I wonder if anyone has estimated the impact of "simple" engineering changes on the progress of electric cars.
I have seen things that extrapolate out battery progress, so if batteries become cheaper/lighter/more powerful in a similar way they have in the past then that has a big impact on EVs, dropping their price and/or increasing their range.
But a lot of things seem fairly simple, if not obvious except with hindsight e.g. heated steering wheels and seats instead of air heating, heat pumps rather than resistive heating, puncture resistant tyres rather than carry a spare, led lighting, replacing side mirrors with cameras for lower drag etc. How much can straightforward, no new tech, improvements in all these areas actually help if you add them up?
Tesla's original major innovation in this area was realizing that, if batteries are expensive, then the way to make an electric car people want to buy is to make it really expensive and really good, rather than trying to cut costs everywhere and ending up with something moderately expensive that sucked.
They don't really eke out efficiency the way you describe. They have heated seats standard and use aluminum body panels to cut weight, but it's still a big, heavy car. They're among the least efficient EVs out there. Tesla doesn't use a heat pump for cabin heating. Heated seats cut down on heating energy a little bit, but speaking from my own experience, I'd say they let me drop the cabin temperature by only 2-4 degrees (F). Energy consumption from lighting is insignificant (Tesla didn't start using LEDs until recently, I have halogen bulbs), and the weight saved from not carrying a spare tire is pretty minor. I believe they omitted it manly to have more cargo space. The main reason they go so far is because the batteries are several times larger than anyone else's (save the Bolt).
Certainly it helps. Tesla keeps pushing to replace side mirrors with cameras, as you mention, which would add maybe 3% to range. On the other hand, the Model 3 will have a steel body, since apparently cost matters more than weight there. Batteries seem to be far and away the most productive area of improvement.
> I wonder if anyone has estimated the impact of "simple" engineering changes on the progress of electric cars.
Many years ago, I was browsing through an old Hot Rodding guide to Harley Davidson motorcycles. (Don't ask why.) One line from the book that made a lasting impression was a comment to the effect that real progress was more likely to be found in one hundred 1% improvements than one 100% improvement.
As a practitioner and observer of engineering, this really resonates as something with a lot of truth. Even for seemingly transformative changes, they're backed with a long series of incremental refinements until they're actually useful. T
Let me see, people are already really upset by cellphone radiations, which are non-ionizing and therefore can only be harmful from the heat it generates.
You would need marketing masterminds to sell this.
That is illegal in the US: there's a regulation that limits microwave power levels outside of an oven to little enough that it doesn't significantly heat anything.
Probably good as microwaves behave very unpredictable in the complex fat-air-water boundaries in a body.
It is hard to rule out that a focused reflection from the head accidentally heat up a part of the retina just a few degrees, which might blind someone.
My guess there is quite a lot of this low-hanging fruit improvements. Electric cars its a young technology than can go through tons of incremental changes that will add up.
E.g. compare gas cars over decades. There were tons of improvements that allow much better fuel efficiency.
>compare gas cars over decades. There were tons of improvements that allow much better fuel efficiency.
Electric motors are old technology. Most of the improvements in electric motors have already been achieved, just like the internal combustion engine.
Most of the things that original poster pointed to are improvements brought from gasoline cars (only the heat pump for heat is somewhat unique - gas engines have plenty of waste heat so they don't need that)
That's my point though, it's not that they invented new technology, they just sat down and said "heating is using X% of the battery, how can we lower that" and because it's an EV rather than an ICE car, different decisions would be made when picking from the existing range of off-the-shelf tech. There will be lots of these little decisions, and they'll probably add up, now that people are over the hump of "how can we build a modern EV" and just building incrementally better cars.
If you would only keep bodies warm, wouldn't you constantly have steam coming out of your mouth in cold weather? Wouldn't you have steamy windows without heating or air conditioning? What about babies in baby seats?
18650s are pretty much the only way to get decent energy densities and allow for high power output. What a lot of people don't know - which I find fascinating - is that discharge rates on batteries are set mostly by how much heat the battery can dissipate safely, and not as much by the cell chemistry itself. Looking at a random 18650, it may be able to (in theory) put out 200 watts, but the cell would be permanently damaged by the intense heat produced.
As a result, if you build an enormous single cell battery, even though it seems futuristic, it'll be horrible at distributing heat. A Tesla pack that was consolidated into one cell would basically be an enormous furnace at any reasonable discharge rate, and they'd have to discharge it at a very low rate in order to prevent it from permanent damage and/or fire.
If there's one thing to call "primitive", it would be the new low cost 21700 battery cells Tesla is producing; these have shockingly low power and energy densities, and disappointing cycle limits. They are cheap though, and that seems to be why Tesla's making them: for lower cost vehicles.
> If there's one thing to call "primitive", it would be the new low cost 21700 battery cells Tesla is producing; these have shockingly low power and energy densities, and disappointing cycle limits. They are cheap though, and that's why Tesla's making them: for lower cost vehicles.
