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Thoughts on Battery Packs, Sizes, Packaging

Thoughts on Battery Packs, Sizes, Packaging

Hello everyone,

My name is Marco. This is my first post on the forums and I am a first time Tesla user since reserving Model 3. A little history about myself, I'm an Aerospace Engineer that specializes in fluid dynamics and aerodynamics of aircraft/spacecraft. This does not give me any special powers of predicting the physical possibilities of the Model 3, but I am here to constructively analyze the Model 3, speculatively of course. I wish I could do it qualitively but unfortunately I do not work at Tesla. (Note to Tesla, if you are hiring any Aerodynamicists, let me know haha)

So like many, I've been giving a lot of thought about the Model 3. I have driven a handful of Model S, and I currently lease a Gen 2 Volt. After listening in to the Q1 Earnings call, I have a lot of confidence in Tesla. However, I'm now dissecting the battery options. What we know is the base Model 3 will have a battery pack less than 60kwH in size. This will deliver an EPA (not Tesla rated), 215 miles (or more) per charge. I think with the CD being closer to .21, and some weight shedding, the Model 3 could approach ~235 miles EPA. With that, I expect real world driving range around 190 miles per charge. This is also for a strictly real wheel drive powertrain and one motor.

Now we know we'll see Dual Motor options, and with Mr. Musk's confirmation of performance models, we know larger battery packs are essential. Let's say a 55kwH battery is base. The battery pack is going to be much simpler and smaller than the Model S. They physically cannot fit the Model S/X battery platforms because the dimensions are too large for the Model 3 wheelbase. This is where I get a little worried about battery sizes. I believe Tesla will offer 3 versions of the Model 3, like Model S. The base car, the largest battery pack for maximum range (dual motor), and then a performance Model 3 with the same battery as the max range model, but with a larger rear motor to deliver more acceleration. What could the sizes be? I'm not really certain. It all depends on the chemistry of the battery. Energy density is increasing. I think a good indicator is Model S. If we see a 95D, 100D, etc in the next year or so, we know that density is increasing with the same dimensions.

My honest guess?
55kwH base = 230-240 miles
70kwH D = 290 max range (could be above 300 if CD is .21, and driving the speed limit)
P70D = 270 miles max performance

Though this is just one persons opinion. I invite you to critique, offer your own 2 cents, and begin a conversation. I believe it would be epic for Tesla to have a 300+ mile Model 3. Though its doubtful, not because of it beating it's Model S brother, but mainly for manufacturing simplicity. Making 2 battery packs for the first few years is much easier than making 3 over that span of time. 2 lines vs 3 lines.

Looking forward to your responses, and I apologize in advance if there are any typos, writing this on my phone.

PeterPlt | 26. Mai 2016

Let the speculation continue...

I expect the M3 to be offered with two battery options: min and max (hopefully >300 sm range).
The drive train will be offered in two options: RWD and AWD.
The motor power will have at least two options: Standard (0-60 mph<6.0 seconds) and Maximum Plaid

I'm going for option 2 on all counts! Woo woo!

Marcohanna94 | 26. Mai 2016

I think RWD will only be on the base battery pack. Rest is Dual Motor.

Red Sage ca us | 26. Mai 2016

Marcohanna94: +1! Great first post. Welcome. I hope that your future contributions are as well stated.

I personally hope that the reports of a 'less than 60 kWh' battery pack for Model ☰ are incorrect. I would prefer that the battery pack capacities be either 60 kWh and 90 kWh to start, or 70 kWh and 100 kWh. I would hope that would allow for an EPA rated range of anywhere from 225-to-250 miles on the low end... To 320-to-370 miles on the high end. It seems that most Tesla Enthusiasts are expecting the range to be in the 220-to-270 mile spread at best. And those who speak of 'Real World' range will truncate even that to only 70% the distance, or less than 200 miles.

It does all depend upon overall efficiency of the car. If it can achieve between 190 Wh per mile and 225 Wh per mile during testing the battery packs will not need to be very high capacity at all. But if it instead hovers between 270 Wh per mile and 330 Wh per mile, you'll need all the capacity you can get.

60 kWh Capacity
Wh/mile _ Range
190 _____ 256-300
225 _____ 216-253
270 _____ 180-211
330 _____ 147-172

PhillyGal | 26. Mai 2016

Reading is fundamental. I was about to refute your saying that we "know" the Model 3 will come with a 60 kwh battery pack but re-read that you correctly said "less."

Very nice post and welcome to the forum!
My guess agrees with your guess that RWD will only be on the base with the rest being dual.

