Lucid Air EV’s Battery Will Be 113.0 KWh

https://www.caranddriver.com/news/a33797162/2021-lucid-air-517-mile-range-113-kwh-battery/

by clouddrover • 6 years ago

81 185 6 years ago

gambiting5• 6 years ago

I do remember reading an interview with a guy in charge of the electric Clio development, and he basically said something along the lines of "we could have easily put 2x as large battery in the Clio, but then your average driver would need to drive it for at least 10 years before the car became a net benefit for the environment". These massive batteries have an environmental cost is what he was saying.

pedrocr4• 6 years ago

And yet the Zoe (the electric Clio) has gained battery size instead of going lower in price over the years. I wish they'd actually go all in on the ~150km range city focused EVs. Cheaper lower-range cars would fit well a lot of second cars at least in Europe and I suspect in a lot of other places.

bryanmgreen2• 6 years ago

I agree that massive batteries have an environmental cost that has nowhere near been researched thoroughly. I too think that they are not advanced enough to be easily be called a "green" option.

That said, Lucid is not improving range through battery pack addition, but rather through increased efficiency which reduces the size of the pack, which is promising.

From their press release: "Lucid’s (efficiency) breakthrough is not merely just a few percent; we are talking about a significant improvement, which I shall cover further on September 9th."

hn_throwaway_99• 6 years ago

Excited to see more competition in the EV space. Still, press releases are free...

dgritsko• 6 years ago

"...when it comes out in 2021."

My rule of thumb when it comes to all breathless headlines around battery technology is that "I'll believe it when I see it". It's one thing to achieve these specs for batteries when n = (small number), but can they be affordably built at scale?

clouddrover3• 6 years ago

I'll believe it when I see it

See it: https://www.motortrend.com/cars/lucid/air/2021/2021-lucid-ai...

can they be affordably built at scale?

The Lucid Air is an expensive luxury car. It's affordable in the same way that all luxury cars are affordable: not very. It's not a high volume vehicle.

They will be selling a smaller battery version eventually which will be cheaper but still at luxury car prices.

zwily• 6 years ago

Are they achieving the additional range by just using a bigger battery? Or new tech/chemistry? Removing weight from the rest of the car? Better aerodynamics?

If it’s just a bigger battery, it’s not all that interesting. I’m sure Elon could build a prototype S with 1000 miles range if he felt like it. It wouldn’t make sense though.

i_am_proteus• 6 years ago

Agreed; this certainly falls under the category of "huge if true," and in this specific case, also "true if huge."

Mvandenbergh2• 6 years ago

All technology cost and performance forecasts should be indexed by their TRL.

This should also be applied to all stories about new fission reactor technologies. Comparing a cost that's been validated across many units over decades with the "should cost" for a design that hasn't even had gone critical in a prototype is almost meaningless.

voodooranger• 6 years ago

TRL == Technology Readiness Level

https://en.m.wikipedia.org/wiki/Technology_readiness_level

dosshell• 6 years ago

Not that it matters, but for the record: Did you mean _fusion_ reactor technologies?

WorldMaker7• 6 years ago

2021 starts in less than 5 months. I think a lot of people are still so used to seeing 202x dates as "far future" that it's really easy right now to lose perspective that that future is already here.

mmrezaie• 6 years ago

Oh come on, you jinxed it. Now, 2020 will never finish!

dylan6045• 6 years ago

It also doesn't help that half of 2020 has been stuck indoors. We're all taking a skip year, but we just didn't know it.

gibolt• 6 years ago

Lucid's led by the Lead Engineer from the Tesla Model S. The range is from official EPA testing (pre-production). They have already produced a fleet of ~40.

There is nothing to indicate that they won't be able to achieve this in production of their low volume luxury vehicle.

jeremyw• 6 years ago

They don't have EPA testing yet. They used a third-party, FEV North America, with EPA-like methods to arrive at 517 miles.

modzu• 6 years ago

does anyone know why EVs dont use gears for more efficiency?

mamon• 6 years ago

Because it doesn't make sense.

Combustion engines have some limitations that require gearbox to mitigate them:

https://x-engineer.org/automotive-engineering/drivetrain/tra...