Two claims here - that the batteries have lower energy density, and that they're intended only for lower cost vehicles - go against the common narrative among Tesla people. Can you provide any background on this?
Cars aren't particularly size constrained, even if the Model S battery was twice the size it is now it wouldn't have a huge impact on the size or performance of the entire car.
Weight is important; doubling the weight of that battery would affect the S significantly.
Obviously battery cost is important; doubling that would add a huge blow to the bottom line of the S let alone the 3.
So it's not surprising that Tesla would optimize for cost, weight & other engineering factors such as cooling and reliability over size.
Thanks, and that's all obviously true, but I guess I asked for background when I should have asked for some citations. But owenversteeg indicated in another comment that his information is "not public yet," so I'll have to wait, I think.
(I'm almost certain his claim that the new cells are meant solely for the "lower cost vehicles" is wrong)
I didn't read that into owenversteeg's claim. Tesla is making and desiging its 21700 for the Model 3; they couldn't hit volume or cost targets without it. It's not being designed for the S; but that doesn't mean that they can't use it in the S later.
At least that's how I read owenversteeg's comment.
TL;DR 21700s produce less power (not necessarily energy) for the same cycle length and weight, so Tesla will either have to reduce power consumption of their high end vehicles -or- add more batteries, which adds weight. Both of these things reduce performance.
I'll be honest: I've got much more knowledge about batteries than I do about Tesla's strategic direction.
I do know that there are currently problems with Teslas sustaining their power output when on high performance mode. Since the power density of 21700 cells will almost certainly be less than 18650 cells (this is basic physics) [0] I think they will use 18650s for their performance vehicles. However, I could be wrong; they -could- simply increase the number of cells used and make the vehicle heavier. Strategically, I would use 18650s (at least with the performance cars) if I was Tesla. However, for PR reasons they may choose to use 21700s and compromise the performance of the performance cars.
My claim that they have a low energy density is on less strong ground, of course. As Musk said during the Q3 2014 conference call, "show me the cell, not the powerpoint." I only have powerpoints and no cells. However, the powerpoints I do have show that the energy density will be between 220 and 260 Wh/kg. They may be up to 280 Wh/kg. But I doubt that they'll beat the current maximum of 310 Wh/kg that you can get today.
Tesla does a lot of really cool stuff, but there's a bit of a Tesla reality distortion field going on. For example, this post here [1]. Some genius speculates that batteries grow at a 5.94% compound rate, and then extrapolates to assume that Tesla's cells will reach 350 Wh/kg. Here's the kicker: li-ion battery cell capacity has been practically stagnant for 11 years. In some of these 11 years, the cells have gotten cheaper, but not by much. If we truly had grown at that 5.94% compound rate for the past 11 years, we'd currently have a 528 Wh/kg cell today.
Li-ion battery energy density grows in spurts. Realistically, there have been a few major improvements, with very small incremental improvements in between. For example, in 2001 we were at 180 Wh/kg. In just a handful of months we jumped to 260 Wh/kg, then to 280 Wh/kg as manufacturing processes improved. In the last 11 years, however, improvements have been maybe a few Wh/kg per year, and there have been literally zero improvement whatsoever in the past four years, by anyone.
I think Tesla - may - get a bit north of the 310 Wh/kg we can get today, and I'm confident in their ability to reduce costs, but I don't expect anything revolutionary (energy density wise) like Musk implies in his presentations. I'd set the threshold of 'revolutionary' at 400 Wh/kg, a 29% improvement from today.
For future-me-check-if-I-was-right purposes: these estimates are for Tesla's cells released in early 2017.
[0] The larger a cell is, the lower its theoretical power density must be. Power density is a function of power dissipation, and larger cells are worse at dissipating power. These new cells are only a few millimeters wider, but that's enough to increase their volume by 50%, which means their power density will almost certainly suffer.
Sounds like the 21700's have 50% more volume, likely slightly less than 50% more energy, but lower peak power output because of heat issues caused by a higher volume to surface ratio.
Telsa seems to be selling the new battery factory as a prerequisite for the model 3. Both for the volume of batteries and the cost.
However the model 3 is smaller, less air drag, less rolling resistance, weighs substantially less, and (from what little telsa has said) will be much slower to accelerate.
The 21700s should be cheaper to build a battery pack out of, less temp sensors, less connections, less monitoring circuits, and less labor.
So maybe the 21700 based battery packs will be used across the different teslas and provide the cheapest way to hit a given range. Then the 18650 based packs (that can deliver a high peak power because of better cooling) will be more expensive, but provide better 0-60 times.
Are you comparing the Tesla 21700s with all the commercially available 18650s, or with the specific 18650s Tesla uses? It's possible Tesla doesn't use the most energy dense 18650s available, so their 21700s could be an improvement for them.
Also, are they currently limited by the heat dissipation? If not, increasing the volume per cell might not be as much of a problem. The linked article mentions that they doubled the number of cooling loops per module, which might already be anticipating an increase in heat to be removed.
