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Swap Demo - Crowdsourced Projections

So it's official: we're on for a very exciting live demo Thursday. (Will be there for sure).

New battery swapping technology will let you add charge to you Model S in less time than gas.

Here's your chance to show your chops as a Tesla forum expert. Make your educated guesses at the following specs:

1. Capacity added per pack swap (kWH): 85, 60, 40 ... ?

2. Sub components per pack: 1, 2, 4 ...?

3 Weight of each component (lbs): 1,000, 200, 100, 40 .., ?

4. Swap hardware option cost: $2k, $1K, $500, free .... ?

5. Exchange fee per swap: $199, $99. $69 .... .?

6. Swap Locations: TM Service centers, SC's, TM Swap centers, existing retailers ... ?

Ply your wits and see how well the wisdom of the crowd predicts the results.

Winning prediction gets halo post.

1 100KWh
2 1
3 50
4 Free
5 40 USD
6 Supercharger locations

One more thing -

An Al Air pack that's 40lbs wet, is more like 15lbs dry.

Shipping those all over the country would be much less expensive than the equivalent capacity in LiIon, and less than 10% the capital cost.

And no self-discharge, or storage safety risks while dry on the shelf.

Virtually any retail site could stock it. Including a truck.

1. 60
2. 4
3. 40
4. $500
5. $49
6. Selected retailers

Here's my Wager

1. 125 Kw - Nearly 500 mile range

2. Perm or Temporary Replacement for Existing Pak

3. Nominal Added Weight

4. Free for Temporary Use (return date specified at exchange, may be limited time-frame, deposit required) $20K for upgrade from 85kw - $30K from 60kw

5. Free

6. TM Service Centers - Mobile Exchange System Like P.O.D.S. Moving System.

DouglasR wrote:
A $2,000 activation fee would completely undercut the $12,000 battery replacement option. You could wait until year eight, do a single swap for $2,000, and beat the replacement option price by $10,000. You are saying that, in addition to the swap at year eight, you get free swapping whenever you want it for only $2,000? Free electricity for life? Not gonna happen at that price. Maybe $15,000?

That makes more sense than just about anything else I have read about this.

There is simply no way for this to be free. The abuse of the system would obviously load up Tesla with a bunch of used batteries at some point in time.

Right before someone sells their car, they are going to go swap in a new 85 kwh battery pack. So clearly there has to be some protections involved or Tesla is going get hosed somewhere.

I am thinking this has to have at least an activation fee higher than $12,000. Or there needs to be some long term subscription contract where you pay that amount over time.

So when faced with that, explain to me why I wouldn't just use the free Supercharger at the same location? This doesn't seem like it is even a close call for saving 10-15 minutes.

1. Capacity added per pack swap (kWH): 85

2. Sub components per pack: ??? I guess 1

3 Weight of each component (lbs): whatever the battery pack weighs

4. Swap hardware option cost: over $12,000 or a subscription fee that comes out to about the same.

5. Exchange fee per swap: probably built into the fees for #4

6. Swap Locations: SC locations

My prediction on #2 is like for like. 1 part.

Mark K

I am 110% with you on the logical issues for the range pack. Elon is all about logic. Main pack swapping never made sense to me, but the more I think about it, the less sense it makes. In addition to the issues noted above, there is the whole issue of 60's vs 85's. Will 60's be able to swap for 85's? If so, this will piss off the 85's for spending the extra 10K for the extra range for trips. So no way Tesla allows this. Then either Tesla would have to do one of three things: 1)charge 10k to 60's for the privilige - nobody would do this. 2) Tesla would have to store both 60's and 85's at sc stations and somehow the robot would know to give a 60 to a 60 etc. This would be a logistical nightmare. 3)They insert software that limits the 60's to 60kwh even if it is 85kwh battery (like the 40's having a 60kwh pack). This may be more workable but still seems so improable and completely unlike Elon given all the other issues.

So could the range pack concept work without getting out of the car or opening the frunk? I think so, we just forget about the idea that the range pack goes in the frunk. Rather, could there be a hidden slot for a range pack in the existing battery casing. Interestingly, if you look at the main pack, it is completely flat except for a very nice rectangular structure (link to the picture below) that as Elon said is "right under your nose" and has been "there all along". So you simply drive up, a slot opens underneath the car and the range pack slides in - 30 seconds or less to without breaking a sweat. Beautiful!!!

Thus, this is my final (ha ha ha) predication: Al-Air battery that slides into the rectangular structure at the front of the battery casing. No main pack swapping.


Oops, here is the link for the picture of the main pack:

How about this: No activation fee, unlimited swaps at the cost of the electricity alone, or about $10 a pop.

BUT, the battery swapped in will be software limited so that the car can use only an amount of energy equal to (or perhaps slightly better than) that of the battery swapped out. This will be determined by measurement (TM can read the logs of your recent charge sessions, and should be able to determine the condition of your battery with reasonable precision) or, lacking that, based on age and mileage. In other words, for $10, you are getting the functional equivalent of a fill-up of your existing battery, no better, no worse.

