June 20th Speculation

[Palpatine]

The reality is that most Tesla owners will rarely use any of this.
With a 200-300 mile range and most people driving less than 30 miles per day, then the number of times per year is likely less than 10 that you use either a Supercharger or Battery Swap.
So if it is a system that we rarely use, which option is a customer likely to pick during a road trip? Free or Pay for use?

I live in Seattle. The 3 Superchargers near me are:
1) Centralia WA (85 miles south) if I am heading to Portland
2) Burlington WA (65 miles north) if I am heading to San Juan Islands or Vancouver BC
3) Ellensburg WA (107 miles west) if I am heading for Spokane WA or towards Boise Idaho.

The number of times I am likely to use any of those is likely 2 or 3 trips per year maximum. 99% of the time I will be recharging at home and never using any of the recharging provided by any 3rd party.
20 minutes for a recharge to get back to 80% is perfect on a trip to anywhere around me. I don't anticipate any business case at all where it would make sense to pay anything for a battery swap.

I don't even anticipate that I will ever pay $0.50 or $1.00 for one of those silly Blink chargers or any of the other level 2 chargers around here.
Why on earth would we need it when I have a 85 kwh battery pack? I never needed those when I had a Roadster with a 200 mile range (Standard mode).

Even if a battery swap was entirely free, I consider that the less desirable solution due to the risk of the battery swap turning my car into a brick due to an error in the system.
It is not something that I would pay in advance for, nor is it something that I would pay per use, especially if there is a Supercharger in exactly the same location for free.

Is anyone trying to make the argument that a Battery Swap location won't also have a free Supercharger placed in the same location?
When faced with the options of:
a) Battery swap for a fee
b) Supercharger for free
Which would you choose in that scenario? I am a fairly wealthy guy. But I am going to pick the Supercharger every time in that scenario. No question about it.

I think a lot of people would make exactly the same choice. So if this June 20th announcement is really battery swap, then that plan has to be competitive with the Supercharger.
All Superchargers are already free for 85 kwh owners. And I think many 60 kwh owners also paid the $2,000 fee for the access.

If there is another charge for a battery swap option, I expect very few owners to purchase it. Tesla will be paying for that network on their own. And I expect very little utilization of it.
The most I would expect for June 20th, if it is battery swap news, is that they are doing a test battery swap station to see if customers are interested.

 

[stopcrazypp]

If Tesla is spending any significant CAPEX on a bunch of battery swap stations...the company is going out of business.

I don't know why you keep equating battery swap with the company going out of business. Tesla is setting out $25 million for 100 supercharger stations. Tesla can spend the same amount to build 25-50 swap stations assuming $500k-$1 million each (they don't need to be as dense since you can get ~230 miles of range per swap compared to ~130 miles in 20 minutes for the newer 120kW superchargers). Tesla is targeting $350 million in profits per year just for the Model S line. This is not going to bankrupt the company (if it is then Tesla has more serious problems than anything to do with either possible networks).

After Better Place, the burden of proof will be on Tesla Motors to prove this won't take the company under. As if Tesla Motors needs to give others more ammunition about EVs. Adding a huge battery swap business expense to the balance sheet just a few weeks after Better Place went under, that would be monumentally retarded of the brain trust at Tesla.

Fisker went bankrupt, and plenty of other plug-in/EV companies went bankrupt but that does not necessarily mean Tesla will go bankrupt. And those are examples that actually are relevant. Better Place was an infrastructure company, not a car company. They went under because they build infrastructure (not just swap, but also charging networks) when there were no cars. Tesla is different: Tesla is building cars and the network is a just a marketing expense. At worse it leads to a temporary drop in the stock price, but in the long run a battery swap is going to help address mass consumer appeal (esp. for Gen III) and that will help those with long positions.

That is why I don't think there is any chance of a battery swap network being announced June 20th. I think at best Tesla might demo a battery swap. Then they might announce one location they are going to run a trial test at to see if customers use it. If there is no customer interest in the concept, they will let the idea die as it deserves to die.

I also don't think it'll be a swap network announcement (as in one that is in progress already) since there's no evidence Tesla is in the process of building one right now. At best it'll be an announcement they might start building one. But I say the chance of a demo of a battery swap is pretty big.

