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New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

extremetech.com

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Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#81

Uh, let's combine this with the other 3 articles claiming a 10x more long lasting battery, and we'll have a 1000x longer lasting, 2000x more powerful, 1000x faster recharging battery. I really love progress, but I've seen too many of these "N times better" articles and no actual consumption products by now. Same with these memristors, MRAM and feRAM, and 1000x faster internet.

> 1000x faster internet.

I don't know about you, but my first internet connection was 56 kbps, now I can easily buy 100 Mbps one (I don't cause 10 Mbps is good enough for me) and it would be much cheaper than what I had to pay 15 years ago for that 56 kbps, even including inflation.

Progress is here, we just don't notice (also media and inventors overhype). But in the end the progress is still happening unbeliveably fast. It's decimal order of magnitude every 5 years!

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#82

If a car battery can be made to charge to 50% capacity in about a minute with a total range greater than 60 miles or so, then a very novel solution to charging electric cars becomes possible -- induction coils at stop lights and along highways.

In the bigger cities and between them we could just connect electric cars to grid the whole time, and put energy meters in each car. Like trolleys. No need for big batteries inside the car, just supercapacitors for a few minutes worth of driving if there's some problem with the grid and you need to park safely.

I wonder if people could buy electric cars like they buy cellphones - you sign a contract with a provider, you pay X USD per month for the car and access to the grid, additionaly you have access to free regular car if you need to drive somehwere the grid doesn't exist yet(but you pay for the fuel by yourself).

The problem is infrastructure, I think.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#83
post #76

Earlier quoted context omitted.

Once you start getting into the thousands of volts, it becomes very dangerous. That stuff will arc through the air and kill you. There is a reason why we use a hundred or two volts in consumer appliances.

Not necessarily. If the connection would be unmanaged, as having the power available for drainage all the time, then you're right! ...but we have computers and all kind of complex systems now. The cable may be "empty" of that high voltage current until the cable is safely plugged in and ready. After plugging, before unleashing energy, the car's system and the power source's system may first communicate and verify the…

You have the wrong idea of how voltage works. High voltage electricity can and will kill you before the ground fault interruptor (or whatever) can kick in. It takes time to break a high voltage circuit, (on the order of milliseconds), and during that time, you will die. If the current is across your heart it's especially lethal.

If the voltage is high enough, there is no way to break the circuit anyway. The electricity will just arc across the (ionized) air, even if the computer physically disconnect it. Assuming the computer itself isn't killed by the spark, which is pretty likely. This is why linemen on high voltage lines don't even try to electrically insulate themselves when they're working with it live. Ask wikipedia:

For high-voltage and extra-high-voltage transmission lines, specially trained personnel use "live line" techniques to allow hands-on contact with energized equipment. In this case the worker is electrically connected to the high-voltage line but thoroughly insulated from the earth so that he is at the same electrical potential as that of the line. Since training for such operations is lengthy, and still presents a danger to personnel, only very important transmission lines are subject to maintenance while live. Outside these properly engineered situations, insulation from earth does not guarantee that no current flows to earth—as grounding or arcing to ground can occur in unexpected ways, and high-frequency currents can burn even an ungrounded person. Touching a transmitting antenna is dangerous for this reason, and a high-frequency Tesla Coil can sustain a spark with only one endpoint).

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#84
post #83

Earlier quoted context omitted.

Not necessarily. If the connection would be unmanaged, as having the power available for drainage all the time, then you're right! ...but we have computers and all kind of complex systems now. The cable may be "empty" of that high voltage current until the cable is safely plugged in and ready. After plugging, before unleashing energy, the car's system and the power source's system may first communicate and verify the…

You have the wrong idea of how voltage works. High voltage electricity can and will kill you before the ground fault interruptor (or whatever) can kick in. It takes time to break a high voltage circuit, (on the order of milliseconds), and during that time, you will die. If the current is across your heart it's especially lethal. If the voltage is high enough, there is no way to break the circuit anyway. The electrici…

You understood wrong my statement. Assume that you have two independent connecting channels in the same connecting tube. One is a live low-voltage channel for communication protocol and the other one is high-power (but dead in idle) pumping channel. When you plug the tube you automatically connect both channels. After that, having the info-line established, having assured that the couple has been locked & safe (i.e. insulated), both systems might then agree on opening the second high-power channel. It won't matter if it will take more than a few milliseconds to open or cut the power with the tube being in a safe coupling state. By "safe coupling state" I mean that not even the contact with the possible ionized air is allowed, the line being covered/insulated all the way. You just design the systems to not allow power to drain from the source unless it's safe. I also think that it's already time to design all the systems like that, not only the high-power car-recharging ones. This would make a difference in lives saved.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#85
post #83

Earlier quoted context omitted.