The beauty of this approach is that you are not required to come up with a large sum of money to participate in the swapping process. At the end of eight years, you will have a battery that is (artificially) degraded to the same extent as if you had kept your car's original battery. If you want to purchase the battery replacement option at $12,000, this program would not undercut that option; the software limitations can simply be removed for those who purchase it. If, in the future, TM wants to offer a different battery renewal upgrade, they can do so. But whether or not you pay for some sort of upgrade path, the swap program would be available to you, and would be priced low enough that you might prefer to pay for the swap than to wait for a free supercharge.

@mdemetri - our posts crossed.

I don't think there is any problem with the 60s, 85s, etc. All the batteries could be 85 kWh, but software limited to the level of the battery that is swapped in. Pretty simple.

Doug - sure, pretty simple if you spend $6K for the extra cells you don't use. Lots of stuff is simple if money is no object. Cost matters here. In fact it's the biggest hill they are climbing.

Mdemetri - put a flashlight under the chassis tonight - no openings in the long panel that forms the bottom of the whole pack. Don't think the range pack cubby is there. TM staff always described that hump as holding more cells (for the 85).

Still looks like the frunk well is the likely spot. I think it will be larger than just the swuare well. We'll find out tomorrow.

Don't underestimate the "optionality" value of letting the driver stash more in the hatch, and being able to move them around at will without any machine, or to buy some at a store without the auto-loading fixture.

After I got I got up off the driveway, it sunk in that we haven't had this kind of fun since we hunted Easter bunny candy.

@DouglasR - yes the software can limit the swapped-in 85kwh battery but you would still have to store the battery that was removed, which will be both 60's and 85's. When you come back to get your battery, the robot will still have to know the difference so that you get back a 60 or 85. Still a logistical nightmare.

@Mark K - LOL; I would have looked under my car too but I am in Washington DC on buisiness. I think we will just have to wait and see the magic tonight. As I am in DC, please please post/blog from the event; I cannot wait for the video post at 12:30 am EST.

Yes, this is way too much fun. It is like Christmas eve when I was a kid. As this is the last annoucement for a while, I may go into Tesla annoucement withdrawl. Good thing I can find solace in driving the car!!!!

OK, @Mark and @mdemetri, you forced me to go back and look at that Reuters interview. The smoking gun is in the first five minutes, so check it out yourselves.

Throughout the interview, Elon refers to "the battery." Not "a battery," or "one of the batteries." He also said A Better Place (which swapped main batteries) got its idea from Tesla.

Then, at about 2:45 of the interview, I found this exchange:

Elon: In designing the Model S, I made sure we could do battery pack swaps -- rapid battery pack swaps -- and convenient, and also do high speed charging.

Reuters: Are we at a point now where it will be easy for people to do that, because the battery is pretty large, right?

Elon: It is, but it's in the floor pan, and it's capable of being removed and replaced very quickly.

If that doesn't persuade you, you're hopeless.

As to the "logistical nightmare" of keeping track of different size batteries, I suppose the simplest solution is to limit the service to 85 kWh batteries. But I don't think there is really a problem. Owners don't have to come back to the swap site and get the same battery, or even the same type battery. They will be given an 85 kWh battery that is software limited to the capacity of the battery they turned in. Is there some cost in having people carry around more battery than they have purchased? Sure, but some substantial portion of those owners will elect to have the software limit removed, and will pay serious money to do so, just as some substantial portion of the 40 kWh owners are expected to upgrade to the 60 kWh. And it will be a logistical benefit to TM to eventually have everyone on the same battery.

Guys, face it: the range pack idea is dead. If I were Mitt Romney, I'd bet you $10,000. It is a main battery pack swap. The only question is how TM will price it. And the most compelling way to price it is charge a nominal amount for the electricity, and use software limits to make sure the battery you get is the equivalent of the battery you turn in.

If you were swapping for a long trip and back, how about charging the 40/60 a little rental fee for the upgrade for the duration of the trip until the original pack is swapped back in? That way if you are happy with your 40/60 as a daily driver but just need that occasional extra mileage for the road trips, your covered!

Will the demo be live blogged? Is there a link yet?

Doug - thanks for the diligence, it's helpful for this hunt.

Elon's language certainly allows one to reasonably assume that its the main pack. To that standard, it points a main pack swap.

The contrarian view is that he talked about swapping to recharge, and he talked about the main pack being easy to replace quickly, but never talked about the two together. So there is some wiggle room for him to surprise, though admittedly its more of a stretch now. Especially with that last quote you cited, because of the form of Reuters question.

The reason I still cling to some hope they will go the extra mile is that it fixes a much bigger problem.

