive wear.�
Jul 9, 2012
smoothoperator Tesla Roadster Battery Care�
Jul 9, 2012
brianman Yah, that's the post to which I was referring.�
Jul 9, 2012
gg_got_a_tesla Dan Myggen appears to have moved on recently to a role as a Training Developer at Tesla; given the quality of that response regarding the Roadster battery, that augurs well for Model S owners.�
Jul 9, 2012
kevincwelch I'm with ckessel on this one.
The Model S is not the Roadster, so while it is nice to project the outcome of the Roadster on the Model S, it isn't going to be accurate. I think the reason why this battery issue is such a polarizing issue is purely because Tesla hasn't been very forthcoming about it the whole issue other than to sheepishly admit that the Model S hasn't been around long enough to test the battery.
To put this issue at rest, Tesla needs to do the following:
1. Give us the warranty in plain writing.
2. Specify what constitutes normal use.�
Jul 9, 2012
Doug_G Dan is now in charge of training the guys who will deliver your Model S's.�
Jul 9, 2012
Doug_G Funnily enough when I've got a full Range mode charge, my log parser also shows SOC at 95%.�
Jul 9, 2012
EarlyAdopter FWIW, running an ICE car down to near empty before every fill can over time cause problems, too.
The reasons are varied - impurities floating to the top, sediment settled at the bottom, more air volume for water vapor to condense - but the impact to the fuel system and engine is said to reduce fuel efficiency over time, thus range.
As a precaution I try to refill my car when it hits a 1/4 tank, so my range is cut by 20-25%, too. Seems reasonable to me to do the same with an EV.�
Jul 9, 2012
smoothoperator If you ran a Tesla Roadster (cannot comment on the Model S since no data is available but I would assume it would be similar) to this point (before every fill i.e. charge), irreversible battery damage would occur. In an ICE motor you would likely only have to change the fuel filter.�
Jul 9, 2012
stopcrazypp All of the examples you give have extremely bad connotations and have immediate results you can see when you examine the "damaged" subject.
Lung damage from smoking can be immediately seen from the damaged cells in your lungs.
Brain damage from lack of oxygen can be immediately seen from dead brain cells.
Pollution damage on fish runs can be immediately seen from order of magnitudes more dead fish (not natural deaths).
Bruising damage on your apple can immediately be seen from the brown marks.
This is not the same as what you call "damage" when charging in Range mode. The only sign is the battery looks older if you do it regularly (there will be no measurable immediate results). There's no evidence of "damage" at all. The battery is still operating in its normal window of operation (0-100% SOC). While in a over-charge or over-discharge situation, you will see immediate "damage" (swelling or venting of cells, immediate lost of a couple percent of SOC and continued accelerated loss afterwards even in normal charging conditions, higher impedance and thermal instability).
The closest point you have is the example of excessive wear of studded tires, although from what I can tell, the wear from studded tires can be an order of magnitude worse (requiring in the worse case, annual or biannual repaving vs. the 14 and 25 year life span of Oregon asphalt and PCC roads) and they use "damage" to describe it clearly because it sounds (and implies) much worse than just "excessive wear". Plus studded tires can actually chip at the pavement (not just rub against it).
http://preservingoregonsroads.org/wp-content/uploads/2012/03/UseEffects.pdf�
Jul 9, 2012
ckessel
Fine, if you feel you have to "win", then I concede.�
Jul 9, 2012
W8MM Why can't we just admit that EV battery packs are wear parts, just like clutches and brake rotors, pads, and shoes, and tires?
They wear out. Are brake rotors "defective" when they reach end of life?? Or, are they just worn out because of usage patterns?
I, too, think that characterizing consumption goods as infinite-life investments is the wrong way to think about them. Your choice of debate terms reveals an insight into your thinking over which nobody is trying to "win", maybe just enlighten.�
Jul 9, 2012
ckessel Yep, I'm fine with that. I even said I understood the point and my only point was that a common meaning of "damage" is fairly analogous with degradation.
FWIW, Websters: damage[verb] - to reduce the soundness, effectiveness, or perfection of.