> Are you comparing the Tesla 21700s with all the commercially available 18650s, or with the specific 18650s Tesla uses? It's possible Tesla doesn't use the most energy dense 18650s available, so their 21700s could be an improvement for them.
For reference, Tesla's current cells are about 215 to 225 Wh/kg; they are not the most energy dense cells you can get. What I'm comparing are Tesla's new cells to the best cells out there. The reason why I do this is because that's what Tesla fans - and Elon Musk - repeatedly do. Also, I'm almost certain that Tesla's new cells will have a higher energy density than 215-225 Wh/kg; if they didn't, they'd be on par with batteries from a decade and a half ago, which would be pretty pathetic.
> Also, are they currently limited by the heat dissipation? If not, increasing the volume per cell might not be as much of a problem. The linked article mentions that they doubled the number of cooling loops per module, which might already be anticipating an increase in heat to be removed.
It's complicated. Technically, at the rate of discharge that Tesla uses right now, they shouldn't be. Teslas right now discharge their 65-100kWh pack in 3.5 to 5 hours. That's about 20 kW power continuous. There are roughly 6000 to 9000 cells per pack, so very roughly you discharge, while driving, between 2 and 3.5 watts per cell, so around 0.2C discharge. However, Teslas have their packs in an enormous, insulated, heavily managed sealed blob of batteries. This confines the heat to the pack, which requires their water cooling system.
Another complicating factor is that heat dissipation matters in a few different contexts. First, there's the important matter of getting the heat from the inside of the battery to the battery surface; this is a matter of battery design and solved by the people that make the batteries. Then, there's the matter of what you do with the heat once it's at the battery surface (Tesla water-cools their cells); this is a problem for whoever makes the battery pack. Then there's the problem of what to do with the heat in general; now that you've drawn the heat away from the batteries and into the heatsinks or water, how do you cool your hot water/hot heatsinks?
Switching to 21700s 'only' changes the first part of the equation - heat dissipation within the cell - but this is one of the trickiest parts to deal with. You can put a water cooling system on the outside of your battery, but you can't put a water cooler in individual cells. You can change the chemistry of the battery to better dissipate heat, but changing the chemistry of course also changes the battery's characteristics: energy/power density, cycle life, weight, cost, etc.
Power density I can see. It would be harder to get the heat out of larger cylinders.
But how could the 2170 possibly be less energy dense? You have more active material per unit casing, so it almost certainly is more energy dense, based on geometry alone. Add the fact that you will have fewer connections, and the pack will be more energy dense as well.
The gains in energy density due to casing/connections are generally negligible. For reference, individual 18650s can range from 42 to 52 grams.
In regards to "But how could the 21700 possibly be less energy dense?" the answer is "Cause batteries are magic." Batteries are weird; we know how they work, and how we should be guaranteed to improve energy density if we do x, y, and z. But when we do x, the batteries explode; if we do y, they only last a few cycles, and if we do z they heat up too fast.
If it was my head on the chopping block and I had to explain why the 21700s weren't as good, I'd say 'heat', but that's about as useful as saying 'magic', to be honest, and this is because pretty much every time there's a problem with batteries, it's due to heat. High power discharge? Heat. Cycle life? Heat. Thermal runaway? Well, duh, heat. Chemistry works in the lab but not in reality? Heat.
Eventually, you get tired of seeing heat as the source of all your problems and move to Siberia. But in all seriousness, as I said in the comment you're replying to, I think it's certainly possible Tesla's 21700s are better than the current max energy density, I just doubt that they'll get anywhere near Musk's claims of an energy density revolution.
Also worth noting that Panasonic's best 21700s are less energy dense than their best 18650s. (Panasonic is supplying the battery tech.) Another example of 'batteries are magic'.
Doesn't the number just refer to the size? 18mm x 65 mm vs 21mm x 70mm? Density and all other specs vary from manufacturer to manufacturer and model to model, AFAICT. Or do we have more information about the 21700 that Tesla's producing or am I just wrong?
I don't know about the Gigafactory 21700, but Sanyo/Panasonic has a commercially available 20700 with 247.19 Wh/kg, compared to 258.97 Wh/kg for one of their most energy-dense 18650s.
Yep, the numbers just refer to size/form factor; a potato could be an 18650 if it was the right shape.
However, pretty much the only energy- and power-dense cells commercially available are in 18650/26650 format. I specifically have information about Tesla's new 21700s but I'm not sure if that's been made public yet. I believe it's public that the energy/power densities are low, as are the costs, but I'm not sure if specific numbers have been released yet.
It's important to separate 21700s as a whole from Tesla's 21700s. 21700s today don't look too great, and even the best have worse energy density, worse power density, and worse cycle lifetimes than the best 18650s [0]. Tesla's 21700s, on the other hand, are scientifically proven to cure cancer, protect your vehicle from nuclear weapons, and can charge from zero to full in 0.3 seconds using only a potato battery and a paperclip.