Electric engines have none of those limitations, so no need for gearbox.

cmrdporcupine2• 6 years ago

Because they don't need them. Electric motors produce mostly constant torque across all RPMs.

That said, there usually is some kind of gearing as I understand it, but a static reduction, not in the way a combustion engine car is.

bfieidhbrjr2• 6 years ago

Yeah but the Taycan has a two speed gear IIRC to get some extra juice out of the lemon, so to speak.

clouddrover3• 6 years ago

You don't really need better than single speed for your average EV: https://www.youtube.com/watch?v=36H9BVeMYMI

Although the Porsche Taycan does have a two speed gear box which gives it more top end performance: https://www.youtube.com/watch?v=ItCGU7BTBv8

sjwright2• 6 years ago

Because they aren’t necessary for electric motors at anything other than the most extreme applications. They add weight, complexity and expense for no good reason.

(A dual motor design could simulate the benefits of two gears by having different final drive ratios for each axle.)

speedgoose3• 6 years ago

To be pedantic, EV do use gears. Most of them have differentials and some gears with a fixed ratio.

What most don't have is gearboxes to change the ratio. The exception is the Porsche Taycan with 2 gears in gearboxes, the second gear slightly improves the acceleration at high speeds and improves the efficiency at high speeds. Accelerating super fast when you are already above the speed limit is not very useful for most people so most electric cars have no gearboxes, despite the slightly better efficiency. It's too complex and expensive. An electric engine has a lot of torque, you need a really good and expensive gearbox to handle it. It makes sense on a Porsche, but not on a Zoé.

Tesla has another alternative on the cars with two motors. They don't have the same gear ratios. The rear motor is used more at low speeds and the front one is used more at high speeds. It's a bit less fast than the Porsche solution but much simpler and cheaper.

In both cases, having different gears indeed improve the efficiency. I think the Tesla solution is very clever but requires two motors, so it's not perfect either. Most eletric cars have a single motor.

sjwright2• 6 years ago

What’s special about selling a 13% larger battery pack for a much higher price?

tzs• 6 years ago

It's not 13% larger. They purport to be making batteries that are more efficient, so they get 13% more power than Tesla's batter pack with a smaller pack.

Here's an article that talks about this some [1].

[1] https://www.caranddriver.com/news/a33797162/2021-lucid-air-5...

akimball2• 6 years ago

Regardless of their claims, I think it likely that their range gain is attributable entirely to reduced drag coefficient.

bryanmgreen2• 6 years ago

The title should be updated as it is misleading in a critical way.

The word "big" suggests the size and weight of the battery is bigger, which is not the case. That would be entirely unremarkable. Their quote directly states this: "It's relatively easy to achieve more range by adding progressively more batteries, but gaining 'dumb range' that way increases weight and cost, and reduces interior space." He continued, "Lucid Air has achieved its remarkable range whilst also reducing battery size"

A better title: "Lucid Air's EV 113.0 KWh Battery Is More Powerful, Efficient, and Lighter-weight Than Tesla's"

natch3• 6 years ago

Let’s not jump the gun though. We still don’t know enough about Tesla’s 2021 and later batteries. Your suggested headline is built around a comparison to missing information.

Also Tesla’s best battery will be 200kw, not 113kw... I guess they missed that. And Cybrtrk may be higher than that.

But yes reducing size and weight and improving efficiency are all great things! Kudos to them if they can get it into a shipping car at volume.

detritus• 6 years ago

https://www.tesla.com/cybertruck

I had to check - they've not gotten rid of the vowels and a c

Having seen what Elon's at least half to blame for naming this year, I could've fully believed he'd gone that route!

electriclove• 6 years ago

It is all just another click bait headline

speedgoose3• 6 years ago

I think your title is worse because it mentions Tesla, which is extremely clickbate in EV news.

zaroth• 6 years ago

The battery is not more efficient - TFA doesn't mention anything about charging efficiency at all. TFA also doesn't mention anything about the weight of the battery.

The vehicle has a coefficient of drag of 0.21 (versus the Model S Cd of 0.24). Curb weight of the vehicle is apprarently 4630 lbs, lower than Tesla Model S (4,880) perhaps due to reduced weight of the drive-train or other components.