Does range charging reduce the soundness, effectiveness, or perfection of the battery?�
Jul 9, 2012
ddruz Remember, we do not know yet whether the 60 or 40 kwh cars weigh significantly less than the 85 kwh car on which we have data. If they do, the miles/kwh will be proportionately higher for the smaller battery pack cars. For example, my Leaf which weighs about 3350 lbs easily gets 4.4 miles/kwh and can get over 5.0 miles/kwh if I drive conservatively.�
Jul 9, 2012
EarlyAdopter Not according to the folks at Edmunds:
The lower your car's gas level sinks, the more the dirt gets stirred up from the bottom of the tank. Drive on a near-empty tank and you risk this dirt getting into your car's fuel line and even into the engine. There's a good chance your car's fuel filter won't be able to catch all of it, especially if you drive with a barely filled gas tank on a regular basis.
"You're going to pull the heaviest sediment into the fuel line," says Karl Brauer, editor-in-chief at Edmunds.com. "If it gets all the way to the engine, it could scar or damage internal parts of the engine."?
From: Bad driving habits can wreck your wallet
�
Jul 9, 2012
Lloyd Also the newer "in the tank" pumps depend on fuel for cooling. Pumps that are run near empty have been purported to have a shorter life span. Replacements are also more expensive. Chevy now requires replacement of the tank as well as the pump. $500+ and several hours of labor.�
Jul 9, 2012
smoothoperator How does sediment get past a filter? you may see a restriction or perhaps if someone pokes some holes in the filter? If the sediment is small enough the secondary fuel filter will catch it, no? Using your scenario lets say that this is true....Do you believe that running on low fuel consistently will cause as much damage to an ICE motor as it would (running a low SOC cosistently) with an EV? I have never seen a warranty document from a major auto manufacturer that states that if you run your vehicle on a very small amount of fuel consistently your warranty is voided (or if you run out of gas consistently). I have seen a document from Tesla stating that if you do not plug your vehicle in your warranty is voided and that you may cause irrepairable unwarranted damage to your battery. Please advise�
Jul 10, 2012
jerry33 1. In modern cars the fuel is pumped from the bottom of the tank. There is really no place for any dirt to settle--except in the fuel filter.
2. The fuel pumps in modern cars don't just keep running when the tank is empty and burn out (some early ones did, but that was years ago).
This is another topic, like tires, upon which there is a lot of garbage floating around. What was true in 1930 era cars isn't generally true today.�
Jul 10, 2012
Vger Having owned a Roadster for two years, I can say this: Tesla designed Range and Standard mode to avoid the most wearing/damaging (pick one!) thing to an Li-Ion battery-- sitting for a LONG period of time either chock full or very empty-- especially when hot. A Tesla battery, ANY Tesla battery, even the 40 kWh Model S battery, is FAR larger than needed for the vast majority of routine driving by most people. So one only really needs to use Range Mode for relatively infrequent road trips, and when one does, one begins discharging or re-charging the battery very quickly after achieving a full charge or reaching a low charge. So in this scenario the "wear/damage" is minimized because it is the TIME spent at these levels that has the effect. I have done 1,000's of miles of road trips in our Roadster, using dozen of range mode cycles over two years, and total wear on the battery (from ALL activities, including shelf life) is barely detectable-- maybe 1-2% of capacity.
So by encouraging people to use Standard Mode for the VAST majority of routine driving, battery life is maximized while putting only the tiniest burden on the user to pay attention to the need at hand. If people were allowed/encouraged to use the full capacity of the battery routinely, by charging to the gills every night, they would be letting the car sit there for a cumulative thousands of hours cooking its chemistry for no good reason at all!
First time Model S buyers, be very grateful to the the brave pioneers before you who have accumulated over 25 MILLION miles of experience, with an astonishingly few problems! And also be grateful that your battery is not sized to be used to the max constantly, like all of the current competition!�
Jul 13, 2012
VolkerP Prospective Model S buyer here. I am grateful to all roadster owners as their voyages provided invaluable feedback to Tesla in all aspects of being a car company. Thumbs up!