 

[Palpatine]

but in the long run a battery swap is going to help address mass consumer appeal (esp. for Gen III) and that will help those with long positions.

Gen III customers are even less likely than Model S customers to pay extra for a battery swap subscription, or option, or however Tesla plans to bill for this.
Those customers are more cost sensitive than Model S owners.

 

[Yggdrasill]

I still mainly struggle with the utility of routine swapping if I have a 350 or 400 mile pack (like in 3-5 years). There are a lot of good points for the swap concept, but seriously how often do you drive 400miles and will need swap capability to save the extra 30mins to hour needed for supercharging (assuming 85 pack and 120kwh charging)?

Like I mentioned before, I think the battery swap system is superior when it comes to power-hungry usage. If you cruise down the autobahn at 100 mph with five people and a bunch of luggage in he car, running the AC, you'll be lucky if the Model S lasts 100 miles/1 hour. And a Model X towing a boat or something will also probably not go much further than 100 miles. I see the battery swapping as supplementing the superchargers, not replacing them. On usual trips, even long trips, SC will be sufficient. But there are circumstances where it is less than ideal. For the autobahn example - people don't want to stop to charge for 20 minutes every 30 minutes, and they don't want to slow down either.

 

[CapitalistOppressor]

The reality is that most Tesla owners will rarely use any of this.
With a 200-300 mile range and most people driving less than 30 miles per day, then the number of times per year is likely less than 10 that you use either a Supercharger or Battery Swap.
So if it is a system that we rarely use, which option is a customer likely to pick during a road trip? Free or Pay for use?

This is absolutely true. For my models I tend to use these systems 9 times per year, and that is generous. Only 2.5% of vehicle daily trips are greater than 50 miles, so even using 9 is assuming that all of these trips require a recharge(or swap). The truth is that the average number of day trips using these systems is probably closer to 4-6.

(an interesting note is that while folks on average only spend ~9 days driving more than 50 miles, the total miles driven on those days accounts for something like 20% of total miles)

- - - Updated - - -

Gen III customers are even less likely than Model S customers to pay extra for a battery swap subscription, or option, or however Tesla plans to bill for this.
Those customers are more cost sensitive than Model S owners.

Yes, this is true, but at the same time, Model S customers are going to be able to build a lot of the basic infrastructure. The marginal cost over the basic infrastructure (especially in the case of swapping) is the extra battery storage required. The Gen III battery will cost under $10k, so the marginal cost for the highway infrastructure is ~$500 per car, which is only ~1.25% of the likely $40k entry level cost of Gen III (and less for more expensive versions).

 

[eAdopter]

@Palpatine +2

I don't know what the announcement will be, but I think the battery swap idea is a non-starter for the current generation of cars. I can't think of a single justification that trumps a fast charge.

My guess is an announcement regarding faster charging for the reasons Palpatine stated, plus many more.

Who needs the risks and expense of a battery swap if a 15-minute charge is available? I think Elon is smarter than that.

 

[Johan]

I really don't get how some of you all of a sudden think that a super-supercharge all of a sudden is going to be available, just because you feel that swapping has a poor business case? Look, even if supercharging could scale up to 240kW (with added/different connector) or even more than that (480kW?) there is no way that kind of charging rate can be tolerated all the way to 100% SOC! We know that the upgrade from 90-120kW also means that they are tapering of later, but there have been no suggestions at all that tapering off towards the end of the charge is something we can all of a sudden do away with.

Remeber, the wording from Tesla has been pretty clear: A full battery in less time than it takes to fill a tank of gas. I know that the time to fill a tank of gas is debatable. The full battery however is not. It means full. And the way I see it only swapping your battery to another battery, which has been pre-charged, can accomplish that at this point in time.

 

[gameon]

I really don't get how some of you all of a sudden think that a super-supercharge all of a sudden is going to be available, just because you feel that swapping has a poor business case? Look, even if supercharging could scale up to 240kW (with added/different connector) or even more than that (480kW?) there is no way that kind of charging rate can be tolerated all the way to 100% SOC! We know that the upgrade from 90-120kW also means that they are tapering of later, but there have been no suggestions at all that tapering off towards the end of the charge is something we can all of a sudden do away with.