The right way to describe the battery is that it is higher capacity. It may also have a higher charge/discharge rate, or a higher energy density, but they have not made any specific claims here, just rather generic boasting.

mattlondon• 6 years ago

500+ miles range. Nice.

At a constant 70mph, that is over 7 hours continuous driving (...although I wonder how much range decreases at that speed?)

I do wonder what the magic numbe needs to be before people stop complaining that x00 miles is not enough and that they reguarly drive 19000 mile a day etc.

pedrocr4• 6 years ago

I wish we had a standardized test for range at continuous 70/80/90 mph instead of the EPA and WLTP tests. Those are designed for overall efficiency testing when what people really want to know about EV range is how long they can go on road trips. For everything else charging at home every night makes pretty much any EV range enough for the commute and the efficiency is always great compared to gas.

epanchin• 6 years ago

Continuous 70mph under what conditions? On a flat with no wind isn’t very representative of real road tripping.

mcot25• 6 years ago

To go even further I think you want to have tests or simulations with specific air resistance as the drag is actually what causes range loss at higher speeds more than anything else. As an example driving 45mph into a strong headwind is also going to be bad for efficiency. I’d actually like to see some tests/simulations that isolate speed (different speeds in a vaccum) and air resistance (constant speed but different air resistance).

londons_explore2• 6 years ago

efficiency is always great compared to gas

This isn't a given. Money-efficiency in the UK at least is only good if you charge at home. If you pay on-street prices for electricity, you can easily spending more per mile than a gas car.

Eg. An electric car might do 330 Wh/mile. A recharge on the road would cost £3 (connection fee) + £0.30 per kWh. That means if you top up 25 kWh, you'll end up paying £10.50, and able to travel 76 miles, or £0.138 per mile. A typical 2018 gas car gets 50.8 imperial mpg costing £0.108 per mile at todays gas prices in London.

Overall, unless you can charge at home, an electric car will cost you more per mile for fuel/electricity alone.

ndaugherty18• 6 years ago

The article says they did a test @70mph and the battery lasted 458 miles.

bfieidhbrjr2• 6 years ago

The reality is always far worse.

A brand new Model 3 will do 310 miles of range. Only you're not supposed to use the top 10% or bottom 10% unless you absolutely have to, to avoid damaging the battery. So now it's 248 miles of range. Unless it's extremely cold or hot, or you have a heavy foot, or you have a roof rack, or it's uphill... Where 200 miles might be more accurate.

My 18-month old Model 3 will do 301 miles, which means best-case 240 miles reality unless I want to damage the pack (more).

I actually love my Tesla, and the pack degradation is fine, and there are lots of other benefits....

But when someone says "500 miles range" I'm going to read that as "probably ~350 miles real range after a year of ownership and if it's cold or something".

turtlebits2• 6 years ago

You’re overthinking it. Just drive the car as the range reports. There is a battery degradation warranty if the pack does truly get damaged.

I know Chevy bolts have extra capacity so you aren’t causing permanent conditioning at low capacity. Never heard of not driving when at full. Only not to fast charge above 80%, which the car and charging stations manage for you.

And as for cold weather, yes you do lose some range, but in warm weather you gain range. I get close to 280 on my bolt (rated 238) in the summers.

ogre_codes4• 6 years ago

A brand new Model 3 will do 310 miles of range. Only you're not supposed to use the top 10% or bottom 10% unless you absolutely have to, to avoid damaging the battery. So now it's 248 miles of range. Unless it's extremely cold or hot, or you have a heavy foot, or you have a roof rack, or it's uphill... Where 200 miles might be more accurate.

This isn't much different from ICE cars mileage estimates. Getting the actual mileage out of my Subaru is possible if I'm very careful with the gas-pedal, don't have a bike on the back of the car, etc etc. If I drive at 70 miles an hour for the whole tank, my range drops by 15-20%.

turtlebits2• 6 years ago

IME, 300 miles is enough. The problem is charging infrastructure. Tesla got it right building out their own as everything else is a crapshoot.