It's simply economically very hard to achieve location convenience by swapping the main pack. $50 million of capital only stocks 2,000 packs for the entire country. That's a very small number. To me, it doesn't suggest that it would truly meet the standard of "anywhere in the country".

A low cost range pack could fan out quickly to lots of locations, be affordable to stock at 10X the inventory. and would be a much more disruptive technology to boost adoption.

Perhaps that won't happen now, (it is hard to do), but there's an armada of patents by tesla aimed at exactly achieving that.

So maybe there's no technology mystery, and it's all about how they engineer the pricing, and that they qualify for swap ZEV credits. Or maybe we are going to be surprised.

But we'll certainly have some fun tonight!

I'm wondering why this is still debated since Elon tweeted unmistakably about this 2 days ago, talking about "pack swap demo".
The $50M-$100M investment quoted is most likely only for infrastructure alone, inventory (=batteries) is on top... demand will drive the expansion of this technology.

Mark, you're a bit like the Black Knight in Monty Python and the Holy Grail: you never give up! :)

Tobi - so you see the inventory being financed by the consumer. That would be on sort of a time share model - where you'd buy a 10% usage factor for say $3K. Is that sort of self-scaling your thought?

Doug - "Come back and fight like a man!"

The plot thickens:

Teh picture shows an ICE at a gas station ready to fill, but the MS has nothing around it, no main pack battery/no robot etc. The stop clock is set to 45s. So can they change the main pack in less then 45s and are just hiding the robot etc? IMO not a chance.

I am sticking with no main pack swapping and it will be a range pack into the 'floor pan' (as Elon called the casing for the battery on the bottom of the car).

Douglas R: On the face of it the qoutes you provide from Elon do not rule a range pack into the "floor pan". I may be delusional but.....

last sentence should be '...rule out..."

@Mark: actually not quite what I meant; the way Elon talked about the 50/100M investment in the Reuters interview, it sounded to me that he was solely refering to build the superchargers' swapping functionality.
At this point I rather wait for details from Elon during/after the demonstration about financial models. :)

OK, I'm going to go out on a limb here... It will be a full main pack replacement. But, it will be a 120 kWh battery and it will be available for all cars 40-85 kWh. Now here is the fun part... All existing batteries are already 120 kWh and simply software limited to either 60 or 85 (just like the 40 today). After your road trip, you get software limited back to your original kWh. You keep the new pack. As is it a 120 kWh, degradation over time isn't an issue. Or, just like the loaner car trade up option, you want to keep the 120, pay whatever the difference between your existing battery option and the 120 and bam, Bob's your uncle, you have a 120. I think the idea would be to remove the fear that the swapped battery you receive is used and or defective. But if it is defective, swap in a new one and your off again. Now the battery is just a commodity that you don't need or care to own anyway. Also removes the fear of batteries losing range over time. Just like you don't care about what gas goes in your ICE cause your just burning it anyways, you'll swap your battery without a thought. Or, Elon has perfected cold fusion and the new Mr. Fusion goes in the Frunk and charges your battery on the fly ;)

Mdemetri - that's true about the stage layout, but the counter is that the stage is elevated and it could be in the floor, or they could bring out a rig on wheels that does the deed.

On your floor pan notion, I think you can also get to the frunk from underneath. So a lot of possibilities.

Elon bright lined not getting out of your car, so that conjures images of driving up, something low profile happens under your car, and your drive off.

All of the mechanics of fast swap stuff is very doable when engineered right. That's never been in question.

My interest in the add-on architecture is the doubling of range, and the faster scaling of the network. Both of which are strategically very powerful.

But lots of recent statements do point to the less technologically aggressive path of just figuring out how to price the swap club.

We'll know soon.

Stark - that limb is a very skinny branch.

Probably a skinny branch over thin ice! Oh well, one can dream!

Hey guys... I just thought of something. I know, it happens a couple of times a year...

The Model S battery is basically a big rectangular 1,500 lb thing underneath the car. From what I saw at the Tesla store, the battery isn't all that thick - maybe 8" or so - but with lots of surface area underneath the car. What if every Model S already has a 2nd battery bay underneath where a 2nd 60 kWh or 85 kWh battery can be inserted for an instant doubling of range or the equivalent of a fast fill?

When I saw the chassis at Tesla, I couldn't help but think that there was potential to stack a 2nd battery.


That makes alot more sense then changing the main pack and would still qualify as a 'range pack'. The question is if there is clearance under the car for this?

I can see a 2nd Li ion add-on pack or a Al-Air add-on pack, no way main pack swap. I may also be on a very thin branch over thin ice, but what the heh!

@ampedrealtor...great idea, but that would add so much more curb weight. I'd be concerned about adding "anything" to the current car. changing the car weight dramatically will change driving dynamics as well as safety data that was initially presented with current weight. I don't think they'll do anything that'll change weight of the car "too" much. small change maybe, but adding on another battery pack, not likely.

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