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Comment: Re:Extraordinary claims... (Score 1) 227

by robot256 (#46694277) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds

Ah, I see: http://en.wikipedia.org/wiki/P... "A pseudocapacitor has a chemical reaction at the electrode...This faradaic energy storage with only fast redox reactions makes charging and discharging much faster than batteries."

So, they made a new kind of supercapacitor, maybe with lower self-discharge than previous ones? A supercapacitor is exactly what I would expect in this application. Calling it a battery seems unnecessary and misleading.

Comment: Re:Giga market play (Score 2) 151

by robot256 (#46688667) Attached to: Tesla: A Carmaker Or Grid-Storage Company?

Fact: The U.S. power grid has continually reduced its overall emissions for decades now.

Fact: Electric vehicles produce less overall emissions than a 35mpg car, even on the dirtiest grid in the U.S, and most EVs are operated on much cleaner grids.

Fact: Over 1/3 of EV drivers own enough solar generation to offset the power used in their cars, making them truly zero emissions.

Zero-emissions electric vehicles exist now, if you have the money or lifestyle to fit it. I too think it will be a great day when hydrogen cars actually compete with battery-electric vehicles. But the obstacles we have to solve before then are many:

1) invent a way to convert electricity into hydrogen that actually approaches the efficiency of batteries, if not equaling it, instead of making it out of methane like we do now or wasting half your power in electrolysis.

2) build hydrogen fueling stations everywhere before a solid base of users exists to pay for it.

3) convince the public that hydrogen cars won't explode like the Hindenburg (stupid but important).

4) make them cheaper than an equivalent battery-electric car, because by the time all that gets done BEVs will be so far ahead you will wonder why you bothered with hydrogen at all.

Once Tesla has created a super-cheap source of grid storage batteries, everyone with an electric car can get solar and go off the grid. Then the power plants and centralized distributors will be forced to shut down. Then local grids will spring back up so people can use communal backup generators on cloudy weeks, but we will never again need the complex monstrosity of our present power grid because all generation will be local. We already have new factories installing enough solar and wind to power themselves, so it's only a matter of time before the grid becomes redundant and uneconomical to maintain.

Comment: Re:Panasonic (Score 1) 151

by robot256 (#46688435) Attached to: Tesla: A Carmaker Or Grid-Storage Company?

Not to mention, batteries for cars are are optimized for weight, while batteries for grid power are optimized for everything but weight.

Batteries for cars are optimized for weight, size, power delivery, low maintenance and cost. Batteries for grid storage are optimized for power delivery, low maintenance and cost. Size and weight are bonuses that make them cheaper to deploy (less land/manpower). So they really aren't as different as you make out.

No utility in their right mind is going to deploy billions of lead-acid cells that will need constant watering and replacement in 5 years when they could buy EV batteries cheaply (due to combined scale of manufacturing and/or reuse) and leave them in place for 20 years.

Comment: Re:Extraordinary claims... (Score 1) 227

by robot256 (#46688251) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds
It's not clear to me how those two things could be put together in the way they describe and do what you describe. If what you say is the case, then the capacitor has the same capacity as the battery, and if they can do that without making the capacitor 10x bigger than the battery, then their breakthrough is actually "ultra-high-energy-density capacitors" and not "fast-charging phone batteries". In that case, there are way more lucrative markets for that than quick-charging phones, and their choice of demo makes me think they were going for a quick youtube sensation and not an actual tech advertisement.

Comment: Re:Something fishy.. (Score 1) 227

by robot256 (#46685283) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds
Yes 2000mAh will charge in one hour at a rate of 2 amps, and charge in 30 seconds at 240 amps. But the cell phone battery is 3.6 volts and 3.6*240 is only 864 watts, much less than the 1800 watts delivered by an extension cord. Assuming they deliver that to a DC-DC converter in the battery at 48 volts on the banana plugs they only need 18 amps, but that is still a lot. I still think the whole thing is cold-fusion-style vaporware.