Marcohanna94 | 26. Mai 2016

Red Sage ca us:
Thank you for the compliments on the post!
Unfortunately, I believe the base model will have something less than 60 kWH. Reason being, Tesla no longer buys the 60 kWH from Panasonic, they only buy 75 and 90. Also, even if they began purchasing the 60 kWH pack, it wouldn't work. The 3 platform is shorter and not quite as wide. A few inches here, but the Model S platform literally packs cells to the edges of the subframe. It's quite excellent packaging in my opinion. Also, to keep cost down, I highly doubt other shapes of battery packs other than the one we saw during the unveiling. Rectangular, flat pack that carries fewer cells than the Model S. I completely expect to see a 55 kWH entry and a 75 kWH (or 80) for the D and P models. Anything higher than that will have to come from extreme advances in energy density.

Take the 90D. We know the battery has a usable capacity of 90 kWH. It weighs about 540 kg, therefore it's density inside the cells is 6 kg / 1 kWh, or .167 kWH per kg. Model 3 will perhaps have something closer to a 430 kg battery cell. In order to have the same energy, it would need something around .2-ish kWH per kg. Not impossible, but expensive. If we kept the same density numbers, a 430 kg pack would be roughly 70 kWH. I say, they'll increase density a bit to get 75 kWH of usable energy in the upgraded model.

Again, this isn't solid, just theory and a little predicting.

Marcohanna94 | 26. Mai 2016

PhillyGal:
Very, very fundamental :)
Thanks for the good vibes!

Red Sage ca us | 26. Mai 2016

Marcohanna94: Tesla Motors has always built their own battery packs. They are of an internal, proprietary design. What they bought from Panasonic was 18650 battery cells, which are used to fill those battery packs. 18650 is a particular format for a battery cell, that is roughly 18mm diameter by 65mm tall. These battery cells are also a specific formulation and design that Tesla Motors chose for use in their battery packs. This design does not include the fuse/circuitry that commercial battery cells do, because the battery management system for the battery pack itself controls the charging and discharge of those battery cells.

TeslaTap.com | 26. Mai 2016

@Marcohanna94 - Interesting analysis! I believe JB confirmed the base pack is less than 60 kW last month (in refuting a cost analysis by GM). 55kW is reasonable, but perhaps as small as 50kW. Tesla needs to make this pack as economical as possible to meet the $35K price target. Not sure why some want a larger base battery, it really doesn't matter if the battery is even $30kW (not likely), so long as they meet the range and power objectives.

Tesla never purchased any packs from Panasonic, only cells that Tesla assembled into the various pack sizes. As far as I know Panasonic is still the only supplier of cells, all coming from Japan. The GF should come on line later this year and may provide some portion of the cells in the S/X and then the 3.

From the x-ray pictures from the M3 revel, it is clearly a different pack design. It looks to have room for 8 modules, which are differently sized from the modules in the S/X. In the S, the different pack sizes use different number of modules and pack the batteries different within each module (see my undocumented section if you need more details at http://teslatap.com/undocumented/

There has been crazy talk of 90-100 kW packs for the 3 in other threads. There is no way this will happen. As the battery capacity increases from the base, the space needed increases, the weight increases, the entire car design needs strengthening, more crash structure to handle the weight gain, electronics need to handle more power, and other details that drive the entire base car cost higher and higher. The #1 objective is to make the 215+ mile range EV for $35K. Anything that gets in the way of that is going to be discarded. I do think there will be a larger pack, but unlikely to be more than 70-75 kW. For more range and power, Tesla will be happy to sell you a Model S or X!

Marcohanna94 | 26. Mai 2016

@ RED
My apologies, that's what I meant, they buy the cells. However, they will still need more dense cells to make achieve a high rating, which is why 55 and 70-75 kWH packs are most likely.

Marcohanna94 | 26. Mai 2016

@TeslaTap completely agree. However, take the 85 and 90. Or 70-75. Roughly the same weight and dimensions, just denser cells. For the 8 modules in the pack, I can see a less dense pack at 55 and the larger pack at 70-75. Weight will be the primary limiter to range. CD will add/shave 5-10 miles.

Red Sage ca us | 26. Mai 2016

Marcohanna94: Please stop by YouTube and check out some videos of Tesla Motors' Chief Technology Officer, JB Straubel. He covers the details about their battery technology within them.

ShJuKTmtHjY -- JB Straubel | Energy@Stanford & SLAC 2013 (30:45)

CwogwK66EWE -- JB Straubel & Ira Ehrenpreis | The Tesla Story (56:47)

bd2Oqh6X-V0 -- Tesla model 3 Tesla Motors JB Straubel (59:07)

4hNdbGjZfFU -- JB STRAUBEL ON HOW TO SPEED INNOVATION LIKE TESLA - CO-OP THINK (52:00)

Red Sage ca us | 26. Mai 2016

TeslaTap wrote, "I believe JB confirmed the base pack is less than 60 kW last month (in refuting a cost analysis by GM)."