I kid, of course, but this is why I believe that 21700s will probably be lower energy density: a) current 21700s have a low energy density, b) heat is tricky, and c) Musk wants to make cheap cells, and optimizing the last few Wh/kg to push him over the edge is expensive.
I do concede it's certainly possible they'll be over 310 Wh/kg, but I find it unlikely.
I think that a very likely outcome is that when the cells are released, we find out that we're both right. For example, if they have a density of over 310 Wh/kg... at 0.1C discharge or something similarly low. But at 1C or 5C or 10C, the energy density falls to around 200 Wh/kg.
[0] Sanyo's cells are the current leaders, about 230 Wh/kg. With 18650s the leaders are between 280 and 310 Wh/kg depending on how you measure capacity (cutoff voltage, discharge rate, cooling, etc.)
> discharge rates on batteries are set mostly
> by how much heat the battery can dissipate safely
Just a few comments up smart people are discussing the problems of heating the cabin. Why isn't cabin air being pumped around the batteries to heat the cabin and cool the batteries?
Musk has stated several times that this rather simplistic architecture works best for them. Tesla has evaluated other cell and pack designs, and still maintains that cylindrical cells are optimal. The Model 3 pack will use newer 2170 cells, same cylindrical format but larger, produced at the Gigafactory.
It only seems primitive until you try to figure out how to keep thousands of batteries all at the same charge level cycle after cycle. If even one manages to have more charge than the others in the pack, it could overcharge and catch fire.
Battery management has been the biggest problem among the DIY EV crowd and is responsible for a large number of fires.
18650 is mass manufactured: there are machines and robots to get consistent quality. You can get batteries in pretty much any size you want - but they will be made by hand and have the expected quality variations from hand made products.
I know this is a joke but you really couldn't, traction (friction) plays a huge role in 0-60 times and something so light would not have that much traction.
The above has some better details but the one I cannot find is weight of the pack, assumptions put it near 1300lbs. Weight is the one area batteries suffer compared to other alternatives and it needs to be addressed because weight is one area car makers are trying real hard to solve.
Each module has six groups connected in series, and each group has dozens of cells connected in parallel, each cell with its own tiny fuse (see the pictures in the article). If one cell shorts, the fuse removes it from the group, while the rest of the cells in the group is enough to keep it working. And the active cooling removes the heat released from a failing cell, so it won't overheat its neighbors.
My guess would be strict quality controls on each individual battery combined with a sophisticated battery management system.
I've long thought that one of the reasons Tesla built their own battery factory is so they can be absolutely assured of the consistency of the batteries. If the charge rate, discharge rate or internal resistance of an individual battery varies from the others over time, that's when battery packs tend to catch fire. Well, one of the reasons battery packs tend to catch fire, anyway.
Flat cells are great if you're trying to build a flat product, where z space is much more critical than x and y. However, flat cells have an unfavorable effect on specific capacity (both weight and volume) since you need two flat sheets to package the display top and bottom, sandwiching a relatively thin active cell, instead of a single cylindrical package wrapped around a larger volume.
In another comment [1] in this thread, owenversteeg says that Tesla batteries are not space-constrained, but rather weight-constrained, and that the cylindrical shape is only suboptimal in its space efficiency, not any other important design parameters.
My understanding is that the sheer size of Tesla's battery pack is too large to take a layered approach - at least across the whole size. That forces the designers to go with a segmented approach, in which case the cylindrical is tried and true.
From a safety perspective, it also has many more years of data/research behind it. It would be more tolerant to defects. Trying to create small sheets that are then rolled up is easier than creating big sheets, just like smaller silicon processors have better production rates than ones of equal complexity but larger surface area.
Between that and the ever so sliiightly higher capacity cells they already adopted, I can't see them getting any more performance out of the existing tech.
That, and 100kwh for a Model S battery is pretty damned good, could probably set a 650+ mile record under special handling (current record is 550 miles on a 85D).
Out of the existing tech, no. But within a couple of years the Model S will probably transition to the new 2170 cell [0]. I belive production has already started at the Gigafactory, though the Model 3 will probably have priority.
It may require some dimensional changes to the Model S though, as the cells are longer. So it may not be compatible with the existing versions of the Model S.
That comment, I think, is going to have to do side by side comparisons of the relevant figures from the manufacturer specification sheets.
Not only that, there are different grades. A 18650 is a size and voltage specification. As in, it's like calling a battery a AA or AAA: any AA or AAA fits into a device and makes it run, but some AAs and AAAs last a lot longer than other batteries in flat out runtime, or survive usage in abusive devices, or in extreme weather conditions, or so forth.
There are low grade 18650s just as there are high grade 18650s. Maximum capacity isn't the only way to measure a battery, but also it's maximum discharge rate and thermal characteristics under load; as in, larger capacity isn't always better in some use cases.
It sounds like he saw one specification sheet of the new upcoming product, and generalized it to every battery in that size. A quick Google Search (tm) did not yield any useful statements on such.
