Charge faster than you could fill a gas tank?

Charge faster than you could fill a gas tank?

Latest Tweet by Elon Musk. What does he mean?

"There is a way for the Tesla Model S to be recharged throughout the country faster than you could fill a gas tank."

Brian H | May 27, 2013

I note the video says charging a car would take minutes, not a "couple of seconds". That's 2 orders of magnitude difference; anyhow, the Model S already charges 50% (a normal usage refill, at a supercharger) in about 30 minutes or so; cutting it down to 15 minutes (or less) is not a big stretch, even with available tech.

It may revolutionize cell phone and laptop storage in short order; cars will take rather more engineering.

rchiang | May 27, 2013

If one AA battery can charge in 5 sec maybe 100's can charge couple of minutes. Within 10 years when I change my battery on my MS they will definitely have the technology by then. I first heard about this technology before beginning of the year that's why I knew that battery car will be the way of the future.
What I hear they probably going to team up with china to produce this battery and they probably already have this battery but its not in production because they are working on the patent stuff and paper work. In the labs they already proven its already works good.

dstiavnicky | May 27, 2013

I think I've figured it out... drive around in a thunderstorm with a kite flying from your Pano roof and the Tesla key dangling from the kitestring...

lph | May 27, 2013

I am wondering if Tesla has figured out a way the anode is swappable like a toner change in a printer? That could mean that the unit could be "recharged" by almost anyone and take only a couple of minutes. Could also carry some extra anodes along with you for extra milage. This way the battery package would not have to be heaved in an out of the frunk at every "recharge" but just a book sized object. Just guessing here.
However looking at some of the patents Tesla has it appears that they have figured a way to electrically recharge a metal - air battery (did not know that this could be done) with the help of using some kind of oxygen and electrical management system.

Mark K | May 27, 2013

lph - exchangeable anodes are very cool, but I think there's still a liquid electrolyte that needs refreshing. If so, that might be too messy for the average consumer to do them self, but certainly viable at a swap center. That would greatly simplify the recycling logistics.

jbunn | May 27, 2013

Somehow driving around with a frunkfull of electrolyte that turns aluminum into aluminum oxide seems like a bad idea in an aluminum car.

Did a bit of battery research overnight. Yes, aluminum air has great power density, but the release of power is destructive to the aluminum in the battery. it either turns into a gel, or a powdery sediment at the bottom of the battery. That needs to be removed, the electrolyte replaced, and the aluminum replaced. Turning the aluminum oxide back into aluminum metal is only about 20% efficient. Not a heck of a lot better than car efficiency.

You could do it, but what's the cost of building the batteries, running the exchange centers, and providing the processing. These batteries are in use by the military, but they are somewhat free from cost restraints and environmental regulations.

I can't imagine a company who's goal is to get gas cars off the road wants to set up infrastructure of messy chemical processing with aluminum oxide sludge, potassium hydroxide, and other light and heavy metal reprocessing.

lph | May 27, 2013

Tesla patents talk about metal air batteries which could be lithium or other metals, so reacting with the car frame is not a given.

Mark K | May 27, 2013

Jbunn - I think the idea is this -

It's an enabling element in the product mix that gives the car range that is unprecedented even by gas standards. It also trumps gas on refill time.

That completely reverses conventional wisdom on EVs.

Viewed from the % of operation where you'd actually use this option, the efficiency compromise is immaterial.

PorfirioR | May 27, 2013

The process does not need to be as messy or dangerous as it sounds. Also, the projected costs are around $1 per Kg based on recycling the batteries. Granted, that it might take a small breaktrhough to make the whole thing viable, but I am hoping that's the mystery announcement.

Logistics-wise, this could be no different than the way you buy propane tanks for your grill. The whole battery could be made into a sealed pack about the size of a small cooler, with its own insulation, management, and protection mechanisms built in.

If the projected costs of Al-air battery technology hold up (~$1/Kg), a 25Kg pack could be offered for rent at around $35 (accounting for profit/overhead). However, at the current state of Al-air design projected density, that size pack would only provide ~37.5kWh which does not yet provide a competitive cost/range to gasoline. That's where we need a minor breakthrough.

As we have already seen time and again, Tesla does not only look for technological breakthroughs. This could come in the form of financial incentives, making the recycling process cheaper, cheaper materials, etc. In other words, we are almost down to only needing a cost breakthrough - $20 per 100 mile range would be a good target, knowing that it will get cheaper from there.

The more I think about it, the more this strategy makes sense, even if this is not the big announcement.

bb0tin | May 27, 2013

Even if the battery could not be lifted by one person it would be cheap and easy enough to have a dolly do the job. Because the batteries are safe and can be stored a long time, an electric refill will be available in places where petrol is not available. eg: remote tourist destinations and small towns. The battery would solve the range anxiety issue once and for all. If this is what Tesla has done, then the ICE manuafacturers will finally see the writing on the wall because it will be lit up with a floodlight.