You have the wrong idea of how voltage works. High voltage electricity can and will kill you before the ground fault interruptor (or whatever) can kick in. It takes time to break a high voltage circuit, (on the order of milliseconds), and during that time, you will die. If the current is across your heart it's especially lethal. If the voltage is high enough, there is no way to break the circuit anyway. The electrici…

You understood wrong my statement. Assume that you have two independent connecting channels in the same connecting tube. One is a live low-voltage channel for communication protocol and the other one is high-power (but dead in idle) pumping channel. When you plug the tube you automatically connect both channels. After that, having the info-line established, having assured that the couple has been locked & safe (i.e.…

Google "ground fault interruptor." What are you are talking about already exists. And it doesn't solve the problem.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#86
post #58
post #53

Earlier quoted context omitted.

Minor nitpick is charge time at a supercharger would remain 45 minutes. You'd need some kind of miracle superduper charger to deliver that kind of current. A cable that can handle that kind of current would be kind of unimaginable for the average civilian. It would resemble a telephone pole. Not the wires on the pole, but the pole itself. A stereotypical thermodynamics class assignment was something along the lines o…

For those of us that didn't study thermodynamics, what is the answer that's so stunning?

Whoa am I posting late sorry.

There's a simpler way to do the analysis which doesn't require heat of combustion of typical gasoline analysis and flowrates and such. Assume it takes a KW for a horsepower (perfectly accurate for 1 sig fig) and it takes a couple horsepower (kilowatts) to go down the highway on a long road trip. To at least one sig fig this is correct. Also it takes about 3 times the chemical gasoline energy to generate electricity because IC engines are not terribly efficient. We'll call it 10 KW gas equivalent to drive on the interstate at a constant-ish high speed.

Now what fraction of the time of a road trip do you spend pumping gas vs driving? Well it can't take more than 4 minutes to fill a 10 or so gallon gas tank, and on cross country trips I can get a good 8 hours or so outta one tank, so to one sig fig I spend WAY less than 1/100th the time pumping gas vs driving.

So multiply 10 KW by 100 times the flow rate (conservation of energy and all that)

Another way to look at it, is think of the flow rate, lets say 5 gallons per minute. The kind of engine required to burn a couple gallons per minute resembles my uncle's hospital UPS backup engines, certainly in the megawatt class. This is also in the thousand horsepower (aka megawatt) class airplane engine and race car category.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#87
post #82

If a car battery can be made to charge to 50% capacity in about a minute with a total range greater than 60 miles or so, then a very novel solution to charging electric cars becomes possible -- induction coils at stop lights and along highways.

In the bigger cities and between them we could just connect electric cars to grid the whole time, and put energy meters in each car. Like trolleys. No need for big batteries inside the car, just supercapacitors for a few minutes worth of driving if there's some problem with the grid and you need to park safely. I wonder if people could buy electric cars like they buy cellphones - you sign a contract with a provider,…

Some busses have been running on this kind of wiring in cities for ages.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#88
post #87
post #82

Earlier quoted context omitted.

In the bigger cities and between them we could just connect electric cars to grid the whole time, and put energy meters in each car. Like trolleys. No need for big batteries inside the car, just supercapacitors for a few minutes worth of driving if there's some problem with the grid and you need to park safely. I wonder if people could buy electric cars like they buy cellphones - you sign a contract with a provider,…

Some busses have been running on this kind of wiring in cities for ages.

Yep, we have trolleys in my city and they work OK. Still less popular/more difficult routes are served by regular buses.

Re: New lithium-ion battery design – 2,000x more powerful, recharges 1,000x faster

#89
post #87
post #82

Earlier quoted context omitted.

In the bigger cities and between them we could just connect electric cars to grid the whole time, and put energy meters in each car. Like trolleys. No need for big batteries inside the car, just supercapacitors for a few minutes worth of driving if there's some problem with the grid and you need to park safely. I wonder if people could buy electric cars like they buy cellphones - you sign a contract with a provider,…

Some busses have been running on this kind of wiring in cities for ages.

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