23 January 2017

The Asymptote of Progress - part the first

A continuing theme here has been exemplified by Gordon's book, which thesis was obvious to your humble servant long before the book was published. I expect, given this missive's title, more such.

On various forums, I've been the Debby Downer when the discussion turns to predicting future tech. Since much of such tech is mobile and semiconductor driven. And that means, perforce, battery driven. More function demands more power. Give me Power!!! And I've had the temerity to point out that battery power density hasn't moved much, certainly not on the order of magnitude scale, in a very long time. The counter argument has been, 'well, as nodes get smaller, they get more power efficient, so stable power availability doesn't make so much difference'. But we know that as nodes get smaller leakage and capacitance control go from nuisance to significant.
There are other issues. "The primary challenges will be contact resistance reduction and channel mobility improvement for better performance," Lam's Pan said. "We also need innovations to reduce parasitic capacitance."

Even if smaller nodes can be made, why would you?
In fact, it costs $271 million to design a 7nm system-on-a-chip, which is about nine times the cost to design a 28nm device, according to Gartner. "Not that many people can afford to (design chips at 10nm and 7nm) unless they have a high-volume runner and can see a return-on-investment," said Samuel Wang, an analyst with Gartner.
Ah, that old average cost, "we lose money on each widget, but make it up with volume" meme.

It is the middle ground between light and shadow, between science and superstition, and it lies between the pit of man's fears and the summit of his knowledge. ... It is an area which we call the Asymptote Zone.
[sorry about that, Rod]

Which brings us to today's autopsy of Samsung's burning batteries. In an effort to provide the oomph needed to drive function, they slid through the asymptote and over the cliff.
For batteries from both companies, the use of high-energy density cells increased the risk for thermal runaway during a short circuit, especially when the battery was in a high state of charge.

The NYT, on the other hand, notes (hehe) that design issues existed as well.
But battery scientists, including those who spoke at the announcement, said aggressive decisions in designing the batteries made problems more likely. Pushing to make the battery thinner and more powerful, Samsung opted for an exceptionally thin separator in its battery. As the critical component that separates the positive and negative electrodes in a battery, separators can cause fires if they break down or contain flaws.

While the tale is primarily one of manufacturing FUBAR, this was all driven by the demand for yet more power out of a shrinking volume envelope. It all started with Jobs (let's blame Steve; we do for everything else that goes sideways) tossing a prototype iPod into an aquarium, seeing the bubbles, demanded that said air spaces be eliminated. "Make it smaller."

You can't "alternative facts" your way around the asymptote.

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