Remeber, the wording from Tesla has been pretty clear: A full battery in less time than it takes to fill a tank of gas. I know that the time to fill a tank of gas is debatable. The full battery however is not. It means full. And the way I see it only swapping your battery to another battery, which has been pre-charged, can accomplish that at this point in time.

agree with you on this. I don't think tesla can develop super super charger all of a sudden. It has to be battery swap and that's not big news because people don't take 300 to 500 miles trip every month (maybe 2 or 3 times). I am not counting road warriors who travel a lot (also you won't tesla taxi anytime...hehehe)

 

[CapitalistOppressor]

@Palpatine +2

I don't know what the announcement will be, but I think the battery swap idea is a non-starter for the current generation of cars. I can't think of a single justification that trumps a fast charge.

My guess is an announcement regarding faster charging for the reasons Palpatine stated, plus many more.

Who needs the risks and expense of a battery swap if a 15-minute charge is available? I think Elon is smarter than that.

Charging this fast with the existing connecters is probably impossible even on the 60kWh car, even assuming you are willing to risk substantial degradation to the battery. It requires 240kW of throughput, and assumes no tapering to charge the 60kWh car to full that quickly, and the connecters just don't seem able to support that load. And of course the 85kWh car would take longer, and its equally improbable.

Charging faster than 240kW is even worse from a feasibility standpoint.

Maybe in a few years 240kWh might be possible, but regardless of how you want to implement it you need large scale grid storage.

A typical house uses something like ~50kWh per day, or about 1kWh per half hour on average. So just one car charging on this futuristic 240kW SuperCharger will take up the average consumption of ~240 residential homes. Thinking that you can scale that in any reasonable way (or even 120kW SuperChargers), with millions of cars on the road, just doesn't work unless you have large scale power generation right on site.

That means large grid storage placed on site to store the necessary power. Given that cost, the marginal cost of swapping vs SuperCharging is quite small. And even 240kW SuperCharging is a LOT slower than swapping, and not possible for current batteries. Swapping makes a lot of sense and will scale nicely (and inexpensively) into the next decade when maybe 480kW (or faster) charging becomes possible. Regardless, with effective swapping you are not dependent on speculative battery innovations.

You can move forward with existing Li-Ion technology and get better speed and economics than you can get with ICE. Right now.

 

[c041v]

agree with you on this. I don't think tesla can develop super super charger all of a sudden. It has to be battery swap and that's not big news because people don't take 300 to 500 miles trip every month (maybe 2 or 3 times). I am not counting road warriors who travel a lot (also you won't tesla taxi anytime...hehehe)

That last line made me wonder, is their a future commercial application that would perhaps builds a stronger business case for swapping? Somebody commented a few pages back that this may just be a marketing opportunity for Tesla to quell the range anxiety arguement for road trips but, if there are plans for a pick up truck or perhaps light commercial version of the Gen III platform in the not so distant future, this is perhaps an arguement for the swapping vs. free supercharger debate, especially if the swapping mechanism is franchised.

A possible scenario could be a construction site where pick ups see little down time, and there is a tremendous costs to keeping them fuelled. I once worked on a project where we built our own fuel farm just to keep the fleet of trucks close to cheaper, bulk fuel supply. This was in a large city, the project collectively had several hundred pick ups and the company has many thousands in North America.

It's out there, but I am having trouble seeing how swapping alone could be the biggest announcement given some of palpatine's arguements and the proposed coverage of the supercharger network.

edit: part of what got me thinking that there's a commercial aspect that being overlooked is that the Ford has a special colour for this company that is applied right at the factory. There's something to be said about building a business case for customers that buy vehicles by the thousand.

 

[WarpedOne]

Tesla is setting out $25 million for 100 supercharger stations. Tesla can spend the same amount to build 25-50 swap stations assuming $500k-$1 million each (they don't need to be as dense since you can get ~230 miles of range per swap compared to ~130 miles in 20 minutes for the newer 120kW superchargers).

Now go and say it out loud that 50 swapstations add more value to EV owners than 100 supercharger locations do.
Which option enables more people for long distance travel?
Problem lies in availability of fast-charging and not in its exact speed. GO into another thread where people are bitching about Chademo stations that are everywhere but they cannot use them.

Yes, swapping offers a bit faster "charging" but it is available to much less drivers for the same money spent.
There is just no way that SS could be cheaper than SC, that is why building a nationwide SS network is very poor use of money.
Is this really that hard to grasp?

