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Comment Re:There was nothing to catch (Score 1) 155

Much like testing for certain medical diseases, sometimes you can only determine a cause by exclusion.

  • A phone that is turned off is consuming no power, so the failure cannot plausibly be caused by an excessive rate of discharge or by external heat (e.g. being too close to a hot GPU).
  • A phone that is not charging is adding no power to the pack, so the failure is probably not caused by an excessive rate of charge or by overcharging.
  • Multiple battery manufacturers use different battery chemistry and different designs, so the failure cannot plausibly be caused by dendrites or other similar failures. Also, the failures don't occur with those same batteries in other devices, which eliminates the batteries themselves as a likely cause.

When you eliminate the impossible, what remains are failures that can occur even with a battery that is neither charging nor discharging. The most likely causes, then, involve some form of physical damage.

LiPo packs change size during normal charging and discharging just a bit. That's why there are tolerances build into the design. With insufficient tolerances, bad things happen (TM), and even if the tolerances are sufficient to avoid self-puncturing at their maximum size, it is possible that flexing the case in just the right way while the pack is maximally swollen could still puncture the pack. So this is at least a plausible explanation, whereas most other theories aren't.

With that said, even if we assume that these folks are correct, it does not absolve other aspects of the design. Not all failures have only a single root cause. For example, IIRC, overcharging a LiPo pack can cause unusual levels of battery expansion from hydrogen buildup, which when combined with normal levels of flexing in a case that has insufficient tolerances, would result in the pack perforating and venting with flame.

Comment Re:!Revolution (Score 5, Funny) 263

The word revolution also contains the word evolution, and you might have noticed that we've evolved past the point of calling a paper printer a necessary component of computing today.

And the word "internet" contains the word "tern", so clearly it is built upon angry arctic birds with sharp beaks that dive bomb anyone who gets too close to their nesting grounds.

Comment Re:because (Score 2) 263

Indeed. I've ordered 3d prints online several times and as things stand there is no reason I'd ever do otherwise. The choice is, "have something produced using top notch hardware and finished by professionals", or "have something produced by crappy hardware, by you". The marginal cost may be lower if you do it yourself, but you have to plop down $1k first, so unless you 3d print a lot, you don't win even on that comparison. It's just not worth it.

If you run a business where you're 3d printing prototypes every day, that would be different. But regular for home users, I just can't see an argument for it.

Comment Re:It's always cost (Score 4, Interesting) 263

That's really a key issue. Most "standalone" things people want are not made of plastics, except for toys. There are a some things - for example, parts for a small homemade drone or whatnot, where strength is not important but lightness is. But most often, if you want something "standalone", you want it out of metal.

Being able to print replacement plastic parts for other things could be nice, mind you. For example, I've twice had to replace a plastic part on my refrigerator and it cost something like $50 each time with a nearly month delay, due to customs fees, shipping to where I am, etc. Having been able to print one out would have been great. Except, having a 3d printer alone wouldn't have been enough, because there's no "universal spare part database" that manufacturers upload to. A 3d scanner as well might have been able to enable reproducing the part from scanning its broken pieces, except that not only do you have to have one, the part was transparent, and many 3d scanners don't like transparent objects.

A "3d printing revolution" may come some day. But things are a lot more complicated than just making it possible to print something out of some material.

Comment Re:They only show gorgeous women (Score 2) 241

Please ignore the correlation between "looks" and genetic indicators of reproductive health

That would be a nice argument if there was some universal agreement on what is attractive. In some cultures, thin is attractive. In others, fat. Some places like women who stretch their necks out. Others like their feet bound to the point that they can hardly walk. In Meiji era Japan, it was seen as attractive for women to paint their teeth black. Do you find that hot? There is no single standard of beauty. You cannot just declare yours to be universally applicable.

The majority of "beauty" traits have nothing to do with genetic indicators of reproductive health. That said, there are some. For example, for both sexes, "clear skin" is usually desirable, as that is an indicator of immune system fitness. And of course standard secondary sex characteristics, including having typical voice ranges appropriate to their sex, muscle mass in men, in women breasts and wide hips, etc. But the majority of the specific details that make up the "look" of an attractive man or woman versus other men and women in their society are simply cultural.

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