PorfirioR | May 27, 2013

@lph - thanks for pointing out the patents.

I found an article that sums things up pretty well. I don't know how I missed this before:

Definitely adds more weight to the argument for dual battery with swappable pack.

Follow this url to see Tesla Motors' patents:

I will have to take that patents list with a grain of salt and temper my expectations, since I see a few patents for what appears to be range-extended vehicles using ICE (say it ain't so Tesla). Hopefully those are red-herrings or some maneuver to qualify for credits, etc. Let me quote the offending language here to save you some reading: "...said engine burning fuel selected from the group consisting of fossil fuels, synthetic fuels and bio-fuels..."

Now I am really hoping for swappable battery packs.

therealmach3 | May 27, 2013

My initial thinking on battery swapping was something like "huh?! why on earth would I want to have a bot screw (pun intended) with the structure of my car?" However, I have become a believer. I was literally on all fours inspecting the model chassis (the standard one they display at the galleries) at the Santa Monica store a couple of weeks ago. The sales guy assured me that the car had been engineered to enable the battery to be changed "in less than 60 seconds". Aside from what the sales guy may or may not know and whether he has his facts right ... the battery really seems to be attached specifically to enable quick swapping.

hsadler | May 27, 2013

No, the battery is attached for 'easy' swapping not necessarily quick.

I have heard times of 30, 20 and now 1 minute. All from 'experts' who probably two years ago never heard of Tesla till they got the job there.

May be quick once you got it up on a lift and stabilized for sudden change of weight distribution.

I believe the 'under your nose' announcement will surprise many people. Although, this has been entertaining.

Mark K | May 27, 2013

Swapping the main pack reasonably fast was designed in from the beginning.

Haven't read the law, but I wouldn't guess the 7 to 4 ZEV credit boost is not contingent on whether its 30 seconds or 30 minutes. So swapping one way or another is a must-do to get those credits.

The issue is not so much if swapping the main pack can be done, but rather whether it produces the greatest benefit.

- The extra pack could double range, swapping the main one doesn't.

- The extra pack is much higher energy density than the main pack.

- The recyclable extra pack in Al-Air would have far lower capital cost, since it's a much less complex subsystem than a carefully managed rechargeable lithium ion main pack. That makes the swap infrastructure inventory far cheaper.

- Managing care of expensive capital assets (main packs) that get passed around is not fun.

So if it's doable, the extra range pack is a much bigger win.

The only argument against the frunk pack as the swap medium is whether or not TM can techincally pull it off right now. If they can't, they should still at least offer to swap the main one to get those credits.

But I very much hope they are able to go all the way with this.

It'd be a quantum leap that totally rewrites the rules of the auto industry.

therealmach3 | May 27, 2013

fair point ... heck if I know

TI Sailor | May 27, 2013

Does NHTSA or another agency have to review/test/approve changes in the frunk area to accommodate the swappable packs? It seems to me there may be safety issues with the addition of 100+ lbs. Perhaps Tesla has already addressed this with NHTSA, but suspect someone would have picked up on that by now.

Mark K | May 27, 2013

The issue would not be the cargo weight, but an energy release.

The Al-Air batteries are passively safer, since they are less prone to melt-down. (They have higher internal resistance). I'm sure TM would enhance safety further with clever electrode structure and packaging.

That all takes work, and at this point we don't know if they've done it. But it's possible. And what's at stake makes it worth such an effort.

As to risk, don't forget that there is no NHTSA reg preventing you from carrying filled-up propane tanks in your frunk. (Personally I'd put them in the back).

amirm | May 27, 2013

I think the issue of extra credits is a red herring. Elon said it would not be a factor beyond this year and I read that he could only sell it to other manufacturers until they produce enough green credits themselves. All domestic guys are expected to have enough credits by later this year so that Tesla can't monetize its credits....

Mark K | May 27, 2013

amirm - I believe you just made the case for TM to move quickly before the ZEVs disappear.

up north | May 27, 2013

how would the weight of a battery pack over the front wheels effect the handeling of the car, and how much is this pack going to weigh?

Robert22 | May 27, 2013

Easy enough to find out. Roll a couple of free weights from your universal gym into the sub-frunk and take it for a spin :)

mdemetri | May 27, 2013

I think there is another very important advantage of a swappable secondary Al-Air battery that has not been considered: not only would an Al-Air secondary battery extend range, but it also would address the issue of battery life and the risk of having to replace an expensive battery pack in 8-10 years. If the Al-Air is used frequently, this would directly extend the life of the main pack by reducing the number of charges. If the Al-Air battery is not used frequently (or not at all), then even with a 50% or more decline in capacity of the primary Li pack, the individual could start using the Al-Air and essentially greatly extend the life of the car. A 20 or more year lifespan of the car could easily be achieved. Better than ICE again!!!!!!!!!!!