Relying on Elon having some grasp on financials, I bet there won't be such a network. SS will be rare and far between. Similar to service centers.

Fleets are other story altogether. For them SS makes much more sense than SC. Buy 100 Tesla vehicles and Tesla offers you a managed SS at your location.

 

[deonb]

The reality is that most Tesla owners will rarely use any of this.
With a 200-300 mile range and most people driving less than 30 miles per day, then the number of times per year is likely less than 10 that you use either a Supercharger or Battery Swap.

-and-

This is absolutely true. For my models I tend to use these systems 9 times per year, and that is generous. Only 2.5% of vehicle daily trips are greater than 50 miles, so even using 9 is assuming that all of these trips require a recharge(or swap). The truth is that the average number of day trips using these systems is probably closer to 4-6.

Not quite. Only 2.5% of trip count is over 50 miles, and 1% over 100 miles. But 15% of trip distance is over 100 miles:
http://www.fhwa.dot.gov/policyinformation/pubs/pl08021/fig4_5.cfm

These are your SuperCharger-eligible trips.

We also know the average driving distance per year for men is 16'550:
http://www.fhwa.dot.gov/ohim/onh00/bar8.htm

So 15% of 16550 is 2482 average supercharger miles per year. You get on average 120 miles between superchargers, so that makes it closer to 20 SuperCharger stops per year.

Sometimes you're going to have less than 120 before you get to a SuperCharger (the ones close to your home & destination), but sometimes you'll also skip them.

Remeber, the wording from Tesla has been pretty clear: A full battery in less time than it takes to fill a tank of gas. I know that the time to fill a tank of gas is debatable. The full battery however is not. It means full. And the way I see it only swapping your battery to another battery, which has been pre-charged, can accomplish that at this point in time.

Can you provide a quote or any other evidence of that?

And by a full battery do you mean range charged? How would you be providing that even in a battery swapping scenario at a location in Nevada? Big air conditioners keeping the batteries at range charge 100% per year in case someone stops by?

 

[cb32000]

If you swap the battery in the Model S what happens to the coolant and how do you prevent coolant leaks on an automated system?

 

[TeslaRumors]

Treating whole battery pack as smaller individual battery packs

This may be far-fetched, but here goes....
The invitation and Elon's twitter comment says: "There's a way for a Model S to be recharged faster than you could fill a tank of gas"

Clearly it has nothing to do with any car, Gen X or Tesla X. It specifically is referring to the amount of time it takes to charge, that is, relative to the amount of time it takes to fill an ICE tank with gasoline. So I came up with this concept/theory.

What if an 85kwh was treated as multiple individual batteries instead of just 1 large one? For example, If I were to go to a supercharger location that had 10 superchargers, and split my battery up into 10 parts and gave each individual supercharger that task of supercharging each 8.5kwh battery component (85kwh/10=8.5kwh), then my battery would be charged 10 times faster, because 10 different superchargers are handling the job.

Elon also said that there was something "right under our nose". What if in the electronics of the Model S, there already exists technology that treats the entire 85kwh or 60kwh battery as individual smaller components and delivers a simultaneous individual charge to each to expedite the charge?

I'm not an electrical engineer so this is purely hypothetical and could not make sense to someone who is in fact an electrical engineer. However, I suppose if a single Supercharger, could act like 10 superchargers and deliver enough power to each battery subset, then it would be possible to supercharge the entire 85kwh battery pack in 2 minutes instead of 20 minutes.

 

[Yggdrasill]

Can you provide a quote or any other evidence of that?

Everything we know about current li-ion cells suggest they can't be charged substantially faster than 120 kW on a 85 kWh pack. You might be able to increase the speed for the first half of the charge cycle by some amount, but current cells will not achieve 100% in 10 minutes. For that you need a different chemistry, like the lithium-titanate SCiB.

And by a full battery do you mean range charged? How would you be providing that even in a battery swapping scenario at a location in Nevada? Big air conditioners keeping the batteries at range charge 100% per year in case someone stops by?

This is fairly easy. You merely keep the batteries at as low a percentage as possible while still being able to fully charge a battery before the battery of the customer's car is removed and ready to receive it's battery.