Could you please point me to a source for this? I typically only believe JB Straubel or Elon Musk. I have only seen people pointing to a communications/marketing officer or something that stated 'less than 60 kWh'. I've not seen any confirmation of that officially from Tesla Motors or JB or Elon. All Elon said was that the average capacity would be 'less than 75' kWh. That falls into the ranges I speak of, being 60 kWh and 90 kWh or 70 kWh and 100 kWh.

So if you have seen something that literally confirms 'less than 60 kWh', please let me know, so I can stop biting people's heads off... :-D

Drdpharris | 26. Mai 2016

This article by Randy Carlson: http://seekingalpha com/article/3975416-tesla-model-3-wins-innovative-simplicity?source=all_articles_title discusses his theory that the Model # battery modules may be air-cooled by a central conditioning unit. "The battery pack and module configuration shown by Tesla at the Model 3 unveiling is consistent with the previously predicted battery size if circulated air rather than coolant is used within the battery modules to cool the cells."

Drdpharris | 26. Mai 2016

@Red Sage ca us -- IT is mentioned in this article: http://www.streetinsider com/Analyst+Comments/UBS+Sees+Telsas+%28TSLA%29+Model+3+As+Unprofitable/11540932.html

"Tesla disagrees with Bereisa on battery and Model 3 costs. Jeff Evanson, head of TSLA's IR, dialled into the call during Q&A to contradict some of Jon's statements. There were two main points of contention:

1) Jeff stated that the Model 3 will only be partially aluminum, not all-aluminum

2) Jeff stated that the Model S's all-in pack cost today is already <$190/kWh and that the Model 3 will have a battery size below Jon's estimate of 60kWh."

Red Sage ca us | 26. Mai 2016

Marcohanna94 wrote, "My apologies, that's what I meant, they buy the cells. However, they will still need more dense cells to make achieve a high rating, which is why 55 and 70-75 kWH packs are most likely."

The videos I directed you to for JB Straubel are the basis for my presumption that Generation III vehicles will have battery cells with much better energy density than those used in 2012 for Generation II cars. JB saw about at 40% improvement from the 2007 introduction of Tesla Roadster to the 2012 release of Model S. I would hope to see a similar improvement considering the 2017 release of Model ☰. Even if the improvement were only 30%, that would mean the volume that held 60 kWh in 2012 would be able to hold 85 kWh in 2017. Naturally, if it were a 40% improvement, you could hold 100 kWh in the space that would have held 60 kWH in 2012. Also, the wheelbase for Model ☰ appears to be longer than its contemporaries, perhaps 113"-to-114" or so, plenty of room for a roomy skateboard. This is why I am so confident that Model ☰ may still reach, and potentially exceed, a 100 kWh capacity.

Red Sage ca us | 26. Mai 2016

Drdpharris: Yeah. Jeff Evanson is not Elon Musk or JB Straubel. I do my best to avoid clicking links to [SINKING ANCHOR], and StreetInsider, among others. I do not consider them trusted sources.

TeslaTap wrote, "There has been crazy talk of 90-100 kW packs for the 3 in other threads. There is no way this will happen."

Sure it can. If there is a 30% improvement in energy density between the 18650 battery cells used in 2012, and whatever battery cell configuration that is used in 2017, that means a 60 kWh capacity could be reached in the same volume that previously would have held only 42 kWh. If the improvement is 40%, then 60 kWh could be held in the volume that previously would have held only 36 kWh. Also at 40%, the volume that would have held 60 kWh in 2012 could hold 100 kWh in 2017.

Marcohanna94 wrote, "Take the 90D. We know the battery has a usable capacity of 90 kWH."

Sorry, I missed this before... No, we don't know that. There is a portion of the battery pack that is held in reserve. Most refer to this as 'anti-bricking' or 'protection' space. The exact amount that is held back may vary from one capacity of battery pack to the next and is determined internally by Tesla Motors. I typically presume that around 10% of each battery cell is always empty, though some presume it may be as small as 5%. I also figure that EPA testing seems to achieve around 90% the range that someone might otherwise expect to be possible. With that in mind, I do range calculations as if a 90 kWh capacity only has ~72.9 kWh of usable charging space. That is probably a low estimate, but definitely keeps the results within the realm of possibility.

This is why I believe that Model ☰ should have no less than a 60 kWh battery pack capacity. It will have to be extremely efficient to make the stated range of 215 miles or more using a 55 kWh or 50 kWh battery pack. That is certainly possible, but perhaps not with the expected Performance parameters.