But the part with "not charging to full every time" was figured out well before production start. From the white paper linked in the Roadster battery blog entry from 2007, I did some calculations on capacity, voltage and amps, and arrived at the conclusion that Tesla restricted the operation window a fair bit.
The competition mostly uses other cell chemistry which might or might not tolerate sitting at high SOC in the long term. There are no indications of that, except the Nissan LEAF in AZ, TX, and other hot climate losing "bars" above the expected rate.�
Jul 13, 2012
dsm363 You're correct. A full range charge isn't even a 'full' charge. I believe Tesla keeps a small amount of room at the top of each cell that it doesn't let you touch. That said, you still don't to charge in range mode daily and let it sit at a full range charge.�
Jul 13, 2012
WarpedOne Remember the battery is not like a bottle that has an exact volume or capacity. A battery is more like a baloon that could be filled at higer and higer pressures (voltage) until it suddenly bursts (thermal runaway and a dead cell).
Regular charging to high voltage (high internal pressure) causes more damage than regular charging to lower voltage (lower internal pressure). "Rated cell capacity" is more statistics and accounting than exact science.
"Tesla keeps a small amount of room at the top of each cell that it doesn't let you touch. " only means Tesla is more conservative than producer's specs are. By doing this it can warrant longer battery life.�
Jul 13, 2012
gg_got_a_tesla That's a first! Our own TEG is being quoted in forum signatures now?!
�
Sep 30, 2012
vbsdan FWIW today I charged my Model S in range mode then drove until the range was down to two miles. The trip meter in the car indicated that I had used 77.4 kwh. 77.4/85 = 91%. Still don't know for sure if there is any reserve when the range gets to zero.�
Sep 30, 2012
Lloyd How many miles did you go? Conditions?�
Sep 30, 2012
vbsdan 240 miles, mostly two lane and city, some interstate. Probably averaged 60 - 65 on the back roads, 75 on the interstate. A/C on most of the time.�
Sep 30, 2012
Brian H Interesting! 240/91% = 264�
Oct 1, 2012
mknox One of the magazine articles I read talked about the driver calling Tesla and asking "what happens when the range gets to zero". The answer from Tesla was "the car stops". Haven't heard of anyone actually testing this out...�
Oct 4, 2012
VolkerP From vbsdan's description I understand the car was 100% full and driven down to 2 miles left. Tesla made it clear that at "0 miles left" the car stops. We won't know if that is true (and the remaining charge is reserved to prevent from "bricking" for 20 days) until someone tries it out. :scared:�
Oct 5, 2012
dmetcalf I did a range test two days ago. Went 202 mi with 9 projected and 13 rated showing when I stopped. Used 75kWh. I initially had 302 rated at the beginning, but the roads to Orlando have a much faster average ate of travel and I probably ran 75mph for 80% of the time and 50-60 the rest of the time- very little low-speed driving and probably only 4 stoplights, 3 guard booths and 6 stop signs- not much regen braking. Not sure about the winds, but it was minimal.
Note- my ranges all changed (rated down by 12 miles) last night after a SW update over the air. Anyone have any info on this update?�
Oct 5, 2012
dsm363 It's talked about here
Model S Software/Firmware Updates
They decided (good move I think too) to use the new EPA 5 cycle number of 265 miles as a full range charge instead of 300 so that's why there was the drop. Same range of course just the number is a little more realistic and now much easier to beat than the 300 was.�
Oct 6, 2012
Cottonwood The missing 6 kWh...
I drove my Model S (VIN#S...37) from my house in Boulder to my house in Pagosa Springs, 295 miles. I knew this would be a stretch, especially because there is a net gain in elevation from 5,300 ft to 7,900 ft. In addition, the route passes over a lot of ups and downs, including Kenosha Pass (9,997'), Poncha Pass (9,010'), and Wolf Creek Pass (10,856'). Going into regen on the downs is a great energy recovery, but you get at best, 80% return on what was expended going up; its just lossy to take power out of the battery, convert Voltage and current, run it through the wires, generate it back, convert again and put it back.