At least 50% of the time i've tried to DC fast charge, stations just don't work. In fact, there is a station near me that has 2 of 4 chargers not working for the past 2 months. (I've called and used the phone app to report problems)

rconti2• 6 years ago

The FUD is real. When I bought a model 3, it was trying to decide whether I wanted to spend half as much on a commuter-only, or pony up for the Tesla and have a "nice" car I could also take a roadtrip in.

For the "same price as Tesla" EV competitors, you get an admittedly slightly nicer car, with the massive downside of charging infra. And it's just too much money for me to spend to not be able to be confident on a roadtrip.

michaelmior5• 6 years ago

I assume you mean 300 miles is enough "if there is sufficient charging infrastructure." If so, I think that I would agree that would be sufficient for most. Having to stop for a non-trivial amount of time to charge is one of the main disadvantages right now of EVs vs ICE.

michaelmior5• 6 years ago

That would be enough range for me if it weren't for the temperature sensitivity of current batteries. I live in the northern US and pre-COVID I regularly drove trips ~300 miles to visit family. 500 miles range would work great for most of the year, but at least in my current vehicle, battery capacity drops quickly in the cold. This is the main reason why I drive a PHEV and haven't gone fully electric. (That and the fact that my family lives in rural Ontario where public charging infrastructure is very limited.)

mcot25• 6 years ago

The number of kWh of a pack is kind of a meaningless number for comparisons. A larger pack may actually be worse as it adds weight.

They key numbers I want to see are volumetric density (wh/l), gravimetric density (wh/kg), and cost ($/kwh) at the pack level and the cell level. Other key numbers are operating temperature ranges, max charge rate, maximum charging curves, idle energy loss or leakage, and overall efficiency of the vehicle (wh/mi) in many specific testing regimens (different speeds/air resistance, temperatures, and weather conditions.

TheSpiceIsLife• 6 years ago

Right, well you sound like an engineer.

Articles like these are targeting retail investors looking to be ahead of the curve.

mcot25• 6 years ago

Well I am also a retail investor that just made 10x my money with Tesla by understanding the numbers and using the product.

baybal25• 6 years ago

Very true.

There are EVs with inferior cell gravimetric power density, who in the end manage to have superior pack gravimetric density, and superior mass fraction (cell weight/car weight) than Model S.

mcot25• 6 years ago

Yes exactly. Going further than that they may even choose a lower density for cost reasons. Elon responded to me about this when I tweeted him about LFP which have worse density but a lower cost, better thermals and safety. In China they are going to use LFP on the low cost SR+ Model 3.

WhompingWindows• 6 years ago

The sheer storage capacity of the battery is less interesting than the cost. Getting below $100/KWh will reduce EV price to FAR below ICE vehicles; while BEV's are already at parity with ICE on total cost of ownership, BEV's are going to continue the long descent to MUCH cheaper, and $100 is going to be an important milestone.

I think new ICE vehicles are going to be banned in most major economies by 2030, so really, ICE is having its last decade of relevance in new vehicles. Given vehicle replacement cycle is around ~20 years, by 2050 the ICE vehicle stock will be reduced to 99% specialty machines like classic cars, motorcycles, and various heavy equipment for industry.

tachyonbeam2• 6 years ago

I have been a TSLA investor for a few years, I believe in electric vehicles. At 100$/KWh we're talking 5000$ for a 50KWh battery back, which is plenty enough for most people. This could allow us to see $15K-20K electric cars in just a few years, maybe before 2025, which is awesome. Very soon buying a gasoline vehicle, in a modern economy, will have people giving you weird looks.

What does have me a little worried though is that most of the world doesn't live in a wealthy city. As electric cars rise, gasoline prices will come down, which will keep gasoline attractive for a while, particularly in poorer countries. Failing ICE vehicle companies will try to sell their gas vehicles to these poor countries as well, and our used cars might end up there too. In other words, poorer countries could keep gasoline cars going for another 30 years after they've been banned here. What are we going to do about that? We're all breathing the same air.

AgloeDreams7• 6 years ago

Bigger problem: More than half of Americans do not have a garage to park their car in to charge. Fast charging is great for road trips but it's got nothing on gas fill ups..yet.

evandijk70• 6 years ago

If the oil price drops, at least shale oil production won't be profitable anymore, reducing CO2 emissions and eliminating the pollution resulting from shale oil mining.