60.0 ___ 54.0 ___ 48.6 ___ 226 Wh/mile
55.0 ___ 49.5 ___ 44.6 ___ 207 Wh/mile
50.0 ___ 45.0 ___ 40.5 ___ 188 Wh/mile

Drdpharris | 26. Mai 2016

@Red Sage us ca --- Yes, lots of doubtful stuff. However, this was a report from a conversation with Tesla’s Vice-President of Investor Relations, Jeff Evanson, and it has been repeated http://electrek.co/2016/04/26/tesla-model-3-battery-pack-cost-kwh/

Marcohanna94 | 26. Mai 2016

@RED
Well, yes. There is definitely some speculation in my analysis. Though, I think TeslaTap hit the nail on the head about ease of manufacturing. I really think they are going to downscale and focus on the little things that add up to good range. Adding a more dense and larger battery adds weight and you start meeting the law of diminishing return.

The base will be small. Less than or equal to 60 kWH small. And there will probably be one upgraded battery, but I just don't see technology advancing that quickly between now and final design off. Remember, any production is signed off on well before the scheduled date of actual production. In Tesla's Q1 call he mentioned the final engineering sign off was 6-8 weeks from the from the first week of May. That's end of June which is a month away.

Any changes made after that will be extremely difficult and super costly because after the sign off, their suppliers are going to begin producing the parts. Again, Tesla's aim is not to make a 300 mile ranged super electric vehicle. Their aim is to make 100K Model 3s with at least 215 miles of range in 2017, and make 500K Tesla vehicles in 2018, with about 350-400K of them being Model 3. Complexity - Model X 18 month delay.

Trust me, I would love a 300 mile Model 3. I really wish they would make it, but I have a very hard time believing it's going to happen. I honestly think, from an engineering perspective, the final design and components are going to be final next month. Which means, Tesla is not going to bet that new battery technologies are going to advance that much between now and launch. That is why they said 215 miles per charge (that's what possible now) with the battery size on the base model. "Hope to exceed them" means, between the debut and final sign off, they may be able to increase range with a few minor tweaks... But not a major redesign of the battery.

I don't mean to sound like I'm raining on anyone. I am just attempting to keep my sensible hat on.

Marcohanna94 | 26. Mai 2016

The most probable is a 55 kWH and a 70-75 kWH. Anything more will be a welcome surprise. They may even have a 65kWH instead of the 70-75. Anything above that is going to be crazy to make possible given the time and resources.

Red Sage ca us | 26. Mai 2016

Drdpharris: It's just that I am reminded of 'a Tesla Spokesperson' who remained unnamed who was quoted/paraphrased as saying the Model X would have a towing capacity of 'almost 10,000 lbs' by similar sources... but the car actually had only a 5,000 lbs towing capacity upon its release. So, just in case things are wrong, I prefer them to be firmly wrong from the horse's mouth, rather than a paraphrase of an overheard conversation.

Even with a rather minimal buffer for reserve/protection, the Model ☰ will have to be incredibly efficient in practice when using smaller battery packs:

100% __ 95.0% _ 90.3%
60.0 ___ 57.0 ___ 51.3 ___ 239 Wh/mile
55.0 ___ 52.3 ___ 49.6 ___ 231 Wh/mile
50.0 ___ 47.5 ___ 45.1 ___ 210 Wh/mile

I believe most Model S drivers claim between 280 Wh/mile and 330 Wh/mile lifetime averages. Comparatively speaking, being under 240 Wh/mile across the board would be awesome. But I want the Model ☰ to drive like a Tesla, not a Toyota.

Red Sage ca us | 26. Mai 2016

Marcohanna94: OK. It seems that the two of us are 'crossing the streams' here... I know what is thought of as being 'sensible', or pedantic, or pragmatic... I just don't agree with it. I am your Friendly Neighborhood Over-the-Top-Optimistic Tesla Motors Apologist Fanboy, and stuff. I refer to those who prefer more pedestrian prognostications as being members of the League of Lowered Expectations. :-D

That said... I really don't want Tesla Motors to simply have enough capacity to just barely squeak by the 200 mile range mark in official EPA tests. I soundly believe that they must absolutely blow through that mark, even with the base version of the Model ☰, or risk being lambasted by the press. I also believe that if the base Model ☰ does not have 'enough' range, Tesla Motors will find themselves in the same situation as they did with Model S. That is, by being surprised that people purchase the highest capacity battery pack in much greater quantities than they expected.

Over the past four years, the highest capacity battery pack for Model S has been the overwhelming champion in sales for the car by a very wide margin. Should that happen with Model ☰ as well, all anyone will report about is the cost of that version of the car... All the while hinting that Tesla Motors had somehow 'missed' their price target.

So, yeah... 55 kWh and 70 kWh will very likely be the offerings, if all rumors and prognostications by the League of Lowered Expectations are true. I just have much higher hopes for Range and Performance than others do, it seems.