So, if you have 10 batteries in a battery swap station, it takes 10 minutes to swap a battery, you can charge each battery at 20 kW above 50% SOC and 120 kW below 50% SOC, and it takes 5 minutes from the battery swap procedure is initiated to the car being ready to receive it's new battery, you have:

- One battery at 98% SOC. The remaining 2% is charged in the five minutes before the battery needs to be removed from it's bay.
- One battery at 94% SOC. By the time the battery swap is completed, this battery has been charged to 98% and is ready for the next customer.
- One battery at 90% SOC. By the time the battery swap is completed, this battery has been charged to 94%.
- One battery at 86% SOC. By the time the battery swap is completed, this battery has been charged to 90%.
- One battery at 82% SOC. By the time the battery swap is completed, this battery has been charged to 86%.
- One battery at 78% SOC. By the time the battery swap is completed, this battery has been charged to 82%.
- One battery at 74% SOC. By the time the battery swap is completed, this battery has been charged to 78%.
- One battery at 70% SOC. By the time the battery swap is completed, this battery has been charged to 74%.
- One battery at 66% SOC. By the time the battery swap is completed, this battery has been charged to 70%.
- One battery at 62% SOC. By the time the battery swap is completed, this battery has been charged to 66%.

It becomes a bit more complicated if you need to take into account customer-owned batteries vs Tesla-owned batteries. Then, as the battery swap station receives customer-owned batteries, the swap station has fewer Tesla-owned batteries to work with, and it could run out of Tesla-owned batteries, which would mean it would need to close down and wait for a resupply. At the same time I would assume the customer-owned batteries would be removed and transported to a storage facility.

- - - Updated - - -

I'm not an electrical engineer so this is purely hypothetical and could not make sense to someone who is in fact an electrical engineer. However, I suppose if a single Supercharger, could act like 10 superchargers and deliver enough power to each battery subset, then it would be possible to supercharge the entire 85kwh battery pack in 2 minutes instead of 20 minutes.

It doesn't matter if you are charging a single cell or 7000 cells. It will take approximately as long to do so.

The limitation isn't in the supercharger, the limitation is in the chemistry of the NCA li-ion cells.

 

[deonb]

This may be far-fetched, but here goes....
The invitation and Elon's twitter comment says: "There's a way for a Model S to be recharged faster than you could fill a tank of gas"

Clearly it has nothing to do with any car, Gen X or Tesla X. It specifically is referring to the amount of time it takes to charge, that is, relative to the amount of time it takes to fill an ICE tank with gasoline. So I came up with this concept/theory.

What if an 85kwh was treated as multiple individual batteries instead of just 1 large one? For example, If I were to go to a supercharger location that had 10 superchargers, and split my battery up into 10 parts and gave each individual supercharger that task of supercharging each 8.5kwh battery component (85kwh/10=8.5kwh), then my battery would be charged 10 times faster, because 10 different superchargers are handling the job.

Elon also said that there was something "right under our nose". What if in the electronics of the Model S, there already exists technology that treats the entire 85kwh or 60kwh battery as individual smaller components and delivers a simultaneous individual charge to each to expedite the charge?

I'm not an electrical engineer so this is purely hypothetical and could not make sense to someone who is in fact an electrical engineer. However, I suppose if a single Supercharger, could act like 10 superchargers and deliver enough power to each battery subset, then it would be possible to supercharge the entire 85kwh battery pack in 2 minutes instead of 20 minutes.

Ok. Let's go further and break up the battery into 7200 individual batteries. (It already is today). And take the biggest charger in the world and connect it to one of those. Ok, so the battery explodes and now I'm covered in lithium and cobalt. New battery... ok, so let's make the charger a little bit smaller this time and look at how much the battery can handle.

Turns out that a Panasonic NCR18650A, which is what Tesla uses, has a maximum charge rate of 1C (3.1 Amps at 3.7V). It stores 3.1 Amp/Hours - or 0.011 kW/h. So at the factory rating, the individual cell will be overdriven if you charge it faster than 1 hour. Ok, so let's put in some active liquid cooling and have a complicated charge protocol to monitor it, and we also only charge the battery halfway up. Then we charge it at 1.5 times the factory specification and we do it in 20 minutes. That is what Tesla does today and it's an absolutely amazing feat of engineering as is.