Shivetya2• 6 years ago

I really wish people would stop with accepting lower range BEVs. To truly replace petrol vehicles we should not compromise or suggest drivers do so. Hence hit the three hundred mile mark and go from there with luxury and higher priced models pushing far beyond those numbers; as in 500+

People need to remember, the range is best case range and full charge. This is subject to driving conditions and especially the effect of weather. Lower pack sizes do not charge nearly as quick and this too will hinder acceptance as some will see charge times as a detriment. Wide spread acceptance means more people with a BEV and no home to charge at which means charge times are a real concern

So, don't let manufacturers off the hook. Telsa set a bar for range in 2013 that most are barely crossing in range and upped it with the TM3 and TMY. Mercedes and BMW both have offerings coming in with more than 300 miles range. Let us count this low 200 club as we did the sub 100 range, a good first EV for the manufacturer but not what is expected from true BEVs; remember many of the sub 300 club were petrol platforms adapted to electric.

samatman3• 6 years ago

In short? We're going to tolerate it.

Embodied energy is a significant fraction of total emissions in a vehicle. It's unclear whether early retirement of existing ICE vehicles is a win; I'm sure someone has done the analysis, and I'm kind of hoping someone will jump in and provide a link to it.

Economics is an imperfect proxy for this, but not uncorrelated: if it makes sense in dollar accounting to sell the ICE fleet to developing nations to be used up, that suggests (but does not prove) that it makes sense in carbon accounting as well.

baybal25• 6 years ago

Getting below $100/KWh will reduce EV price to FAR below ICE vehicles;

LFP cells with volume discounts were already sold for less than $100/KWh for a few years. Not much changed.

Cheapest EVs in developed countries have passed the $20k barrier, but I don't see everybody falling for EVs.

The type of people who are happy to have just anything to drive buy into something like https://runhorse2020.en.made-in-china.com/product/uwcniFmDXJ...

But even they switch to cheapest, crappiest IC sedans starting at $7k in China (say thanks to $500 per ton steel)

tachyonbeam2• 6 years ago

Tesla is aiming for $100/KWh at the assembled battery pack level rather than just at the battery cell level, so that's a bit of a different milestone, but we're definitely getting there.

Cheapest EVs in developed countries have passed the $20k barrier, but I don't see everybody falling for EVs.

AFAIK most of the EVs with a 200+ mile range are above 30K, even after incentives. Some of them are not that amazing either. It will take some time for the prices to come down more and for the offerings to improve. I rode in an VW E-Golf when I ordered an Uber the other day. The acceleration was great and it was a nice looking vehicle, but the base model is 32K and the range is just 125 miles.

ogre_codes4• 6 years ago

Cheapest EVs in developed countries have passed the $20k barrier, but I don't see everybody falling for EVs.

Not sure what you mean here, EVs are easily the fastest growing auto-segment.

Massive EV sales growth is why all the auto makers are pushing hard on their EV efforts. EVs aren't matching ICE vehicles in volume yet, but they are grabbing big market share where they offer competitive products.

Look how quickly manufacturers jumped on making electric truck announcements once Tesla made it clear the Cybertruck was coming. From the looks of it, electric trucks are going to be big.

snovv_crash2• 6 years ago

LFP has poor energy density compared to LiIon. It's great for static installations (powerwalls etc) but putting in cars, phones, drones etc is a fools errand.

imtringued3• 6 years ago

The Renault ZOE is one of the most affordable EVs and it certainly didn't break the $20k barrier even with subsidies.

agumonkey2• 6 years ago

Let's keep in mind that even a 2020 EV on par with ICE TCO is also very much less polluting ;)

Just a tiny reminder

michaelmior5• 6 years ago

Is this actually true when taking into consideration the current production process of EVs? Certainly operationally EVs are less polluting, but I'm not sure where things are at considering the entire pipeline. (I'm not intending to bash EVs at all here, I have a PHEV myself and I'd love to get a BEV when the range/cost suits my needs.)

gok2• 6 years ago

Lucid is explicitly targeting the very high end of cars; the Air will probably be around $150,000. I'm not sure they care too much about cell price.

akimball2• 6 years ago

60,000 USD, per the article

jillesvangurp• 6 years ago

2035 in the UK. That's when the current (conservative) government wants to ban sales of ICE cars. I'd say the economic value proposition of ICE is going to collapse long before that. And few companies will be buying ICE vehicles if they can avoid it long before then.