Given all of that, I did a rough calculation that I would loose 5 kWh in the net climb, and decided that I would get the cell phone ready, make a lot of calls, listen to the XM and be patient doing the drive at 45 mph to have a chance... Even with 30 mph headwinds in some spots over Wolf Creek, I should have made it. See the picture below. I reset trip meter A just before departure from Boulder after a full, max charge that morning. 295.1 miles, 79.1 kWh, and 268 Wh/mi should be within the capability of an 85 kWh battery, but it was not!
In Del Norte, I has 65 miles to go over Wolf Creek, into headwinds, with a rated range of 50 miles in the battery. That was too close for comfort, and I decided to add a few miles to the battery before going over the pass. I found a great little RV Park in Del Norte, Woods & River RV Park, with very friendly owners. I tried to pay them for the hookup at a 50A outlet, but they refused to take my money and said that they just wanted help me out! Look closely and you will see my Model S charging.
It took 1:45 at the 14-50 outlet to get 45 miles of charge (their Voltage was a little low at 229V, 9kW). With 95 rated miles in the battery and 65 miles to go, I took off over the pass, still going 45 mph. As I went over the pass, I looked down and I had 46 rated miles in the battery; that would have been -4 miles had I not topped off in Del Norte.I had 51 rated miles (+1) as I passed the first friend's house in Pagosa, and 39 rated miles (-11) when I arrived to my house. Had I only put in 15 miles in Del Norte in 30 minutes or so, I would have made it, but having a little extra made me feel good driving after dark in the Rockies. Besides, the dog and I got to do a nice walk by the Rio Grande, then into town to buy a beer, and finally to drink the beer on the picnic table in the RV park as I did some e-mail.
The mystery of the missing kWh is something that we need to figure out or Tesla needs to answer. From the trip meter, I should have had 5.9 kWh left after the drive without a charge along the way. The new SW seems to use about 307 Wh/mi for rated range, so that should have been 19 miles left. In reality, I had -11 miles at the end. 30 miles at 307 Wh/mi is 9.2 kWh; is this really a missing 9 kWh?
Is this missing capacity, a hidden reserve, or is the accounting wrong, maybe counting regen wrong? Are all the power uses (A/C, heat, headlights...) included in the accounting or not? I ran the heat for 20 or so miles at the start, when I realized that I better turn off the environmental drain. Later, as it warmed up, I used the fan to draw in fresh air, but never used the A/C. To keep the efficiency up, I had the windows up all the time, and used friction brakes as little as possible. With this 6-9 kWh is way more than I could have used in environmental and other uses.
Here are a few more inconsistant numbers. A normal charge this morning gave me 243 rated miles; 243/0.85=285, which is more than the 265 EPA number or the 268 I had after a max charge yesterday. 243/268 is 90.7%. Maybe the standard charge is 90% of max in the new SW.�
Oct 6, 2012
dsm363 I think a standard charge is 90% of the new 265 range charge based off of the EPA rating. That's a tough trip to make arp stopping was a good idea. We know they reserve some capacity as you can run your car to empty and still have a month or two I think to plug in although they recommend immediately of course.�
Oct 14, 2012
napabill So, to summarize, do I undersand that a "Range" charge should give you 265 miles, and a "Standard" charge 239 miles? And that use is assumed to be EPA Level 5?�
Oct 14, 2012
cinergi 265 / 240 yes.�
Oct 15, 2012
Cottonwood +/- I have seen 268 right after a max charge and 243 after a standard. Haven't waited on the max, but the standard will droop down to 238 after a couple of days.
SW 1.13.16�
Oct 15, 2012
napabill How does this look for planning purposes? Corrected schedule...
View attachment 10703�
Oct 15, 2012
ahimberg With the 85kWh, only 83kWh is reachable though? (was looking at the EPA site the other day and it listed model S as 83)�
Oct 15, 2012
napabill Column that says kWh added, should be Miles added.
Clarification on Charge Rates:
SC derived using 45 minutes to get standard charge of 239 miles
15-40 derived using 30 miles added per hour
Inefficiency factor - otherwise know as fudge factor.�
Oct 15, 2012
cinergi Yeah, quoting the official numbers. I get 274 rated on a range charge.�
Oct 15, 2012
Cottonwood Good Start!