I personally assume that the grade of battery used in the Model 3 battery packs is going to be similar to the lowest grade used in the Model S, but with lower available engine torque to compensate for the smaller overall battery pack size.
> A 18650 is a size and voltage specification. As in, it's like calling a battery a AA or AAA: any AA or AAA fits into a device and makes it run, but some AAs and AAAs last a lot longer than other batteries in flat out runtime, or survive usage in abusive devices, or in extreme weather conditions, or so forth.
18650 doesn't mean anything other than a cylinder 18mm diameter by 65mm long; it doesn't imply a certain voltage or anything else. I've worked with 18650s that have voltages from 2V to 4.4V. Nonrechargeable 18650s, though quite rare, exist at even lower or higher voltages.
I've got access to several spec sheets from Panasonic, who Tesla is pairing with, in combination with public spec sheets from existing 21700 cells. My guesses at Tesla's final 21700 battery specs are a combination of these spec sheets, my own knowledge about batteries, and some physical limitations (e.x. the theoretical max power density shrinks as the cell grows, and 21700s are roughly 50% more volume than 18650s.)
> There are low grade 18650s just as there are high grade 18650s. Maximum capacity isn't the only way to measure a battery, but also it's maximum discharge rate and thermal characteristics under load; as in, larger capacity isn't always better in some use cases.
Yep, that's why I addressed those things in my comment. Thermal issues are particularly interesting with Tesla's packs.
I don't want to specially handle my car every day. The car is good for in-city usage, but if you're travelling a lot and live in Europe, it's still long from being usable.
EDIT: an explanation of the downvotes would be nice.
Is it? A friend has had a few Model S's since launch in the UK (currently a 90D) and due to business interests all over the country covers well over 20K miles per year. We live in a rural area in the midlands, FWIW.
I know it's anecdata but his usage has convinced me that electric cars are far more capable and practical than some give them credit for.
I'm not sure why you are getting downvoted so bad. It's a fair point to bring up when people bring up these 500+ mile range runs. The Tesla is restricted to being an amazing city car, and that's OK.
Even if you're in the US and you live in a remote location, the car is crap for road trips. For example, you live in Rock Springs, WY and want to drive to Buffalo, WY. You will be lucky to make it on one charge and adding a supercharger to the route will take you hours out of the way.
Probably because it fits an unhelpful pattern of comments on a variety of new products or devices, namely: "this doesn't fit my needs exactly, therefore it is stupid/wrong/evil/crap".
It's perfectly possible to express these kind of opinions in a way that wouldn't seem confrontational but apparently that's hard for people to do. (e.g. "my town is quite hilly, so cycling doesn't make as much sense for me as it does in flatter areas") In this case, possibly just leaving off the first sentence would have been enough. Probably not though, as it still comes off like the world revolves around their, not particularly common, use case.
That's maybe half of it, the fact that their comment is quite possibly just factually wrong, combined with the above means they don't get the benefit of the doubt.
There's lots of previous-gen EVs that would probably welcome the label of "good for in-city use", but it seems a stretch to say that is the limited application for any model of Tesla S.
Not sure personally, the poster says it's good for X case, for Y case it's not so good. Doesn't really fit the pattern you're outlining, he hasn't called Tesla cars bad at all.
I'm not seeing the confrontation, I'm seeing concessions made and a balanced comment.
I think that's implied by the first sentence: "I don't want to specially handle my car every day", which seems like a claim that you need to do that with Teslas. Which is only true if you want to travel 5 or 600 miles on one charge every single day, which basically nobody does.
Y'all pretend like there's nothing between a city car and a car that regularly does 500+ mile trips. EV's aren't at the point where really long trips are as convenient as in a combustion car, that's not news. But the range that they're good for has been steadily increasing, and so have the goalposts of the "I'll buy one when they can do XYZ miles on a single charge" comments.
This discussion has been had so many times, I can't blame people for downvoting it. Nothing new is going to come of having it again, it's just going to derail the thread.
Part of why the goalposts changed is most people don't know what the goalposts should be.
When I first heard of electric cars they were convert your car with lead acid batteries. An interesting project, but not practical. Then the EV1, but since I don't live in California I ignored it. Then Tesla which was neat, but I make 300 mile (one way) trips and the supercharger was still a promise - the price made it a "I could make it work if there was a supercharger along my way, but it is too expensive". Then came the leaf - affordable, but the range was such that I didn't have confidence I could go to work, lunch and get back home again. Now the leaf has solve the above, but I'm learning about battery life - it can work for the first 60,000 miles, but after that replace the battery at a high cost.
What will be the next goalpost? I don't know. The number one goalpost for me is always is it cheaper to replace my car or not. The reality is my current car is still working (though we will see what my mechanic says, there are some signs that the body is starting to fail), and at 40+mpg electric is not a better deal than keeping it working.
But the comment was in response to a comment about a 550 mile record. I think that brings fair game to point out that nobody can reliably use the thing to perform trips 85% that long frequently. For example, someone who classifies as a "mega-commuter"[1] would not be able to use a Tesla unless their office has a charging station.