Thus, a secondary Al-Air battery solves the two major problems for widespread adoption: range and life-span of the battery!!!!!

I first proposed a secondary swappable graphene supercap for the frunk (comment above), and then changed this to a secondary Al-Air (in another thread) given others comments. With continued discussion and comments by others, it is clear that this approach is a slam dunk and will kill the ICE if done.

I am now so convinced of this approach, if Tesla does not do it I may just have to do my own start-up and do this (Ha Ha Ha).

Mark K | May 27, 2013

Mdemetri - I think Seal Team 6 is already on it.

All of those patent filings did not self-assemble. Serious intellectual energy has been put toward this.

mdemetri | May 27, 2013

Mark K

I sure hope so, I want Tesla to do this badly

However, it is important to note that patents have limited power; all they do is give one the right to sue. Just look at the Samsung - Apple squabbles for an example. If Tesla does not move forward with this approach, their patents will not and should not halt this approach.

But I am with you, I think Tesla is all over this and will do it. I can't wait; I want this to happen ASAP.

jbunn | May 27, 2013


The $1 per kilogram price as I recall is for the aluminum plates in the battery. It is NOT the cost of refurbishing the battery after use. The battery needs to be flushed of spent aluminum and electrolyte. Potassium or Sodium Hydroxide are caustic (I have had a bad chemical burn from working with it in the lab). The chemicals need to be separated and reclaimed.

Everyone seems to be in the wild enthusiasm phase about this, and few folks are considering the cost.

What's the cost of building a pack? Having enough on the shelf so when drivers arrive there is one ready? (pack float might be 7 to 1. 7 packs for every 1 in use). Now building manned or automated service centers on all routes. How much does that cost? Aluminum batters do better in storage dry where the electrolyte is added at time of use. How does that get done and what does it cost to staff that? How are used packs taken to be recycled? Does tesla need to create regional aluminum reprocessing centers?

People talk about energy density, but has anyone run the numbers on this? Better Place just went bankrupt with a MUCH simpler process in a much smaller geographical area. You expect Tesla to do that?

Finally, if the pack fits in the frunk, it needs to fit snugly. It can't move around at all for safety and ride stability. Will it fit the Model X? Some of those will have front wheel drive and may sacrifice frunk space. It probably won't fit in the smaller Gen III or new Roadster. What gets built MUST be a long term solution for decades of new Tesla models.

Hate to rain on the parade but it's not going to roll out with today's technology. Not.

I hate to rain on the par

mdemetri | May 27, 2013

Hmmm, I think similar negative arguements on feasability/cost were made about Tesla sucessfully bringing a long range EV to the market. Many 'shorts' betted against Tesla and have payed dearly for this.

While I agree there are obstacles, and cost is the largest one, as I said in an earlier post, if anyone can do it, Elon can. Elon has shown an exceptional ability to take existing tehcnology and bring down cost to make it viable. No reason why he could not do this again; and if not I am convinced that someone else will. The concept is just that good.

jbunn | May 27, 2013

I agree that we all got a good laugh at John Peterson's expense. I've been a Tesla fan for over 4 years now, and have owned my Tesla for 4 months.

However... Because there were foolish arguments about electric vehicles that Tesla proved very wrong does not mean that Tesla can bend the laws of physics and economics.

Again, I'd say run the numbers on the issues I present, the vast geography required, and consider the space requirements in the car as they relate to forward compatibility.

I have a great deal of respect for Tesla and am heavily invested. I believe they are not foolish enough to go down this road.

Mark K | May 27, 2013

Jbunn - Well, if you think it's too much of a stretch for this team, do you think it more likely they will swap the main pack? How's that going to work from a capital equipment cost perspective?

Remember they have officially declared they'll have swap facilities soon, so something's going to happen. I don't see them waving off tens of millions in near term ZEV credits.

Not simple to introduce new packs, for sure. The devil's always in the details, but I think they've got a shot at getting something going next year. It may have iteration one limitations, but that's how anything gets started.

We don't know what they've already achieved quietly, and their patents don't suggest they've been idle.

They look for significant advances that are exciting changes for customers. This would qualify.

To bet against it, is to bet for swapping the main pack. Maybe that's all they can do, but that doesn't seem as exciting.