If a 70 kWh battery pack happens to weigh just under 700 lbs... If a 100 kWh battery pack ends up being around 1,000 lbs... I believe the Range and Performance gains would be vastly superior to offering a 55 kWh or smaller battery pack that weighed less than 600 lbs.

My speculation leans toward excellence as the goal. I believe that is what Elon Musk would like when it comes to the term 'compelling'. The Model ☰ should be compelling.

Marcohanna94 | 26. Mai 2016

@RED
Oh, I know. People will pay for it but not everyone will be able to afford the higher range. Model S is a bit different. Mainly because the base model is 70K. To a lot of people spending 70K on a car, the extra 10-15K for the 90 kWH isn't a huge deal. A 5K-10K price increase in Model 3 is a large percentage of the total price of the vehicle and in this market, it won't work.

The thing Mr. Musk has made clear is they have to avoid the processes they had with the S and X. Why? Because it was too complex and ended up running over time, over budget, etc. Model 3 is a completely different approach. They are only putting people who know how to perform and deliver on the project. I.E., not a whole lot of Model X engineers. Model 3 is a complete rethink of manufacturing for them. They have never attempted anything like it. And the ONLY way this is going to happen is if it's more simple to build. Battery being the largest player in that.

Realistically, a 100 kWH battery is more likely in the next model year Model S/X than Model 3. Business wise... Never going to happen. Cannibalizing a higher up model is a huge no-no. What they will do is make the Model 3 the best it can be with the available hardware. That is, hyper efficient wheels, hyper efficient motors, and some clever design and weight shedding. All in the name of efficiency and making the range increase. Large batteries weigh a lot. Smaller batteries don't. Anything that interferes that philosophy will be rejected in the design. In my honest opinion, Model 3 will be a wonderful car. And for everyone who pre-ordered it, they were obviously okay with 215 miles rating. Otherwise, why would they give Tesla their money? Honestly, if the Model 3 had 1/10 the pre-orders, then Tesla would rethink the 215 miles... But having nearly half a million pre-orders says 215 miles just sounded right because Mr. Musk did not mention anything about larger battery packs. He only spoke about faster models. Faster models will need more energy output, therefore, larger batteries. So it's safe to say that Model 3 will have an extended range model with AWD and Performance models. And I think more people will buy those than the base, but I will say a good portion of people will also find the 215 or more miles of rating adequate. Especially with the SC network by 2017-2018.

Drdpharris | 26. Mai 2016

@ Red Sage ca us and Marcohanna94 -- I am with you. Plan for the worst, hope for the best. I am guessing they will make their minimum targets, say 225 mi, but agree that many will want the bigger battery if they can afford it. It would be dumb to not allow for an upgraded battery, and I have seen no evidence these guys are dumb.

Marcohanna94 | 26. Mai 2016

@Drdpharris Agreed.

Red Sage ca us | 26. Mai 2016

Marcohanna94: Oh, there will be no significant cannibalization among Tesla Motors product line siblings. Tesla Generation III is the goal for the company. It isn't some afterthought, or nuisance that they must bear. The company was founded to bring the Model ☰ to market. If demand for Model ☰ grows so high that Tesla is unable to fulfill orders for it without sacrificing Model S and Model X? That is exactly what will be done. Say goodbye to those 1-month lead times in North America for the Model S.

Tesla Motors looks at things differently than other manufacturers. Tesla's high end vehicles exist to allow the creation of their mass market cars. Trust that Mercedes-Benz, AUDI, BMW, and Porsche see things the other way around. Their high selling vehicles are to them a 'necessary evil' that allows them to pay the bills while they build the cars they really want to make instead. If Mercedes-Benz could make just as much money by selling 3,000 of the S-Class per year as they get from CLA-, C-, E-Class vehicles combined? They'd drop the lower priced cars in a hot second.

The Tesla Model S will be too busy continuing to gorge on the smorgasbord buffet by eating sales from AUDI A8, BMW 7-Series, Jaguar XJ, Lexus LS, Maserati Quattroporte, Porsche Panamera, and other 'flagship' vehicles to give one whit about how some may perceive the Model ☰ as 'stealing' it's thunder. And meanwhile, the Tesla Model ☰ will be cannibalizing an entire segment of its own as Acura TLX, AUDI A4, BMW 3-Series, Cadillac ATS, Infiniti Q50, Jaguar XE, Lexus IS, and Mercedes-Benz C-Class sales fall off a cliff into oblivion.