Comment: Re:Phones yeah (Score 1) 227

by robot256 (#46685165) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds
Actually, drag is the most important issue on long trips. Mass is less of an issue in EVs because you can recapture 60% of your kinetic energy when you brake, and mostly a non-issue when driving at a constant speed on the highway. Adding lithium batteries to a car without increasing the drag profile invariably increases the range.

Comment: Re:Phones yeah (Score 1) 227

by robot256 (#46685093) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds

Existing batteries can charge to 80% in half an hour. The only thing stopping us is the scarcity of high-power charging stations, and making batteries charge faster only makes those stations more expensive and less likely to be actually installed. That is why improving battery capacity and efficiency, not the charge rate, and rolling out more infrastructure using the existing standards are the most important things for EVs right now.

Comment: Re:Phones yeah (Score 1) 227

by robot256 (#46685043) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds
There's a pretty big continuum between 2 minutes and overnight. Existing EV batteries can charge in half an hour at a suitable fast-charger station with a manageable cable assembly. Making them charge faster simply doesn't help because it (a) does not solve the problem of needing expensive high-power chargers everywhere, and (b) creates a new problem because you need ridiculously high voltage and/or current capacity in all the charging cables.

Comment: Re:Phones yeah (Score 1) 227

by robot256 (#46684919) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds

They aren't looking at charge swaps because the infrastructure cost is enormous. Better Place tried it in Israel (much smaller country with more political incentive for EV use) and went bankrupt because people really didn't need swaps as much as they thought they would, and because they could only get one model of car to use the compatible battery.

It's hard enough getting people to roll out the standard charging stations we have now and keeping them all operational, can you imagine getting 100x that investment before anyone even buys the cars? Now think about covering a country as big as the US with gas-station-sized underground robotic battery swapping facilities and keeping them all stocked and operational.

And since you will only have as many customers as you have buyers of compatible cars, to make the network viable you need lots of models using the same battery. We only barely managed to standardize the stupid plug, can you seriously imagine them agreeing on a fundamental part of their cars' chassis?

Battery swapping is a logistical nightmare. Sure, we could do it, but we could also build a base on the moon and rid the world of famine if we really wanted to, but we won't. Fixed 200-mile batteries and 10- or 20-minute superchargers are the most realistic way to go. (Tesla's superchargers work just fine without 00 gauge cables.)

Comment: Extraordinary claims... (Score 2) 227

by robot256 (#46684659) Attached to: Nanodot-Based Smartphone Battery Recharges In 30 Seconds

Am I the only one skeptical of whether this is real or not? What they describe doesn't make a lot of sense to me:

On one side it acts like a supercapacitor (with very fast charging), and on the other is like a lithium electrode (with slow discharge). The electrolyte is modified with our nanodots in order to make the multifunction electrode more effective.

So is it a battery or a capacitor? Maybe I'm just woefully ignorant of how lithium batteries work, but I was under the impression that it was the surface area of the electrodes and the activity of the electrolyte that govern the internal resistance, and hence the charge rate. Capacitance has nothing to do with it, unless you are charging up a capacitive "buffer" that drains into the chemical battery more slowly afterward, but that seems kind of pointless.

Pulling out buzzwords like "environmentally friendly" materials and nanodot "self-assembly" doesn't really help your plausibility, either. Anybody can make a box with banana jacks and an app with a timer in it.

Comment: This is how they develop CPR training (Score 4, Interesting) 162

by robot256 (#46684449) Attached to: Judge (Tech) Advice By Results

In recent years at least, this is precisely the method they have used to develop CPR training for the general public. Even if a more complicated routine would result in a better chance of survival in any given case, they have to make the rules simple enough that people can remember and apply them years later and under stress. This increases the statistical survival rate overall, which is exactly the point.

But agree with everyone else, you could have explained this to a mildly intelligent person in about 1/4 of the words.

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