To charge it in 2 minutes would require charging a NCR18650A at 15C, or 15 times the factory maximum specification (and 50 times the recommended specification). If you do this in 5 minutes instead, you're talking about 6C. That's a bit closer and you may be able to get away with that in a lab setting by cooling the battery with liquid nitrogen while you're charging it.

Super-cooled charging with an external coolant has actually been proposed earlier on this thread. As far as charge theories are concerned, it's one of the most realistic ones. But not simple by any means.

[Edit: My numbers originally on this was off by a factor of 2]

- - - Updated - - -

Everything we know about current li-ion cells suggest they can't be charged substantially faster than 120 kW on a 85 kWh pack. You might be able to increase the speed for the first half of the charge cycle by some amount, but current cells will not achieve 100% in 10 minutes. For that you need a different chemistry, like the lithium-titanate SCiB.

I know. I meant evidence to support the following statement - and specifically the 'full battery' part. (I've not seen wording from anybody that said 'full battery').

Remeber, the wording from Tesla has been pretty clear: A full battery in less time than it takes to fill a tank of gas.

And then:

- One battery at 98% SOC. The remaining 2% is charged in the five minutes before the battery needs to be removed from it's bay.

You can't store a battery at 98% SOC in 120 degree weather. Worst possible thing for the battery. Either have to store it at 80 to 90% SOC (which would refute Johan's "full battery" claim), or very actively cool it down.

 

[Yggdrasill]

Turns out that a Panasonic NCR18650A, which is what Tesla uses, has a maximum charge rate of 1C (3.1 Amps at 3.7V). It stores 3.1 Amp/Hours - or 0.011 kW/h. So at the factory rating, the individual cell will be overdriven if you charge it faster than 1 hour. Ok, so let's put in some active liquid cooling and have a complicated charge protocol to monitor it, and we also only charge the battery halfway up. Then we charge it at 3 times the factory specification and we do it in 20 minutes. That is what Tesla does today and it's an absolutely amazing feat of engineering as is.

Tesla does not charge at 3C, they charge at around 1.5C (50% in 20 minutes). This is pushing it relative to the specifications, but I'm sure they've done a lot of testing to ensure the battery doesn't take too much damage from it. You are correct it is very impressive.

 

[deonb]

Tesla does not charge at 3C, they charge at around 1.5C (50% in 20 minutes). This is pushing it relative to the specifications, but I'm sure they've done a lot of testing to ensure the battery doesn't take too much damage from it. You are correct it is very impressive.

Doh. Of course. Full charge in 40 minutes. (Theoretical, but can't actually do that).

I edited the post and divided everything by 2 . But still can't charge at 15 C.

 

[Yggdrasill]

You can't store a battery at 98% SOC in 120 degree weather. Worst possible thing for the battery. Either have to store it at 80 to 90% SOC (which would refute Johan's "full battery" claim), or very actively cool it down.

I assume each battery in the battery swap station will have the coolant lines connected to an AC unit. The battery can be kept fairly cool, and of course you are probably not talking about many hours between each swap, so you're only talking about an hour or two that the battery is kept at over 90% SOC. The degredation on each battery should be fairly equal, as the batteries are cycled through the different battery swap stations.

Furthermore, as we are probably not talking about free swapping, any extra degredation due to harsh treatment will merely be rolled into the price.

 

[deonb]

I assume each battery in the battery swap station will have the coolant lines connected to an AC unit. The battery can be kept fairly cool, and of course you are probably not talking about many hours between each swap, so you're only talking about an hour or two that the battery is kept at over 90% SOC. The degredation on each battery should be fairly equal, as the batteries are cycled through the different battery swap stations.

Furthermore, as we are probably not talking about free swapping, any extra degredation due to harsh treatment will merely be rolled into the price.

See my post (#250) on:
http://www.teslamotorsclub.com/show...ll-be-accomplished/page25?p=362836#post362836

We're already talking about $6000 per vehicle that needs to be recovered for swapping. At some point it just starts being too many things to roll into the price.

There will actually be many hours between swapping. If you make swap stations too dense (too many cars / swap station) you won't have enough power to feed them. A swap station (and SuperCharger for that matter) needs to run at an average of 6 swaps per day to be energy neutral with 200 solar panels.