I think they've got a chance to really break loose here. We'll know some weeks from now.

ewilmann | May 28, 2013

First of all, a battery swap does not constitute a "recharge", as Elon puts it. Also, the notion of swapping cars is lunatic, just think about it. A family roadtrip with a stopover to repack your stuff into a used car? Will Tesla have personell scattered around major roads to keep the cars clean and fully charged? I will sop here. Though I really enjoy reading these highly speculative forum threads, I can't wait to get the long awaited answer. Elon is a marketing genius, I'll give him that. :-)

liviu | May 29, 2013

In Europe, Renault introduce the swap concept from the begining. The EV line of cars will can swap the battery and this is presented before the first production car is made. That is not a big deal.
For example, Renault sell you the electric car and you pay for 3 years a month rent to lease the battery and after 3 years the battery is not yours, just you use it and has warranty for a long period. The battery is never yours because after lifetime expire is still precious for recycling.

machmike | May 29, 2013

NatGeo "MegaFactories" episode on Tesla.
4:25 second battery installation.

Just saying...

mdemetri | May 29, 2013


Please clarify; I looked at 4:25 of the video and did not see/hear anything about a second battery installation. Is it somewhere else in the video?

Brian H | May 29, 2013

you misunderstand; he's saying somewhere in the vid a 4.25 installation is mentioned. IIRC, the battery is mentioned somewhere after the 40:00 mark.

Brian H | May 29, 2013

41:40 No mention of time for the battery; 4 min 40 sec for the drive train.

HenryT2 | May 29, 2013

A guy named Randy Carlson wrote about finding out that Tesla had upped their order for frunk liners to 650 a week, which was more than Tesla was producing in cars/week. It led him to conclude a second motor would be added to the front of the car. I guess it is possible, but I think the second battery is far more likely. Far less complicated and far more valuable to Model S owners.

herkimer | May 29, 2013

If you look into the frunk and notice the location of the box at the back, it is directly over the front axle and it's protected by the entire crumple zone structure of the front end. The location actually completes the weight balance distribution of the car to near 50/50. Therefore handling wil not be adversely affected, likely even to be somewhat improved. Also take a look at the back of this odd square structure and you will notice that it is already outfitted with what appears to be a slot for connection. If a swappable battery pack of this size had already been designed into the car, and will extend the range to 500 miles or more, this will effectively end any argument for ICE. All evidence suggests that this was built in to the Model S and Elon's plan. Look out, cause the last announcement of the 5 part "trilogy" will be a major milestone in the electric car revolution that Elon has envisioned. Seismic shift is about to take place.

DouglasR | May 29, 2013

Are these batteries commercially available? Has anyone seen them in operation outside of an experimental prototype? Do you think it likely that TM would place a battery in a production vehicle if that battery had not been thoroughly tested and used, as lithium ion batteries have been.

Mark K | May 29, 2013

DouglasR - Given Tesla's patent filings, the battery may well be a custom design of TM. That would give them the optimum control to match it to their needs for recharging the main pack, and cost-effective recycling.

The provisions in that back plate in the frunk-well are consistent with the hypotheses of the add-on quick-swap pack.

This development is more important than most folks understand right now.

Lush1 | May 29, 2013

Car swap seems far fetched and undesirable, I would think, to most folks, for many reasons. For instance, what if you unpacked all your luggage, tools, electronic devices, kids, diaper pail, tissues, glasses, and driving slippers from your beautiful red, white, blue, black, green, or brown Model S and they expected you to pack it all into a brown, green, black, blue, white, or red one to get you the rest of the way to grandma's house? Would you want to be seen in a Tesla in THAT color? Ugh! And are you going to leave behind the cool lighting mods you did to the frunk and footwells and the Masonite center console you built? And what about the sanitary issues? What's that smell? Did the last family that had this car wash their hands after hitting the rest stop? Was a dog scooting its rear end around the car's rear end? How clean is clean enough? OK, if you can get past all those hurdles, wouldn't you LOVE to turn off the traction control on a Tesla, see how much rubber it can burn, see how fast it really goes, measure how high the curbs it can clear at each suspension setting and practice power slides through the apex of freeway off ramps? Would you do these things in YOUR Tesla? (Sadly, I fear they've all been done). I wouldn't do any of these things to mine and I bet most of you wouldn't do them to yours, but a loaner? Even Tesla owners sin, albeit occasionally. I'm just getting started, but I'll stop before my wall of text becomes its own page. Any nays?

SamO | May 29, 2013


Carswap is awful. But I could see Tesla having a fleet of service loaners that could serve dual purpose from time to time.

SamO | May 29, 2013

A more detailed map will go out tomorrow, Musk says. “You’ll be able to drive all the way from LA to New York using the Supercharger network,” he says. I believe the target for that announcement was by next year.

SD Supercharger | May 29, 2013

“I guess I might as well let the cat out of the bag,” Musk says to cheers. He starts talking about the SuperChargers, Tesla’s recharging infrastructure for making it possible to take a Tesla on road trip. “We had to make something that was really quick to charge. What we were going to announce tomorrow is that there is going to be a dramatic expansion of the Supercharger network. By next month we’ll triple the coverage area.”