100$/kwh probably has already happened. It's hard to confirm this but I suspect that Tesla is making a nice profit on their cars at this point mainly due to them pushing hard to get production cost down. At this point, they are supply limited so they have little reasons to eat up their profit margins. Competition will fix that.

I'd say the next benchmarks here are going to be 400wh/kg (3-4 years out according to Musk) and energy prices for clean energy bids dropping below 1 $ cent per kwh. Basically, we are talking about reductions in sales price and operational cost for most vehicles. At some point the math stops being interesting because we're merely debating by how many of orders of magnitude ICE is more expensive. The cross over point for some forms of commercial transport was probably a few years go; judging from how hot the market for e.g. electrical deliver vans or city buses are.

gambiting5• 6 years ago

Well, the UK government said that they want to do that, and yet proposed no actual plan on how to do it. Previously at least you could still buy a hybrid - under this new plan it's only going to be electric vehicles, no hybrids allowed. Which is great, except that the government hasn't answered how all of these electric cars are going to be charged? I have a house with my own driveway so it's not a problem, but what if you live in a terraced house? Apartment? Rent a place? The subsidies and grants for both cars and chargers are being cut left and right, so who is going to build the infrastructure? Private sector? Like ionity is, where they charge £0.69/kWh, making it cheaper to drive a diesel than charging with them(and also charging 6x more than average UK kWh price for the privilege). I've heard an argument that places of work will provide charging points - but why would they? At my own work they said the parking lot is owned by an external company that is not interested in doing any improvements whatsoever so that's not happening, after a massive deal of effort they finally managed to install....2 charging points for a building of 1500 people, you can book the charging session in half-day slots and they are never free. You'd think the "free market" would just solve this problem, but it seems incredibly slow to do so.

abraxas2• 6 years ago

With the relatively small size of the place and the mild weather the UK as a whole could probably switch over to 60kWh EVs tomorrow and nobody would bat an eyelash. Things will take longer in places with greater distances and more extreme climates.

abledon• 6 years ago

Lets just see what they announce on Battery Day... that nano-tech teaser image...

ogre_codes4• 6 years ago

The vehicle is more efficient than the Model S Long Range Plus, which has a 100.0-kWh capacity and 402 miles of range.

It always makes me cringe when I see headlines which compare potential products to a shipping product. It shouldn't be surprising that a future product is better than a currently shipping one.

A year ago Lucid was bragging that they would have a 400 mile range. Now Telsa is shipping a car with a 400 mile range. So Lucid has to up their game.

AgloeDreams7• 6 years ago

Whats interesting is that they are focusing on the current Model S and zero mention of the 3, which has a significantly better efficiency due (in addition to the smaller size, admit-ably) to the fact that the newer 3 design, powertrain, and chassis was a rework that is far superior to the, basically, 9 year old, Startup-developed, Model S. Next-Gen Model S will bring not just larger packs but Model 3 lessons in weight and their claims probably wont pan out, even if true.

tyfon• 6 years ago

The current Model S is actually on par with the model 3 in terms of battery and drivetrain. They continuously update it.

They stuck the Model 3 motor type into the front of the Model S and primarily uses that for driving. You get to use the less efficient induction motor in the back for high accelerations. The chemistry in the battery is also the same but in a slightly different format.

I have a Model X and it's also updated in this fashion. They have come a long way since the 2012 Model S.

I suspect they will come out with a 100 kWh Model 3/Y though and it seems that the efficiency/range should be compared to these as you say instead of the big cars.

slg2• 6 years ago

The first sentence of the article:

After surprising many with the Air's 517 miles of EPA-estimated range...

