I understand the desire not to raise expectations to unrealistic levels. That said, if Elon's tweet is to be taken at face value, it does seem on the order of a range extender battery or battery swaps.
"There is a way for the Tesla Model S to be recharged throughout the country faster than you could fill a gas tank."
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Excellent point Raymond. Aluminum replacement via self-help vending machines doesn't seem feasible. I don't see this as ruling out the possibility of metal air battery range extender.
It could be an option they offer for $X to install a 1,000 mile extender into the car. 98% of the time it's just a backup, that if for some random reason in daily driving you are running out of range, you dip into your 1,000 mile extender. I'd imagine typically this aspect of use (tapping 10 miles in January, than maybe in May another 30 miles...) would take years before you'd finish of enough of the 1,000 mile cushion to need to drive to a service center and have the aluminum replaced.
The other 2% of time would be when you are going on a very long drive, for example 1,500 miles. The extender would give you much greater flexibility for your trip. If you think about an actual scenario I think it would be a great complement to the SCs. Picture you're driving along, and after 3 hours, you really don't want to pullover and Supercharge, but the next Supercharger is 150 miles away. Very well, keep driving another 2 hours on your metal air extender, using up 150 miles of it's 1,000 mile capacity. 5 hours into your trip, you likely want to stop for an hour... perfect time to Supercharge. Oh, a 5 cars waiting for 2 Superchargers? No problem, add water for extender, drive 2.5 hours to next Supercharger and charger main battery there...
Perhaps on such a 1,500 mile trip you might dip into your extender 500 miles, and same on the way back. At your convenience after your return home from your trip, you drive to a service center, and they replace this 150 pound battery for you, and you're probably set for at least a year (I think the overwhelming majority of people drive 1,500 miles once a year or less, if at all.
People would feel a huge backstop of battery power, and probably become aware over time they don't hardly ever need the extender. Rather than needing to be convinced range anxiety is overstated, people could learn this with the extender as a sort of set of training wheels (and ten years from now main battery will probably have range making an extender obsolete.)
"There is a way for the Tesla Model S to be recharged throughout the country faster than you could fill a gas tank."
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Wikipedia says practical density for Aluminum-air is 1300 Wh/kg so "recharging" 60 kWh means removing 45 kg (100 lbs) and installing 45 kg. Lifting more than 5 kg is impractical so that's removing and inserting = lifting 5 kg (11 lbs) 18 times.
Assuming 45 kg Aluminum, you also need 53 kg (53 ltr; 15 gallons) of water.
Multiply all by 1.4 for a 85 kWh charge.
So while you're all sweaty from removing and installing 45 kg metal just as you begin to pump water the ICE in the background drives off with a full gas tank.
Not a good demo.
(I'm no chemist - I think these numbers are correct, however)
Excellent point Raymond. Aluminum replacement via self-help vending machines doesn't seem feasible. I don't see this as ruling out the possibility of metal air battery range extender.
It could be an option they offer for $X to install a 1,000 mile extender into the car. 98% of the time it's just a backup, that if for some random reason in daily driving you are running out of range, you dip into your 1,000 mile extender. I'd imagine typically this aspect of use (tapping 10 miles in January, than maybe in May another 30 miles...) would take years before you'd finish of enough of the 1,000 mile cushion to need to drive to a service center and have the aluminum replaced.
The other 2% of time would be when you are going on a very long drive, for example 1,500 miles. The extender would give you much greater flexibility for your trip. If you think about an actual scenario I think it would be a great complement to the SCs. Picture you're driving along, and after 3 hours, you really don't want to pullover and Supercharge, but the next Supercharger is 150 miles away. Very well, keep driving another 2 hours on your metal air extender, using up 150 miles of it's 1,000 mile capacity. 5 hours into your trip, you likely want to stop for an hour... perfect time to Supercharge. Oh, a 5 cars waiting for 2 Superchargers? No problem, add water for extender, drive 2.5 hours to next Supercharger and charger main battery there...
Perhaps on such a 1,500 mile trip you might dip into your extender 500 miles, and same on the way back. At your convenience after your return home from your trip, you drive to a service center, and they replace this 150 pound battery for you, and you're probably set for at least a year (I think the overwhelming majority of people drive 1,500 miles once a year or less, if at all.
People would feel a huge backstop of battery power, and probably become aware over time they don't hardly ever need the extender. Rather than needing to be convinced range anxiety is overstated, people could learn this with the extender as a sort of set of training wheels (and ten years from now main battery will probably have range making an extender obsolete.)