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Comment Re:I say BS (Score 2) 114


And I'm telling you that lithium-ion batteries are not a "single tech", that they've dramatically improved in power and energy density (both volumetric and gravimetric) over time. And if you doubt this, I repeat: go find and older lithium-ion battery and compare it to a new one.

As for li-air, yes, the maximum energy density of li-air is about 10x of the maximum of li-ion. Namely because it works by direct oxidation rather than intercalation, so you don't need the mass of the matrix into which the ions get intercalated. It is not a "magical tech". It exists. Like all technologies in all fields, however, you have to reach production specs. This means not only maintaining a combination of safety, reliability, longevity, efficiency, temperature range, power density (charge and discharge) and energy density, but also affordability in mass production. And to be able to guarantee that you can do all of these things to a high enough level for investors to take the risk.

As with all technologies, you start out with promise in one or two fields, but serious problems in many others that you have to deal with. With time you refine them, until all of refined to a state where the product is commercialized. Li-air has actually been advancing quite well. In the early days one of its biggest problems were efficiency and longevity, but they've made huge strides in both in recent years. Lithium sulfur still looks nearer term, but commercialization of Li-air appears to have gone from "possible" to "quite probable".

Comment Re:Halfway There (Score 2) 373

Right. Out of the 330 million people in the US (not counting the broader market, there's "nobody" who wants a gun that can't be accidentally picked up and used by their young children or an intruder. Literally "nobody". Yeah, totally believe you.

They have a niche. You want to prevent them from filling it.

Comment Re:Progress! (Score 4, Interesting) 114

Actually, that is a concern. Li-ion batteries don't have lithium metal in them unless something goes wrong. Lithium-air batteries always have lithium metal in them, by design.

In practice, you'll probably see a bit of the energy density given up in order to beef up the casing to prevent rupture/fire.

Thankfully, lithium-sulfur batteries don't use lithium metal, just lithium polysulfides. The max energy density isn't as high, but it's still quite good. They're already on the market, albeit in small quantities for applications that require the absolute highest rechargeable energy density (mainly aerospace).

Comment Re:I say BS (Score 2) 114

Yes, cue the standard "Batteries haven't advanced!" stuff from people carrying around cell phones with significantly more amp hours in a smaller battery profile than the last generation phones that they owned.

News flash: every time a new tech advance makes it into a product, they don't mail a letter about it to everybody who read an article about it years earlier. Example: hey, remember all of that stuff about breakthroughs in silicon anodes several years back? Yeah, they're in batteries now. Even Tesla is starting to use it in their higher-end packs.


Researchers Predict Next-Gen Batteries Will Last 10 Times Longer ( 114

Lithium-metal electrodes could increase the storage capacity of batteries 10-fold, predict researchers at the University of Michigan, allowing electric cars to drive from New York to Denver without recharging. Using a $100 piece of technology, the team is now peeking inside charging batteries to study the formation of "dendrites," which consume liquid electrolytes and reduce capacity. Slashdot reader Eloking quotes New Atlas: Battery cells are normally tested through cycles of charge and discharge, testing the capacity and flow potential of the cells before being dissected. Dasgupta and his team...added a window to a lithium cell so that they could film the dendrites forming and deforming during charge and discharge cycles.
In a video interview they're reporting that dendrites can actually help a battery if they form a small, even "carpet" inside of the battery which "can keep more lithium in play." According to the article, "The future of lithium-ion batteries is limited, says University of Michigan researcher Neil Dasgupta, because the chemistry cannot be pushed much further than it already has. Next-generation lithium cells will likely use lithium air and lithium sulfur chemistries."

Comment Re:67% is not that good (Score 2) 119

It's good for the NAO. When you're pushing the boundaries, anything over 50% is good.

For long-term climate models, things like the NAO average out across many years. For short-term weather forecasting, you have a week or more before the system diverges enough to cease to be useful. But it's tougher working on those in-between scales.

Comment Re:No it can't (Score 1) 119

Should be well worth it in terms of things like planning for agricultural products, natural gas supplies, etc.

The real issue however is that they've validated it with hindcasting. Which is certainly something, but isn't as ideal as you'd want. It's trivially easy to fit any arbitrary past dataset to a statistical model if you have enough parameters that can be tweaked, but that doesn't mean that you're actually capturing the underlying dynamics. That said, from the sound of it it's built around a physical model, so that increases the odds that it actually is, rather than just fitting to some arbitrary curve.

Comment where will it end? (Score 1) 74

I won't dream of a single (or multiple) damn quantum thing until I see an equation that describes a real-world superposition scaling limit, species type "immovable object".

I believed in Moore's law because it was on a collision course with the atom, right from day one. Even as a child, I didn't believe in a Laplacian universe, in the sense that the accumulated knowledge required to compute the deterministic outcome could exist in one place—a place smaller than the universe itself—for any value of "smaller" my small mind was capable of entertaining.

I've been reading articles about quantum computing seemingly for decades now, and not a single article has pointed out any practical scaling limit. For all these dunderheads seem to know, we could cajole the entire universe into a state of Laplacian superposition, if only we didn't suck at stacking these tiny little Lego blocks.

No scaling boundary equation widely promulgated = no credibility widely disseminated = very little fantasy action for people who don't believe in giant green men with anger management issues.

Comment Heh, haven't heard that name in a while. (Score 1, Interesting) 168

I used to follow some of what The Jester wrote. There are a number of people out there who think he's overrated, more brag than anything else. Still, I saw some pretty clever things out of him. For example, at one point he was going after some other hacking collective (I don't recall which one), and he announced a successful attack against them and posted a list of all of their names and real IP addresses. Only, the list wasn't real. Instead, anyone who tried to download the list had their connection logged and probed, an exploit used to trigger the computer to make a (real) TCP connection back to one of his computers, and a number of automated attacks launched against targets it considered particularly suspect (for example, if there was evidence of being logged into a known member twitter account). I.e., it wasn't actually a list of suspects, it was bait to build a list of suspects. I think he did the same trick with QR codes later.

Comment Re:Halfway There (Score 2) 373

Apparently I missed the part of this story where these manufacturers are trying to take your guns.

And on that subject, how many people have you guys turned out to the polls every time warning that the Democrats were with some imminent plan to take all your guns the second they take office? How did that turn out? Apparently I missed the massive seizure of privately owned weapons that you guys are constantly talking about.

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