I think that your spreadsheet is optimistic and may have a few errors. Here are some questions and comments:
- You state charge rate has units of hours. Hours to do what?
- I think that you mean a 14-50 (not a 15-40) connector that can source 40 Amps.
- Your Supercharger numbers are optimistic. See Supercharger - Tesla Motors Club Wiki. It looks like the fast rate for an 85kWh battery is 30 minutes empty to half full, then tapering off from there, getting much slower the last 10% of charge to Range capacity.
- When possible, (starting in Napa, or after the overnight in Blythe) why not charge to the full range mode? On a trip, it never hurts to have a few more miles in the bank.
- Remember Rated Miles can go away quickly with fast or spirited driving, or driving over high passes.
Good luck continuing your planning!�
Oct 16, 2012
napabill You state charge rate has units of hours. Hours to do what? - modified to miles per hour of charge
I think that you mean a 14-50 (not a 15-40) connector that can source 40 Amps. - corrected
Your Supercharger numbers are optimistic. See Supercharger - Tesla Motors Club Wiki. It looks like the fast rate for an 85kWh battery is 30 minutes empty to half full, then tapering off from there, getting much slower the last 10% of charge to Range capacity. - will modify once real-world SC numbers start coming in.
When possible, (starting in Napa, or after the overnight.
Remember Rated Miles can go away quickly with fast or spirited driving, or driving over high passes. - understand, and will likely do that.
Thanks for your comments.�
Oct 28, 2012
mdh Curious... what kind of range are people seeing in the "standard" mode in the Bay Area (Silicon Valley), California? Mostly freeway driving. 65MPH type of thing.
thanks in advance,�
Oct 29, 2012
Andrew Wolfe I'd like to hear as well.
I am an experience electric car driver and have been driving in a quite restrained manner. I'm seeing about 350 W/mi which works out to a full-charge range around 225. Unlike my prior electric cars - low speed stop and start driving does not seem any better. I expected about 20% better than that.
- - - Updated - - -
But these are ideal miles - right? What kind of real mileage are you seeing?�
Oct 29, 2012
cinergi Yes ideal miles (Model S terminology is "rated range"). My Project Range (and observed) on the highway at 65 MPH is 240 (after range mode charge). I'm finding city/secondary driving to consume more power because the car is relatively heavy. The Roadster fared MUCH better in secondary/city driving.
- - - Updated - - -
You need 310 Wh/mile to achieve rated range.�
Oct 29, 2012
Cottonwood Actually, I think it is closer to 308 Wh/mi.�
Oct 30, 2012
cinergi Yeah somewhere around 309-311 ... based on watching my WHPM and observing when projected and rated match each other. They do when it's 309-311.�
Oct 30, 2012
roblab I have found that driving the 100 miles to Fremont, if I set cruise at 60 mph and use Low Regen (which is simply less aggressive so less abrupt doing freeway cruise). I can run at 285 wh/mi, or 300 miles per charge. I have not driven at 65, so I can't tell you how that works. 60 is right lane, same speed as trucks, no hassle, no problems, and the rest of you can pass me. Of course, you'll take more time recharging. I also got close to 300 miles per charge going to Reno and back from Napa Valley. At 60 mph on low regen cruise. With air on. I don't understand the drama that one of the car mags had going to Las Vegas. Is it uphill from LA?�
Oct 30, 2012
spatterso911 Yes. You must travel through the high desert (Victorville is around 3000 ft elevation).�
Oct 30, 2012
mdh Great! I assume this was on range mode�
Oct 30, 2012
napabill roblab: Not clear on why you think "low regen cruise" enhances mileage? Did you use Folsom for the ride to Reno? There are two of us here down-valley at Silverado that have S's coming late November/December. Can't wait.�
Oct 31, 2012
jerry33 My guess would be that it throws less energy away as heat (Regeneration takes the kinetic energy and converts it into electricity and heat. Heat does not add to range.). Cruise typically accelerates and brakes too hard in the process of keeping the speed at the setting so the lower regen setting may overcome some of the tendency for cruise to throw away energy. We need some independent verification here, sadly, I'm still "reserved" rather than "finalized".�
Oct 31, 2012
efusco On a flat or continuous uphill drive the regen setting would be irrelevant. But in the real world there are uphill and downhill segments. On any downhill segment steep enough that cruise is not inducing power to the wheels the most efficient mode would be a free wheel coast. Because regen is not 100% efficient any energy recaptured is, by definition, less than the kinetic energy than was present. Simple conservation of momentum.