A few paragraphs later in the article:

During a real-world ride along with Lucid in one of the company's prototypes traveling at 70 miles per hour on the highway, the Air achieved 458 miles before depleting its battery. The automaker still needs to deliver a production vehicle to the EPA before it has an official EPA number. It expects to do so in early 2021 when the Air goes into production.

Isn't that opening incredibly misleading? The car does in fact not have 517 miles of EPA-estimated range. The company is projecting 517 miles of range once the EPA tests it, which has not happened yet. So why are they calling the 517 number "EPA-estimated"?

conception• 6 years ago

EPA test is not a real world test. It’s a specific format.

slg2• 6 years ago

The EPA is a government agency not a test. Calling it "EPA-estimated" implies the EPA is the one who did the estimating and not that it is a projection of what the car will get on the EPA's test.

dylan6045• 6 years ago

Does the 70mph have an effect? In ICE, there is an MPH window where the engine is most efficient. Driving outside of that window will lower the miles per gallon and the total miles per tank. Is there a similar sweet spot for EVs?

Klathmon4• 6 years ago

The "most efficient" speed is pretty shockingly low, like 25mph to 45mph low depending on if you have "overhead" loads like AC/heat/lights/etc... (for a Tesla Model 3 at least)

And the 70mph does have a MASSIVE difference. Anecdotally, going from 65mph to 75mph in my Tesla absolutely destroys my range (last time I checked, the extra 10mph there would reduce my range by about 60 miles).

But that can be misleading in the real world. If you care about "time efficiency" as in "what speed should I drive to complete a long distance trip in the least amount of time", the most efficient speed for Teslas is something like 90mph! That's because the Tesla superchargers are so fast that they make up for the loss in efficiency from going much faster.

This is a good video on someone that actually did the testing to figure that out:

https://www.youtube.com/watch?v=cS2Vp9Y_jrc

abraxas2• 6 years ago

Even 458 miles (737 kms) of highway EV driving at 70mph (112 km/h) is phenomenal. If this is coupled with a relatively fast charger infrastructure (150KW+) this means game over for fossil cars. When you can drive for 6 hours or more on a single charge there is absolutely no inconvenience factor in owning an EV at that point.

PossiblyKyle• 6 years ago

A lot of countries are still interested in fossil cars because they can slap their bullshit taxes on them and the gas, so I wouldn’t expect an instant transition, as it’s going to severely impact lobby-backed revenue streams

zackmorris• 6 years ago

I procrastinated for an hour and did some quick research to see how much the drag coefficient and rolling resistance affect fuel economy:

https://www.nap.edu/read/11620/chapter/5#39

Specifically a) city (top) and b) highway (bottom):

https://www.nap.edu/openbook/0309094216/xhtml/images/p2000f6...

For an internal combustion, midsize passenger car, including standby, here are the losses:

City:

  Engine + driveline + standby: 85%
  Aero: 3%
  Rolling: 4%
  Braking: 6%
  Accessories: 2%
  ---
  100%

Highway:

  Engine + driveline + standby: 78%
  Aero: 11%
  Rolling: 7%
  Braking: 2%
  Accessories: 2%
  ---
  100%

Looks like Tesla motors are 93-97% efficient:

https://www.pcmag.com/news/report-tesla-model-sx-upgrading-t...

And regenerative braking is 80% * 80% = 64% efficient, or 36% costly (about 1/3 as much energy wasted):

https://www.tesla.com/blog/magic-tesla-roadster-regenerative...

I'll just run the math for an electric car with a 95% efficient electric motor, assuming 0% driveline losses with direct drive and no transmission, with no standby losses:

City:

  Engine + driveline + standby: 5%
  Aero: 3%
  Rolling: 4%
  Braking: 2%
  Accessories: 2%
  ---
  16% (already 6.25 times more efficient by going electric)

Highway:

  Engine + driveline + standby: 5%
  Aero: 11%
  Rolling: 7%
  Braking: 1%
  Accessories: 2%
  ---
  26% (already 3.85 times more efficient by going electric)

Rescaled to 100% by multiplying each term by (100/total):

City:

  Engine + driveline + standby: 31%
  Aero: 19%
  Rolling: 25%
  Braking: 13%
  Accessories: 12% (rounded down to make 100% total)
  ---
  100%

Highway:

  Engine + driveline + standby: 19%
  Aero: 42%
  Rolling: 27%
  Braking: 4%
  Accessories: 8%
  ---
  100%

So we can see that city driving is dominated by engine efficiency and highway driving is dominated by aerodynamic efficiency. But both lose about 25% (1/4 of the energy!) to rolling resistance.

