Join The Community

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."

I think @james babb's comments above finally convinced me.

Although I think battery swapping is a bad idea, and many here seem to agree with me, I could not let go of the fact that Tesla itself had mention it in some of their SEC filings (

Then, there were the cryptic messages regarding "right under your nose" and the ability to refuel as fast or faster than an ICE vehicle.

So james has nailed it, in my opinion.

Therefore, I now think that we might indeed see battery swapping, but only for a secondary range-extending metal-air battery. I believe that, if we could see a battery of at least 60kWh in a 25Kg or so swappable pack that can be rented for cheaper than the equivalent range in gasoline, that would make ICE vehicles pretty close to obsolete overnight.

PorforioR -

That's the beauty of it - it's a sudden turning of the tables.

You go from:

EVs have shorter range and take longer to fill than average gas cars,


EV's go farther and fill quicker than the very best gas vehicles.

It upends everything. Once this is in place, the Model S will roundly beat all gas cars on every single performance metric.

That's a big deal.

Ask Panasonic? Anyway, something not magical but very interesting must be in the works.

With aluminum air batteries reaching around 1.5kWh/kg you could easily put an additional 100kWh (adding 300 more miles) yourself into the frunk of your Model S by just lifting 4 batteries weighing 15 kg each.
There is no need for having a complicating robot exchange station!

My guess would be graphene battery! This will be the battery of the future.

This will charge a car in couple seconds probably faster then gas can pour into the gas tank.

@rchiang fascinating! I will definitely have to research that tech further.

And how would you hook them up? Good luck with that, but I doubt it.

At how many MW? A cable as thick as your leg would be needed, and/or voltage and amperage that would fry you in a millisecond if it shorted.

Bad idea.

@Brian H
I did a little research awhile back because I had the same impression. Assuming you had two large graphene supercapacitors, how would you transfer energy efficently between then? Graphene has some nice properties where electricity is concerned. It is more conductive than any metal and can carry 1-2 orders of magnitude the current that copper can.

In much the same way fiber optics replaced copper for high throughput communications, graphene will replace copper for electrical power transmission. We won't get there over night though.

In theory, graphene will be a transformative material for electricity storage, transmission and a lot of other needs. But deploying it will take some time because there are a lot of practical issues to address.

Some years from now, we will see exciting advances because of it. But it is a ways off.

What is before us in the near term is Al-Air batteries that are in use today, and are an order of magnitude higher energy density than the rechargeable LiIon pack.

I'm hoping we see this as a quick swap range extender pack for the Model S soon.

Ok, so the weight of the cable may decrease somewhat. But the voltage and amperage won't. Not "Self-serve" stuff. Do you have ANY idea what a megawatt can do? Much less 10-100 MW, which is what you are talking about when you say "charge in seconds"? Reality bites.

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.

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.

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...

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.

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.

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.

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

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.

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.

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.

@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.

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.

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.

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.

fair point ... heck if I know

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.

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).

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....

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

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?

X Deutschland Site Besuchen