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Comment by qntmfred | Hacker News Reader

I was hype until the part about it being total miles, not range on a single charge. And then I was disappointed. And then uninterested as I thought to myself "yeah that makes more sense." And then suddenly angry, as I thought to myself "wait why they hell AREN'T they trying to develop a million miles battery on a single charge!"

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You joke, but a while back there was a guy who had developed a new aluminum air battery technology.

"Jackson claims that if you replaced a Tesla Model S lithium-ion battery with one of his aluminum-air batteries of the same size, range would increase from 370 miles to 1,500 miles."

search for "jackson aluminum air battery"

There were articles where it was "a conspiracy" that he couldn't get funding for his breakthrough battery.

which leads to the downside: when the battery discharged, you had to recycle it and replace it with a new one.

Just to be clear, what Jackson is claiming to have developed is a new, better, electrolyte for aluminum air batteries. Aluminum air batteries themselves go back to the '60s. They have around 8 times the energy of a lithium ion battery of the same weight, or around 4 times the energy of a lithium ion battery of the same volume.

He seems to be doing better now on getting funding and interest [1].

I believe that the claims of 1500 miles in a Tesla Model S are based on the same volume. If you went for the same weight, you should be able to get an EV with something approaching 3000 miles.

That's enough that having to swap batteries when it gets low would be acceptable to many people, assuming it is reasonably quick. Jackson is claiming they could build swap stations that could do the job in 90 seconds, which if true is surely fast enough.

The discharged batteries can be recycled.

I believe I read somewhere that recycling the aluminum anodes from a discharged battery does take a lot of electricity, so you'd want to do that somewhere where electricity is cheap and green.

[1] https://www.automotivelogistics.media/electric-and-autonomou...

you have to admit - having to replace the battery, even only once a month, is a huge impediment to adoption.

Trying to develop a battery that can do a million miles on a single charge right now would be like telling a Chinese kingdom circa 500 AD to develop a working moon rocket because they have fireworks.

If you think about the energy required to drive a million miles, all concentrated and stored somehow in a car, it would be extremely dangerous. If that energy is suddenly released in an accident, it would probably destroy a city block.

1e6 miles at 3kwh per mile = 3e5kwh = 1.08e12 joules = 0.25 tons of TNT. Not sure how many buildings that would destroy, I have no practical experience with explosives. But it's a decent sized truck bomb.

I don't know, energy doesn't need to be that unstable, hidrogen fusion gives a lot of energy and don't need much mass of it, not more than current fossil fuel methods.

PS.: Of course no fusion reactor that fits in a car will probably de developed in the next years

Yep lets hope Telsa cars stay expensive and we get a public hyperloop instead and we can just ride bicycles around in the clean air.

Remember when Richard Hammond crashed the Rimic, it burned for 5 days!

At least we now know that a moon rocket is even chemically possible

I'm curious what the total energy storage would be, and what kind of destructive damage it could do. A million miles is a lot of miles to move a full Tesla, passengers, and luggage around.

Anyone want to do a back-of-the-envelope sketch and give some colorful units-of-measurement given instantaneous discharge (e.g. tons of TNT)?

Assuming 500 watt hours per mile for Cybertruck (likely the first Tesla vehicle using it), a million miles is 1.8e19 ergs.

1 kiloton TNT is 4.184e19 ergs.

Million mile battery is 0.43 kilotons TNT, about 1/35th of a Davey Crockett man-portable nuke.

Well, a more reasonable value for a tesla is 300 wh/mi, and a tesla could pull off 1,000,000 miles of range with a mere 12.91 gm of plutonium.

If the the cybertruck really needed 500 wh/mi, it would require a bigger million-mile battery - say 21.53 gm of plutonium.

But you know the environmental folks would complain bitterly, so maybe tesla should offer a "green" cybertruck option with a heavier 22.66 gm thorium battery. It will probably require retuning the suspension for the extra weight.

https://en.wikipedia.org/wiki/Energy_capacity

Just have to efficiently & compactly convert thorium to electricity at a suitable rate in a sub-1000 lb package priced under $65,000 (cost of battery + 500,000 kWh).

I picked 500Wh/mi because Cybertruck will likely be first to use the new batteries, and will require more power than the cars/SUVs.

Based on this[0] thread on the Tesla forum, I'll use 0.31 KWHr/mile. If that's the case, a million mile battery would be equivalent to 267 tons of TNT.

[0] https://forums.tesla.com/forum/forums/miles-kwh [1] https://www.wolframalpha.com/input/?i=%280.31+KWHr%2Fmile*1+...

Dividing 1000000 miles by the up-to 390 mile range of the 100 kWh Model S indicates 256.4 megawatt hours for a million miles. That's about 221 tons of TNT equivalent.

Well using the most optimistic numbers I could find the Model 3 LR does ~429km on 270 MJ battery pack. Assuming efficiency of system remains the same for 1 million miles that is approximately 1x10^12J of energy, roughly 240T of TNT or around 30,000L of Jet A-1.

Using your figure of 1e12 joules, I thought, what about a hypothetical miniaturized fast breeder nuclear reactor?

Googling, I found a document that says regular light water reactors produce power with something like 1.8 tons of fuel per gigawatt per year. And fast breeder reactors potentially could be 100 times more efficient, they say.

So if I did the arithmetic right, and if Google unit conversions didn't fail me, you could get 3.2e16 joules from 1632 kg of uranium fuel, which ends up being about 2 ounces per 1e12 joules.

So, sure, it seems doable to me. The "battery" would be about the same weight as a regular alkaline 9V. A bit smaller though.

Lol so apparently this sounded like a good enough math problem to get a lot of people interested

Ok so.. 100kwh = 350 miles ish

1,000,000 miles would need a capacity of 285mwh...

Or... 245 tons of TNT...

I don't want to be in the same zip code as that vehicle

Works as long as you can stop by a suitably naive civilization every so often to strip-mine dilithium crystals for a few bottles of synthahol.

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