The percentage of the population that has these 'mega-commutes' is insignificant in the grand scheme of things. Bringing it up as an argument about why EVs are 'long from being usable' is why they are getting down-voted.
Maybe they're being downvoted because their comment was irrelevant and useless. "This could do X if you do everything just right." "I don't wanna!" Well, great. They didn't say people should, or that it was practical. They just said it would be possible. At no point did that comment state or imply that the hypermile range was in any way realistic or useful.
The range unfortunately isn't that large because of generally colder weather. Charging stations aren't on the way, and not even a quick detour, but a significant change of the way. When I'm going 1200 km to a client (or visit my parents), I don't have the time to go to the charger and charge my car three times, but it's no more than 10-hour trip with a conventionally-powered vehicle.
If the route has Superchargers, your 10-hour trip in a conventional vehicle might be a 12-hour trip in a Tesla. Longer, but not horribly so. It depends on how you drive, too. If your 10-hour trip involves running into the bathroom and eating at the wheel, the penalty will be larger. If you sit down for meals and take breaks anyway, the penalty can be almost zero.
Some people buy don't buy a small car because they might need to haul a sofa around town once a year. Other people don't buy a car with limited range because they might need to drive more than 4 hours without a long break once a year.
Statistically, I move every three year so far. I do have a lot of stuff though, last time it took half a shipping container for everything. If I extend your logics for my case, I should be driving a container truck every day.
We shouldn't optimize for the exceptional cases. It's far cheaper and easier to think of the main usage first and deal with the exceptions when the time comes. Renting a shipping container once every few years is not that expensive.
I agree with you. I didn't give any logical argument, I just presented how people seem to behave, for better or worse. I don't own a car and when I need one it's usually one of the two scenarios I outline -- in which case I rent one.
> Other people don't buy a car with limited range because they might need to drive more than 4 hours without a long break once a year.
This is an easy argument to make, and I've made it myself in other cases, but there are two parts to the equation. The first is how often you might need to travel a long distance, but the second is what the consequence might be if you can't.
Personally speaking (this thankfully hasn't happened often) I've had to make literally last minute 12 hour drives to attend to gravely ill relatives. If our only car had been a 300 mile range electric, those drives wouldn't have been possible in anything close to the same duration. (Looking for an alternative/rent car at 11PM isn't really an option. Looking for a Supercharger station in rural Virgina at 3AM even less so.)
There's a third part to the equation: how often your trip is one which can't use Superchargers.
Most trips can. Coverage is pretty good nowadays. You don't "look for" them, the car tells you where to go. 3AM is irrelevant, they're open 24/7. If your trip is well covered by the network, you're looking at a 10-20% time penalty. If it's not, you're screwed, of course, but people seem to overstate how likely that is.
Running the route I'm describing through a trip trip planning website, the travel time goes from 11:12 (h:m) to 15:52 (3:53 charging)... so more like a 40% penalty. In my particular scenario, it would have translated into 4-5 hours of (minor) detours and waiting at Supercharger stations in the middle of the night with sick family waiting. For me, personally, the flexibility to avoid that kind of delay is something I've found valuable at particularly important moments of my life.
Aside from the fact there are fewer Supercharger stations, some of this is just an inherent limitation of the technology. Even a Supercharger station (145KW) is slightly more than two orders of magnitude less capable of transferring energy than a gas station pump (16MW). Even if the battery technology got to the point it could handle that level of power transfer, I'd hate to be anywhere near a 16MW electrical charging station. (>2K amps at 7,200 V, not to mention the required >100MW feed INTO something like an 8 car station with that capacity per car.)
This makes me wonder about the idea of swapping out battery packs. It seems like that could possibly be made just as fast as filling up on gas.
Can you give the approximate route? Just curious what this particular scenario looks like.
Of course the limited charging speed has an effect, but it's not gigantic, especially if you're going to be taking breaks anyway. If you're not taking breaks, the effect is larger.
I'm not trying to tell you not to care about this, mind! I see a lot of people thinking it's worse than it is, saying long trips require extreme patience, etc. Having done many thousand of miles of long trips in my car, it's not bad at all. But certainly there are cases where it really is just too much, and as long as the facts are out there, I don't mean to try to convince you to alter your priorities.
As far as battery swapping goes, Tesla did develop this, and built a station in between LA and SF. They originally showcased it as being twice as fast as filling up a tank of gas, but that was before they added the titanium shield under the battery, so the version they put into operation was more similar to gas filling time. It never got very popular, partly because it was expensive, partly because they never pushed it, and partly because most people didn't mind the Supercharger stops. I'm not sure if the station is still in operation or not, but it'll probably remain the only one.
To be honest, I thought the Supercharger coverage along the route was excellent. I don't know what the individual sites are like (ie: would I really want to hang around an hour or two), but the spacing and locations looked really quite good.
> If you're not taking breaks, the effect is larger.