The only sibling rivalry here will be to see how much quickly the Model ☰ will demolish its direct competition. He ain't heavy. He's my Brother. [ YouTube -- Jl5vi9ir49g ]

Tesla Motors moves forward. They create a platform, and they continually improve it. Those who expect the Model S to be a stagnant target should have learned their lesson on October 9, 2014. If anyone expects the Model ☰ to stay two steps behind Model S, they'll learn the error very soon. Because their largest vehicle, the Model X, has a version that does 0-60 MPH in 3.2 seconds. That's half a second quicker than the Tesla Roadster. There is no reason to expect the Performance aspects of Generation II vehicles will be forever superior to those of Generation III vehicles.

"We don't make slow cars." -- Elon Musk

bj | 26. Mai 2016

@Red Sage - "I believe most Model S drivers claim between 280 Wh/mile and 330 Wh/mile lifetime averages" - wow that's not very good IMHO. OK, I drive a Leaf, not a Tesla, but my lifetime average is currently 137 Wh/km which converted to imperial (gag) is 220 Wh/mile. And it's getting better, the battery management software update last year seems to have improved efficiency by about 10%.

I would expect the Model 3 to have similar economy to the Leaf, if not better, since technology has moved on, focus on CD has improved, and Model 3 will only be a bit bigger than the Leaf.

If Model 3 does nothing more than match the efficiency of the Leaf, a 75 kWh battery would deliver me 550km of range or (yuk) about 340 miles.

That assumes I don't spend my entire time trying to accelerate to 100 km/h in 5 seconds.

afestini | 27. Mai 2016

This thread has changed my thinking from "get the biggest battery you can afford" to "get the one that makes sense for you".

For example, I have a daily commute of 45 miles (99% Autobahn). Even if I floor it and crank up the heating, a 55kWh easily gets me there and back again, most likely even twice. Longer distances are extremely rare (125 miles a few times a year).

Obsessing over maximizing range and getting bigger batteries means lugging around more weight, wasting some of that extra capacity to pay for itself (interestingly, batteries in cars seem to be a lot like rocket fuel). Ultimately that means higher consumption and paying more without getting any real world benefit whatsoever.

Non-home chargers (me) would of course benefit from being more relaxed if the usual public chargers are blocked or out of order ("no problem, I'll try it tomorrow, or the day after"), but for many (most?) a huge battery would seem like a complete waste of money and resources.

Unless you have a longer commute, travel a lot or can't charge at home/work, what's the point of a 100kWh battery?

Definitely offer the biggest batteries possible (and some in between) for those who need it, but let's not ditch the small ones. If they can get over 200 miles from a 55 or even just 50kWh battery, why make it more expensive for no reason with a battery many (most?) may never really need?

yongliangzhu68 | 27. Mai 2016

afestini, I agree that we VASTLY overestimate our needs and driving distances. I have been using a device/App called Automatic for a couple of years and it is shocking to map out a year and find that you spend almost every day driving the same small routes. You realize that you don't drive near as far in any given day as you imagine you do. So for the few times a year that you do drive on a trip if would be worth budgeting and extra SC stop or 2 than 'needing' to get the largest pack.

However there is one area that will require the largest battery pack and that is if you want Ludicrous mode.

afestini | 27. Mai 2016

True, driving at top speed and using Ludicrous will suck that battery dry in record time (in one video, going at 200kmh seemed to drain it 3 times faster). Though even at that rate I probably wouldn't need more than half a charge a day.

One factor to keep in mind is that the battery should be kept between around 20-80%, so that's definitely cutting into the range and quickly turns 210 miles into more like 130 miles (realistically 90? No experience with ratios between estimated and real ranges).

Out of curiosity: how many Tesla owners got Ludicrous, used it a few times, showed it off to everyone and then disabled it to save battery? It's a feature I'm glad exists, because it makes a great statement and is just ridi.. ludicrously cool, but it seems a bit excessive for regular everyday use.

bj | 27. Mai 2016

@afestini - yup, even though I've never driven a Tesla (and so probably talking out of my a**) I would put Ludicrous mode in the same bucket as colour changing LED lights. It's a party trick - show it off a few times, then never use it again.

Many years ago when the company I worked for moved to a brand new HQ, they made this huge translucent white wall behind reception that was illuminated with colour changing LEDs. For the first few weeks they had it cycling through all the colours of the rainbow. Well, just because they could. I predicted it wouldn't last. It drove the receptionists nuts. I haven't seen it change colour in the 9 years since.

yongliangzhu68 | 27. Mai 2016

afestini: Ludicrous is not just about draining the battery. It is actually about needed a larger battery to send more current instantly to the motors. Linear increases in acceleration require an exponential about of power. So if Tesla wants the Ludicrous M3 to hit a sub 3 0-60MPH (0-100 kph) it will probably need a 70kWh to 80kWh pack to supply enough instant power regardless of range.