Googling "mileage loss percentage due to drag coefficient" and "mileage loss percentage due to rolling resistance":

http://www.arcindy.com/effect-of-aerodynamic-drag-on-fuel-ec...

  For passenger cars this means that aerodynamics is responsible for a much higher proportion of the fuel used in the highway cycle than the city cycle: 50% for highway; versus 20% for city. This means that if you make a 10% reduction in aerodynamic drag your highway fuel economy will improve by approximately 5%, and your city fuel economy by approximately 2%.

https://www.nhtsa.gov/DOT/NHTSA/NVS/Vehicle%20Research%20&%2...

  A 10 percent decrease in tire rolling resistance resulted in an approximately 1.1-percent increase in fuel economy for the vehicle. This result was within the range predicted by technical literature.

Converting these for electric in city and highway by multiplying by 6.25 and 3.85 respectively:

City:

  Each 10% reduction in aerodynamic drag increases mileage by 13%
  Each 10% reduction in rolling resistance increases mileage by 7%

Highway:

  Each 10% reduction in aerodynamic drag increases mileage by 31%
  Each 10% reduction in rolling resistance increases mileage by 4%

Comparing drag coeficents:

https://en.wikipedia.org/wiki/Automobile_drag_coefficient#Ty...

  Lucid Air: 0.21
  Tesla Roadster: 0.35
  Tesla Model S: 0.24
  Tesla Model 3: 0.23
  Tesla Model X: 0.25

So the Lucid Air has about a 10% better drag coefficient than the Tesla model 3, which gives it (at most) 13-31% better range city-highway. I think this is a liberal estimate, and that drag coefficients will never be below about 0.20, so improvements here will probably be marginal from here on out.

It seems to me that a better return on investment might be to fix tires. Someone needs to think outside the box on this and create a tire that acts stiff at high speed, but still grips while cornering and braking. Eliminating this resistance would add 100 miles to electric car range.

I ran this math from a first order perspective, to give an idea of relative costs. I'm sure it's off (since drag is nonlinear), but it helps visualize where the energy goes. Seeing that accessories use as much or more energy than regenerative braking was eye-opening for me.

Oh and you don't even want to know about bicycles. The upright position is the worst possible, and wastes most of the rider's energy. I wish recumbants were safer and more affordable, although this matters less each year with improvements in electric assist, mostly from reduced cost and better batteries.

ebg13• 6 years ago

a tire that acts stiff at high speed, but still grips while cornering and braking

Having a higher PSI rating and an air pump + brake-controlled deflate valve could do this.

throwawaysea• 6 years ago

Do the EPA estimates account for weather changes (hot and cold weather, as opposed to moderate temperatures)? How trustworthy is the 500 mile claim?

lr• 6 years ago

Given the number of job openings (491) for the company, who actually works there now? By that I mean, how can they already have a car, or know these kinds of specs, when there are that many positions to be filled...

nharada• 6 years ago

I wonder if this will become the new high end luxury EV, at least until Tesla does a refresh of the S. My impression is that right now the current Model S isn't really that popular because the 3 is functionally similar at a much lower price point, but clearly that segment of the market willing to pay 120k+ for a top tier vehicle exists because they paid it when the S was the only game in town.

Zanni2• 6 years ago

I have a Model S and a Model 3, and I actually prefer the 3 (though I generally prefer sportier cars to luxury cars). The smaller size makes it more nimble, the lack of air suspension gives better road feel, the horizontal orientation of the central screen seems more effective, and I don't miss the dash at all. The only things I do miss from the Model S are the much more comfortable steering wheel, AM radio (weirdly missing on the Model 3), and a hatchback. If I were looking for a new EV today, I'd probably be looking at a Model Y.

odysseus• 6 years ago

What is more comfortable about the Model S steering wheel?

Lucid Air EV’s Battery Will Be 113.0 KWh

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