Yeah... we usually do take breaks. (Without breaks, it's a doable drive, but not easy.) A supercharger station in the middle of a cluster of restaurants would be a good opportunity for cross-sales, etc.
> I'm not trying to tell you not to care about this, mind!
Understood. To tell the truth, I don't think this specific use case is necessarily a huge deal. Even though it did impact us, it's a low priority event.
> As far as battery swapping goes, Tesla did develop this,
Interesting. Based on what the article was saying about the battery's interface to the car, it didn't seem like a quickly swappable component.
Are the supercharger stations usually staffed with people to assist? I'd thought they were self-service. It may be that the reason they haven't pursued the battery swap idea more aggressively is that it requires more staff at supercharger stations, as well as all the logistics around keeping a stock of pre-charged batteries at all the stations where you can do the swap.
One other comment I should make here is that despite what it might seeem I generally am very positive about electric cars. This is true, both as a means of of transport, as well as a way to (potentially) manage the electrical grid's use of solar/wind/etc. power. (Power sources that might not be as continuously reliable as something like a Natgas plant, etc.)
I tossed that route into evtripplanner.com and got results similar to what you describe. However, it doesn't seem to be planning all that well for some reason, because it's making unnecessary stops that add time, and skipping stops that reduce overall time. In particular, it's adding a stop at Newark, DE when a 100% charge could easily take you straight to Woodbridge, VA (there's no advantage to stopping early for the first stop), it's adding a stop in Atlanta itself (which may be necessary if you can't charge overnight there), and skipping a stop in Richmond which cuts down on total trip time when added. Fixing those up, I get a total trip time of 15:05, which is 3:14 more than what Google Maps shows for driving directly. That's about 27%, so still a bit over what I said.
Of course, it'll depend on what you're driving, too! I got those numbers by having it route for a Model S 85 (which is what I have, so that's what it was set to). If I switch it to a P100D and optimize from there, the total trip time is only 13:55. It doesn't have a 100D yet, but that should be even faster, since the non-P versions are a bit more efficient.
Which is to say, if you want to make trips like this faster, the bigger battery helps a lot. Applying some human smarts can optimize things. And it's definitely not the "hop in and go" you can do with a gasoline car. It takes some planning.
Regarding the locations, they're usually pretty good. Most of them are in commercial areas with places to have a meal, grab a snack, or whatever. Not always, though. The West Palm Beach location sticks out at me as particularly bad, being located at a Tesla service center in a pretty industrial area. I'd try to avoid that one next time I make that trip. This is another area where planning helps.
I'm not sure what you're referring to in the article that made it look like the battery wasn't easily swappable. It does talk about doing complicated things to change out the connector, but that's for a hypothetical swap of this new 100 battery into an older car. Tesla apparently changed the connectors at some point, so you'd need to do some work for that. But that wouldn't affect a battery swap station, where you'd presumably have a stock of batteries appropriate for your particular car.
You're right that supercharger stations aren't usually staffed. I have heard that some really busy ones sometimes have people helping organize, but that's rare. Mostly there would be no point in having anyone around. I think the goal was to have the battery swap stations be totally automated, but they never actually got to that point. There would definitely be a huge amount of logistics management and capital expenditure compared to supercharger stations either way. Even if it had caught on, I think swap stations would only have been on really busy corridors like LA to SF, or I-95.
I think the main issue is just that charging technology is good enough for enough people already, and is improving quickly enough. As you can see from the trip times above, the newer batteries already offer a pretty big improvement there, and hopefully there will be more to come.
At least one or two of the calls were quite urgent - We got the call late in the evening and were in the car within an hour or two.
Flying would've meant booking a last minute flight, waiting for whatever flight time, getting to the airport an hour or two in advance, landing at our destination, arranging transport, and then taking a two hour trip by ground transport. There was so much in the way of overhead and transition costs it didn't make sense. (Amtrak had the same problem.... we've tried that before too, but only once.)
Two 40 minute charges add 80% battery life and cover that distance assuming you start from a full charge. 750 miles is likely to take two refills on a gas car which take 5 minutes and you need to locate a station. So, the tech adds 1h 10 minutes over a 10+h trip, it's the infrastructure that's an issue for you.
PS: It's not really safe to drive 10h without taking a few breaks. But, I know the appeal.
They need to add a few more stations. On the 300 mile trip I take most often there is exactly one, and it isn't in the town we normally stop to eat at. (we commonly leave right after work and have supper 2 hours down the road which is a good time for a break). There is no station anywhere any of the hotels I stay at either.
In short, the current superchargers are a good start, but if they want to make electric cars work for long distance they need to have them at every restaurant in the country, and every hotel needs to provide a charging station.
In most of the country you can find a gas station every 20 miles even in the least populated parts. (though I can name some areas where next gas is 60 miles) Since a fill up is only 5 minutes I can fill up and then go to the restaurant across the street. With fillups taking 40 minutes we need the charging station to have a different model from current gas stations: they need to be places where humans would want to stop for a long time. Parks, hotels, restaurants, museums and the line come to mind.