So, when highway cruising, the less 'off the accelerator' regen the better. Now, how measurable that will be probably depends a lot upon the particular road driven (steeper more frequent hills would seem the obvious to show benefit from lower regen). Even then the amount may not be terribly significant.
Evan, Via Tapatalk�
Oct 31, 2012
arg You are probably right in practice, but the calculation is not as simple as that:
The energy here is coming from the potential energy change from higher to lower on the slope. The excess above that needed to keep the car going at the commanded 60mph can either be stored as excess kinetic energy (car going faster than commanded), or stored through regen in the battery - in both cases, then liberated from that storage when the slope decreases and the potential energy change isn't sufficient to sustain the forward speed. In the regen case, energy is lost through inefficiencies in the charge/discharge/motor process. In the excess speed case, energy is lost (compared to going at constant speed) because the drag increases proportional to at least the square of the speed. So it's not immediately obvious which is more efficient.
Consider a very long continuous slope where the terminal velocity (freewheeling) was 80mph. If you freewheeled down it, all you've got at the bottom is that you are doing 80: the deceleration from 60 to 80 on flat ground won't buy you very much range, wheras if the slope was very long you could have a significant amount of range saved up in the battery through regen. Conversely, a very stiff cruise control maintaining exactly 60.00 mph on an undulating slope where the freewheel wouldn't have gone much above 60 in the first place is almost certainly wasting power.�
Nov 6, 2012
Cottonwood Hear, hear! This is absolutely correct in practice. Living in Colorado, I get to experience long mountain up and downs and small rollers in the plains. On long mountain descents, you end up with way more energy in the battery regenning down. Its still a net loss from flat driving because of inefficiencies in the regen process, but better than no regen. In the rollers, short periods at higher speed have less loss to aerodynamic drag than the regen losses, so its better to freewheel, but once again worse than flat ground.
BTW, one other advantage to high altitude driving is that the thinner high altitude air offers less aerodynamic drag than thick sea level air. An electric car has no loss of power at altitude, but does lose cooling capacity.�
Nov 6, 2012
wycolo > Cruise typically accelerates and brakes too hard in the process of keeping the speed at the setting so the lower regen setting may overcome some of the tendency for cruise to throw away energy. [jerry33]
Substitute 'regens' for 'brakes', no? If you have ever cruised in a Roadster this would not likely be your takeaway, IMO, since its style of Cruise is totally seamless- a thing of beauty. The Amps in/out gauge is not swinging back & forth at all. There is no slop. This absolute consistency must payoff in the long run to give better economy than one's right foot. It is certainly more relaxing than the alternative of second guessing the parameters involved with every hill or turn. I know, others have expressed their being able to 'beat their cruise' but that is probably due to the crudities & peculiarities of their particular cruise. The Roadster Cruise should be technically analyzed if it has not been already. Also too, it is altitude immune.
--�
Nov 7, 2012
roblab Hi, folks.
As to light regen, it is mostly less aggressive. It cuts in slower, goes out slower, so less abrupt. If it is able to keep you at the preset speed (and it is in almost every case, especially at freeway speeds), then high or low regen are the same as to saving power otherwise lost.
The talk about "freewheeling" is just what the car does when it is not putting power in or doing regen. The power gauge is on zero. You are freewheeling, just like in neutral on a car with a tranny.
After driving to Canada, with LOTS of mountainous roads and VERY cool temps, I felt that a lot of loss was due to the heat exchanger (climate control) Wish I knew exactly what heats the front window for defrost. Going up and down over and over lowers your range.
I did not necessarily charge in range mode before going to Fremont. I said I used 285 Wh/mi, which would give you 300 miles on a full charge, in range mode. When I went over the hill to Reno, over 7000' at the summit, I had charged to full in Rocklin (Sacramento) before going. I got 300 miles per charge, but it was 4 charges, with an average usage of about 285 Wh/mi, which is 300 miles per charge. I would never attempt to stretch it from full to empty hoping to get to another charger.
