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Comment It's easy for men (Score 4, Insightful) 502

2 pairs of nice shoes for suits (one brown, one black), 1 pair of boots for heavy weather, 3 pairs of sneakers, 1 pair of running shoes. Done.

Also, having multiple pairs of shoes makes them last longer: wearing the same pair every day runs them into the ground faster than alternating between a few.

But more importantly: a fashion poll on Slashdot?

Comment Re:Cold Climate? (Score 2) 362

Electrolyte of Li-ion battery completely freezes somewhere around -30C. Degradation of performance (i.e. increase in resistance of the electrolyte and subsequent decrease of available power) starts sooner, but there are additives for that.
I guess there are few places on earth where a roadster is left parked for an extensive period of time in order for the whole pack to freeze.

Comment Re:Tow? (Score 4, Interesting) 362

Well technically towing an electric vehicle, missing a clutch, would make it a generator, which could possibly damage the battery. However there is a youtube video showing a Nissan Leaf being towed and the battery being recharged. Don't try this at home!

Another option with the Tesla could be to lift the back wheels and tow it with the front wheels on the ground, unless there is some regenerative braking system which still acts as a generator. And yes, you want to lock the wheels if you do that.

Comment Summary is right, BMS is probably the cause (Score 3, Interesting) 362

When I read the blog article I thought exactly the same thing. Cells left to self-discharge will not go below their thermodynamic equilibrium, which is more or less the potential at which they are built (remember, Li-ion batteries when assembled are discharged by nature). There is no danger of damaging the cells when self-discharge occurs.
Another issue is when the cells are actively overdischarged, however a Li-ion battery is more likely to explode due to overcharge (plating of Li metal at the negative electrode) than overcharge (insertion of too much lithium in the cathode and electrolyte depletion).

Most likely the BMS is refusing to come back to life unless hooked up to a secret Tesla computer, but I guess the packs can be refurbished.

Also, kudos to the idiot recharging the car with a 30m cable extension (that's what 100 feet is, right?).

Comment Re:How much energy? (Score 4, Informative) 114

Interesting, but how much energy does it take to run this thing?

From the abstract: "Here, we demonstrate an energy consumption of 0.29 Wh lâ"1 for the removal of 25% salt using this novel desalination battery, which is promising when compared to reverse osmosis ( 0.2 Wh lâ"1), the most efficient technique presently available."

Submission + - Swiss goverment finds piracy does not decrease the (admin.ch)

Jack Malmostoso writes: The Swiss government finds that while a large percentage of the population downloads media content illegally, the total income used for entertainment remains steady.
Instead of spending the money in CDs and books, the Swiss consumers visit movie theaters and go to concerts more often, thus supporting adequately the industry.
For this reason, there is no need to intervene at the legislative level, concludes the Federal Government.

Story not available in English, google translation from French here:

http://translate.google.com/translate?hl=en&sl=fr&tl=en&u=http%3A%2F%2Fwww.news.admin.ch%2Fmessage%2Findex.html%3Flang%3Dfr%26msg-id%3D42415

Comment Re:For one battery that goes, billions are just fi (Score 1) 277

Good question. Short answer, I don't know for sure.
Long answer, see below.

For batteries packaged in an aluminum can, I can't see a big impact. For batteries packaged in a soft pouch (such as the iPhone's, I believe) it might be more of an issue.
The point of the problem is the liquid electrolyte, which is generally formed by two main solvents, Ethylene Carbonate and Dimethyl Carbonate. EC is a solid at room temperature (mp around 36C), while DMC is a liquid with a reasonably high boiling point (90C IIRC).
I don't think that the reduced pressure in the aircraft is enough to make so much DMC evaporate as to create excessive pressure in the packaging. Which is however designed to fail if too much pressure is built up, and Li-ion batteries are assembled in the discharged state.

Comment Re:For one battery that goes, billions are just fi (Score 1) 277

Exactly what is the difference between a no-name Chinese battery, and a named Chinese battery, besides cost?

In Japan and South Korea battery production is almost fully automatic and conducted in well controlled conditions. This is a continuous process in which a long sheet of electrode material is assembled in a roll.
In China, on the other hand, many batteries are produced by hand by stacking discrete smaller sheets of electrode, then putting the stack in a container (be it an aluminum can or a soft pouch). You can imagine that this stacking can be less than perfect and a shortcircuit due do misalignment or some foreign body is always possible.
Of course not all batteries are produced this way, but some are.

Comment For one battery that goes, billions are just fine (Score 5, Interesting) 277

Between this, the Volt battery going up in flames and on a smaller scale the Belgian Post e-bikes catching fire, I am very worried about the fast deployment of Li-ion batteries in many fields.
I am a researcher in Li-ion batteries, and I know how dangerous those little buggers can be, but also how many efforts are done to make them safer. However, you can't take bad manufacturing out of the equation, and you should always ask yourself why a no-name chinese battery costs 1/3 of the original battery.

It would be nice to know if the phone was ever dropped, or its battery replaced at any point, or if a non-standard charger was used.

Comment The idea is good, but email still has its place (Score 5, Insightful) 601

I agree that most emails are useless (starting from those which are sent just FYI, but are still distracting and interrupting the workflow).
However, if there is one thing I learnt by working in a megacorporation, is that _everything_ has to be in writing at some point.
So many times a colleague or supplier will say "sure, we'll do that no problem" and then weeks go by, without anyone remembering.
For accountability, email is still the way to go.

Comment Just reached a decent compromise on my machine (Score 3, Insightful) 237

Debian Sid introduced Gnome 3 a couple of weeks ago and I had a bit of a tough time to come to terms with it, but now I have reached a good compromise by installing tint2 and the alternate menu extension (which basically brings back the switch off menu item).
I'm rather pleased with this setup and the only thing I am really missing are a couple of applets, but nothing major.

Or, as other have said, XFCE is a great alternative, especially if you NEED external outputs (which gnome-shell still miserably fails to manage properly).

Comment Re:Looks like it was... (Score 0) 156

I might be taking this a little to personally, but anyway, ha-ha funny but now stop.

J.B. Goodenough has been one of the most prolific scientists in the last 50 years, especially in chemistry (and to think he's a physicist!).
Thanks to him we have rechargeable lithium batteries (for which he never made a penny, yay patent wars) and his work spans from magnetism to fuel cells. At 89 he is still incredibly bright and a delight to talk to.

I really hope he will get a Nobel prize before he leaves us.

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