Marcohanna94 | 27. Mai 2016

Ludicrous mode is an actual hardware change. Basically allows small bursts of s lot of energy which requires a lot of amperage (current). The more current going out, the faster the rate of discharge, therefore it's necessary for a larger battery.

Also, people want to remove the thought of range anxiety. In Europe it seems people don't mind it probably due to the close proximity of locations. However, here in the U.S. We don't like each other very much and build far away. Or for some, living is only affordable in a further suburb which requires a longer commute.

TeslaTap.com | 27. Mai 2016

Here's a different perspective on why the base battery will likely be 50-55 kW. The Model S60 was using batteries designed 4 years ago got 208 EPA miles. We expect the Model S is a heavier, larger, with a higher CD and larger frontal area that the Model 3. Going from 208 to 215 only requires a 3% gain. With the newer more efficient batteries AND all these other changes, there is no reason to burden the cost of the Model 3 with a 60 kW pack. It really can be smaller, and perhaps a lot smaller like 50 kW. As the pack size get smaller, it also increases the weight savings, further boosting range while meeting price target goals.

Marcohanna94 | 27. Mai 2016

I think TeslaTap and I are on the same page, same word too haha.

JeffreyR | 27. Mai 2016

@afestini asked, "Unless you have a longer commute, travel a lot or can't charge at home/work, what's the point of a 100kWh battery? ... Definitely offer the biggest batteries possible (and some in between) for those who need it, but let's not ditch the small ones. If they can get over 200 miles from a 55 or even just 50kWh battery, why make it more expensive for no reason with a battery many (most?) may never really need?"

As @wj points out, "[A larger battery pack] is actually about needed a larger battery to send more current instantly to the motors. Linear increases in acceleration require an exponential about of power."

It is about the 20-80% charge range people shoot for you mentioned. In addition it is about charge times. The larger your battery the faster you can charge from near zero to a range you need for the next stop/charge. I plan to get a bigger battery because I drive from NorCal to SoCal pretty often. House to house it ends up being about 350 miles/563 kilometers. If I could get a 350-mile battery pack (or more, but that's really pushing it) that's what I would do. I know I would likely still need to stop in Santa Barbara or Oxnard on the way down and Gilroy on the way up (because I would go faster than the EPA), but then I would have options to even stop halfway and still make it. With only a 200-mile battery pack, I will likely need to stop on a more rigid schedule and probably multiple times.

carlos | 27. Mai 2016

I like this thread!

Marcohanna94 | 27. Mai 2016

@JeffreyR I highly doubt a Model 3 with 350 miles of range. Close to 300 tops.

mos6507 | 27. Mai 2016

"I am your Friendly Neighborhood Over-the-Top-Optimistic Tesla Motors Apologist Fanboy, and stuff."

I respect your honesty.

I think the one thing you can say about Musk is he would rather err on the side of overdelivering even if it means contradicting prior statements about what the vehicles will be like.

It sure seemed to me, due to the miscommunication of Tesla reps at the unveiling, that the decision to add a HUD or some other mystery tech to the dash was a last-minute judgment call on Musk's end, hence it not filtering down to the troops.

Yes, it's true that they need to be disciplined in producing the 3. But Musk is not one to settle for anything other than bleeding edge. If there's a way to make the math work with a larger pack (like 60 vs. 55) in the base model, I suspect he'll do it.

So I really would not seize on any individual statement about what the vehicle will be like at this early stage. The pack has to be able to handle multiple pack sizes so locking the design doesn't necessarily include making the final call on pack capacity. It can happen later when they work out actual economy of scale with the gigafactory.

Marcohanna94 | 27. Mai 2016

I don't understand how this is early stage. This is not like building a mobile phone, the final engineering and production vehicle will be 'finished' in June or July. Big changes such as battery packs will not be changed. Minor things, such as interior fixtures and interior materials have a bit of time but all of it is on a time crunch. Whatever the battery packs will be, I am afraid they are already fixed in place and will not change until the next update to Model 3.

Drdpharris | 27. Mai 2016

@mos6507 -- Spot on.

Sparky | 27. Mai 2016

Actually, I think it's Marco who is spot on.

Red Sage ca us | 27. Mai 2016

The battery cells are not yet being manufactured in massive quantities. So the battery packs are not being manufactured yet either. It is very possible that the battery pack design for initial release will not be finalized until Fall 2016, or slightly after, when the battery cells begin to be produced at the Gigafactory. Please note that the battery packs for Generation II vehicles have been constantly redesigned since the Model S was released. Tesla Motors constantly tests, examines, and evaluates new ideas for their cars. So anything that is an internally developed and manufactured component, that does not rely upon outside vendors for Production, may well be in flux right up to the very last minute. The battery cells and battery packs to be made at the Gigafactory fit that bill.