It will be interesting to see what happens as (if) electric cars become common.
The supercharger network is pretty decent in central Europe, I don't see any restrictions for long distance travel there. And the range of over 300 miles makes it certanly a good car even for long distance travels.
I live in the French alps and from time to time I see Teslas in ski resorts - these cars are sometimes coming from far away. The furthest away one was from Denmark.
The poster is making a valid point, in that it lacks range without long breaks dotted about. This isn't a Tesla dealership, this is a discussion forum.
Nobody posited that the Tesla 100 KWh battery is all the range anyone will ever need. Just that it was pretty impressive (implying that it will cover many people's use cases, i.e. people who don't regularly drive 1200km in one go).
I might just be tired of seeing this exact same discussion on HN over and over again. I was hoping to see discussion on the battery tech, not a discussion about how big of a bikeshed we need. The range anxiety discussion has been beaten to death. It's not insightful. I can read the exact same comments on YouTube.
And you know, I want to talk about the recharge times further with you, but I'm not going to get the chance to do it if we're shutting down discussion.
Is that 40 minutes with the Tesla specific gear for charging?
Yes. Tesla has created a network of the so-called SuperChargers, which allow to charge with up to 120kW. So recharge times of 30-40 minutes for a leg of 200-300 miles are possible. Typically SuperChargers are placed on the main roads in less than 200 miles distance. You can find a nice overview of the network here: https://supercharge.info
I wonder if there is any potential danger to having a public Bitcoin wallet string. I don't know if you can "receive bad money" for example. I don't know.
"Coins" aren't a thing, so there's nothing to be tainted, per-se. However, yes - if an address that ordered a murder sends you a lot of btc, expect someone to come by and discuss it.
Also, the waters are muddied now (intentionally), in a similar way to how every piece of American cash is rumored to have traces of cocaine on it. The theory is that the more this implicates everyone, the less it implicates anyone.
I briefly searched on it, the one thing they mentioned was the possibility of being able to link exchanges to other unknown people because you're now known if your website says who you are and you have a key right there. But they also said to use other ones for each transaction. I don't know. Anyway thanks for the info. Bitcoin is a bit volatile for me but I appreciate it's capability and would like to have some in the future. I'm also broke/in a lot of debt so any concept of savings... Anyway I'm trying to "spread out my money" so to speak for a safety net. I don't know.
If you're in debt, you need to pay off your highest-interest creditor first, and then on to the next one. When you have spare money, you can hedge bets on investing it.
But, Bitcoin is not an investment.
First, nothing you don't understand is ever an investment for you. If you don't know mining and I do, I'm investing by buying shares in a mine whereas you're gambling by doing it. (For instance, if you don't know, and really understand, why bitcoin tends to be used in a manner where you empty the balance from one address, sending some to the intended recipient, and the leftovers to yourself at a new address, then you're not ready to invest.)
Second, it functions as a store of wealth not capital. Its gains are partly from other currencies devaluing around it, not it being used to create more goods the way buying a piece of capital (shares in a manufacturing company) would.
That said, if you do any gambling (lottery tickets) you might as well put that into bitcoin, you at least might get something back.
Yeah it wasn't so much "looking to grow" just that it would be separate from cash, another means of having money like items that have good resale value like Apple computers or something (like a MacBook Air for instance that even after 3 years later still sells over $600.00)
Yeah I briefly read about mining and how it's not worth it anymore unless you join a group to mine with.
I don't know, I'm not even able to open up bank accounts anymore/at the moment so I have different accounts whether prepaid or through job provided bank accounts or PayPal business account.
In that case, where you don't have false goals of runaway success or anything, and aren't gambling the farm on it, yeah you should throw a few bucks into it. If you read up on what the differences between currencies are and how that's likely to impact survivability, you'll be able to pick fairly well.
BTC, Ethereum, and Monero look good, but do your own research. Scams abound.
The most critical thing to remember is that if your currency is "in an exchange" it might as well not be yours. Funds only become yours, meaningfully, when transferred to an address whose keys you generated and which have never been online on an insecure device.
Ideally repurpose an old phone for a wallet and keep it in airplane mode. You can browse the chain with your regular phone, including monitoring incoming transactions, all you won't be able to do is sign an outgoing transaction. Then you either turn on the wallet-phone's connection when it's safe, or implement a paper-wallet system between the online and wallet phones.
That's overkill for what you'll probably put in right away, but good practice.
I have seen things that extrapolate out battery progress, so if batteries become cheaper/lighter/more powerful in a similar way they have in the past then that has a big impact on EVs, dropping their price and/or increasing their range.
But a lot of things seem fairly simple, if not obvious except with hindsight e.g. heated steering wheels and seats instead of air heating, heat pumps rather than resistive heating, puncture resistant tyres rather than carry a spare, led lighting, replacing side mirrors with cameras for lower drag etc. How much can straightforward, no new tech, improvements in all these areas actually help if you add them up?