You in Napa would be 25 to 30 miles closer than me. The only problem is going up the hill and having your projected range drop so far that you can't make it over. Once over, you recoup a bunch of charge coming down into Reno.
And remember, I was doing 60, not 70 or 80, and my climate control use was minimal. In the winter or summer it would have been worse.
I plan to go over again in about a month. We will see how it makes it in less than ideal conditions.
- - - Updated - - -
One more real world comment. I find that cruise is MUCH better at keeping the car going smoothly. With my foot driving, the energy gauge looks like Tesla Stock. With cruise, it looks like gentle ripples on a lake. Driving with foot, I get closer to 310 - 350 Wh/mi. Cruise gets me down to 285. Slow and steady win the race. (Now where have I heard that before??)�
Feb 5, 2013
widodh So after checking various posts here and screenshots the available capacity of the 85kWh pack seems to be 75 ~ 78kWh in range mode, the rest is not usable to protect the battery from being fully drained?
I'm still calculating that I'll be doing an average of 230Wh/km on highway speeds (120km/h / 75mph)), so that would give me a range of somewhere about 330km (206m).
I saw this today in the Roadster as well, doing 122km/h on the cruise control, with:
* AC on (prevent fogging)
* Heater slightly on (4 degrees Celsius)
* Seat heater on
* Wet road
* Some wind
* Winter tires
That gave me an average of 230Wh/km and since Model S is heavier and bigger that's what I'm thinking about.
That brings me to:
Pack: 85kWh
Range: 78kWh
Standard: 68kWh
P.S.: We should REALLY have a Wiki about this when this is sorted. This is information people want to have to do their own math.�
Feb 6, 2013
mnx I've seen posted many times that the usable portion of the 85kWh battery is 81.5kWh.
Here is one such post: Lifetime Average Wh/mi - Page 2
�
Feb 9, 2013
agentsmith1612 Hello, I am new here in the forum.
And I want to know what they have done exactly for the range mode in the model S.
If you put the car into range mode and charge it, the upper SOC increases to an higher level ?
Then if you drive in the range mode the bottom SOC is lower ?
All in all the SOC Level on the top and at the bottom go to a little higher/lower values ?
Is that the right explanation ?
And are there any factors in range mode that will reduce, like the cooling or heating for battery or the engine power ?
Imagine you plan a long trip and take the car in the evening into range mode and plug it in, is there morge "damage" for the battery to be the whole night into range mode (and fully charged) as in standard mode (not so full charged) ?
Last but not least, for the Roadster I have read that there are owners that plug the Roadster in at the evening but the "charging plan" is programmed in this way that the charging ends up 30 min before the owners get to work in the morning of the next day, because they assume a longer life time of the battery to be not so high charged at night (this owners always use standard mode).
Are the any charging issues for example thze balancing of the cells ? I read in the internet for the roadster that if you take range mode for charging, you have to be sure that the next charge is in stadard mode and you have enough time, because of balancing the cells.�
Feb 9, 2013
brianman @agentsmith - There are two types of "range mode" on the Model S: range charging mode and range driving mode.
Charging mode affects how much of the battery capacity will be replenished when charging.
Range charging mode charges to 100% of capacity, while standard charging mode charges to 90% capacity.
Driving mode affects consumption of battery capacity while driving.
Range driving mode is described briefly in the Release Notes:
Model S software/firmware changelog - Tesla Motors Club - Enthusiasts & Owners Forum�
Feb 10, 2013
agentsmith1612 But the range driving mode has no effect of battery cooling/heating or the battery life time?
How much range you can get from driving range mode more ?
and how much more from charging range mode ?�
Feb 10, 2013
jerry33 Shouldn't. If anything it will improve battery life because the battery is stressed less.
That is a real how long is a piece of string question. It depends on many factors such as ambient temperature, speed, wind, terrain, driving style, etc.
Range charging mode adds 10% to the capacity. There is a very good write up here.�
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