Marcohanna94 | 27. Mai 2016

The general theory behind my sensibility is while Mr. Musk is a fantastic visionary, he's also a businessman at heart. And smart businessmen don't bank on future technologies being ready for a mass market product, regardless of profit margins. Profit margins on the Model 3 are slim at best. Nothing like the Model S/X. And when it comes to mass producing a vehicle, you pick the "best" even if it's currently the most expensive options now and hope to see profit margins increase as the production runs. They don't choose a product that will be available next year. That's how projects fall behind. Mr. Musk does not want an 18 month delay of Model 3 because that ruins the chances of the EV incentives for M3 buyers here in the U.S. Especially if Tesla hits their 80-90K deliveries this year, which as of Q1 results indicate, they will come very close to 80K cars if production keeps ramping up.

Bottom line is, the batteries will be fairly similar in technology to the S/X batteries. Nearly same density and chemistry. The only difference is packaging. Fewer modules, less weight, clever aerodynamics, and some new and more efficient electric motors. Honestly, the simplicity of the M3 will make it more light weight and more efficient, therefore the batteries needed to make them drive 215 or more miles will be smaller.

I still stand with my theory of 55 kWH and 75 kWH for the Model 3 packs. I think that just maxes out what's technically possible in a battery pack TODAY. Tomorrow's battery packs will be on the refreshed S/X and eventually 3.

Marcohanna94 | 27. Mai 2016

I also think I've repeated myself like 10 times now haha.

Again, I am not trying to start any type of argument. I am just stating "from my experiences of product launches" the hard and cold facts of launching a project this massive. Timing is ESSENTIAL for Model 3. They want to maximize the tax incentives which means, it HAS to begin shipping in 2017 or a lot of people are going to miss out on the $7,500, which could cause a disaster for Tesla with massive amounts of canceled orders due to people not being able to afford a 35K-50K car without the $7.5K incentive.

Drdpharris | 27. Mai 2016

I do not think the opinions expressed are that far apart. I am sure that the specs released are achievable with the technology available today. Cost may still be uncertain, and therefore profit margin. However, EM stated that thes specs were minimums and they would try to better them. I am sure the 3 will be designed to take more than the base battery pack. As to HUD, listening to the demo-ride videos, the drivers worded their answers such that HUD is not ruled out, saying such things as the UI was still in development when asked if the landscape screen was final. Also, the clock on the $7500-wind-down starts when they reach 200,000 cars, so shipping does not necessarily have to start in 2017. However, keeping up with demand means sooner is better, and timing to maximize the rebate would help the most people.

As long as we realize that we are all armchair speculators (albeit educated guessers) this remains fun.

Marcohanna94 | 28. Mai 2016

Dr
For sure though I wouldn't hold my breath for a larger than 75 kWH battery.

Drdpharris | 28. Mai 2016

No, I not holding my breath ... Maybe Jeff Dahn will do some magic (effective research) and we will see it in 2020. I think there will be a break trough in battery technology, but it is unpredictable. At this point slow and steady wins the race.

rharris | 28. Mai 2016

I bet the battery pack will start at 50 KwH and upper end 75 KwH. And I agree with PeterPlt , I think only 2 pack sizes will initially be available.

bb0tin | 28. Mai 2016

Drag is related to the product of cd and frontal area, so a decrease in cd from 0.24 to 0.21, plus a reduction in frontal area will give, I expect, at least an increase of 20% in range over the Model S for the same battery capacity.
The Model 3 cells are taller than the Model S cells. They also package more tightly for the same area. The Model 3 therefore has more efficient packaging. The Model 3 will have it's battery area maximised, just like the Model S. The Model 3 cells are a new and improved formulation so will have more capacity/performance than the Model S cells.
The base Model 3 will have the smallest capacity battery required to get 200+ EPA, and it looks like it will be 215+. This battery pack will not have it's volume filled with active cells.
Tesla can stuff full the battery pack and sell it at a very profitable margin for the high end models. The capacity cost is already less than $190kWh so another 20kWh costs Tesla about $3000-$4000 but they can price it at $10,000+. This greatly improves the gross margin on a sale.
I expect the high spec Model 3 to easily have over a 300 mile EPA and under 2.8 sec 0-60mph.

afestini | 28. Mai 2016

@JeffreyR Your use case sounds like one where I absolutely agree that a big battery makes sense. You travel long distance a lot, so it means fewer stops and/or faster charging.

I'm still looking at it from a point of view where it's over 95% daily commute and home charging, where even in a worst case one charge is more than enough and charging speed isn't too important (if you charge over night, it doesn't matter if it takes 3h or 4h, as long as it's back at 80% the next morning).

Ultimately, I'd expect one pack to fulfill the 215 miles promise, one pack stuffed at max capacity and possibly one in between (if the difference between the two warrants it).

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