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She won the $50,000 Intel Foundation Young Scientist Award

A high school student from California has created a way to charge cell phones completely in just 20-30 seconds. 

Eesha Khare, 18, of Saratoga, California, recently won the $50,000 Intel Foundation Young Scientist Award for her fast-charging device. 

The device uses an improved supercapacitor that can store a lot of energy into a small space using a nanorod electrode. It is capable of 10,000 charge-recharge cycles and can fully charge a cell phone in 20-30 seconds. 

Traditional chargers typically take hours to achieve a full charge, and are capable of only 1,000 cycles for rechargeable batteries.


Khare said her supercapacitor has been used to power an LED, and sees her invention being placed in cell phones in the future.

"It is also flexible, so it can be used in rollup displays and clothing and fabric," Khare said. "It has a lot of different applications and advantages over batteries in that sense."

This definitely isn't the first time a high school student has come up with a brilliant invention in recent years. Just last year, 15-year-old Jack Andraka invented a new pancreatic cancer test that earned him the $75,000 prize from another Intel-sponsored fair. 

Source: NBC News



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RE: Paper
By EricMartello on 5/20/2013 9:50:11 AM , Rating: 3
quote:
Here's her 'more detailed' paper about it:


Thanks for doing Tiffany's job for her. Maybe DT will cut give you a kickback?

quote:
So in short, she improved a Supercapacitor by using a nanorod elecrtode to hold more storage (20Wh/kg), similar to a battery according to her (Li-Ion have 200Wh/kg, so still a long way to go), but better than current mass produced supercapacitor technology (5-10 Wh/kg).


Electrical storage capacity should be expressed as amp hours and the nominal voltage of the cell should also be included. Watt/hours is a misleading term invented by marketers who wanted to make laptop batteries seem better than they actually are.

When you know the amp/hr capacity of a battery you also have an idea of its charge and discharge rate. You can safely charge certain batteries at 5C, meaning 5 times their capacity. For a 1 amp/hr battery you could recharge it to about 85% capacity in about 20 minutes at 5C.

The problem with modern batteries like lithium polymer is that they're sensitive to overcharging, and can explode if their charge rate is incorrect. On the flipside they have a pretty good power density in a practical form that you can use today.

Nano battery technology may eventually grow some legs but I am not aware of any prototype that demonstrates practical efficacy.

quote:
All in all, it's impressive what she did at such a young age (probably with a lot of help, how else can she have the tools and knowledge to produce it), but it's not what Intel or the media wants to tell us. Such 'inventions' happen daily at Universities and no one reports about them.


Look at the last line of the paper you linked to - pretty much says it all. I do not think she deserved a $50K award for basically presenting the work of a university research team as her own. As I said in my other post, this contest is a sham and an effective publicity stunt.

What bothers me is that there are genuinely smart kids who don't get coddled by a university like she did and never really get a chance to develop their abilities because K-12 in the USA is pretty much garbage. I could go into a rant about how badly fcuked our school systems are now due to unions, districts and liberals...but I need some coffee.


RE: Paper
By karimtemple on 5/20/2013 9:56:44 AM , Rating: 2
.....Um..... it says she used their lab equipment.


RE: Paper
By maugrimtr on 5/21/13, Rating: -1
RE: Paper
By BRB29 on 5/20/2013 9:57:00 AM , Rating: 3
exactly, even if you have a cheap crappy lithium ion battery at only 100wh/kg. The best that capacitor do is 20% buffer at the same weight as the battery. 20-30 secs charge is impossible.

If there is a battery that can charge that fast, it would probably cost more than a phone and wouldn't need a capacitor. I think Intel just wanted a female winner. The other 2 winners are much more impressive.


RE: Paper
By karimtemple on 5/20/13, Rating: -1
RE: Paper
By BlazzedTroll on 5/20/2013 11:02:15 AM , Rating: 3
There what is?

"Eesha Khare, 18, of Saratoga, California, recently won the $50,000 Intel Foundation Young Scientist Award for her fast-charging device. "

"...recently won the $50,000 Intel..."

"...won..."

I don't care if they call her a "runner-up" that is not what we are worried about her. We (me and everyone else posted except you) are interested in how she won $50k for essentially doing nothing. She did win the $50k.

She did not "create" a novel super capacitor. There has been nothing posted here in this article or in the original post to indicate that she herself actually layered some materials together. Even then, http://www.wikihow.com/Build-a-Capacitor... BOOOM! how to a make a capacitor. Was that so hard. Just in case you weren't following. http://lmgtfy.com/?q=How+to+make+a+capacitor

That is how easy it is. And that would be if we had any proof that she made the capacitor herself. Which, we don't. The only one who sounds "stupid" is you.


RE: Paper
By karimtemple on 5/20/2013 11:55:44 AM , Rating: 1
Tell me why Intel chose to give her an award she didn't deserve.


RE: Paper
By BRB29 on 5/20/2013 11:58:46 AM , Rating: 5
PR


RE: Paper
By karimtemple on 5/20/13, Rating: -1
RE: Paper
By BRB29 on 5/20/2013 12:06:33 PM , Rating: 2
and who is trying to get into the cellphone business?

It's clear her work did not contribute a step forward to anything because it's already been done.


RE: Paper
By karimtemple on 5/20/13, Rating: -1
RE: Paper
By UpSpin on 5/20/2013 12:47:20 PM , Rating: 3
no, it hasn't been done yet.
The technology of SC was available already, but you can build a SC out of different materials. And she used one, which wasn't used in the past.
So she did create something new, just accept it.

Just like High Temperature Superconductors. They exist, but you can improve them. And once you found a better HTSuperconductor your work will be worth a scientifical paper and depending how much better it is even a price.

(Of course her research is nothing revolutionizing, and I also think this discovery is barely worth the price and a lot is just PR, especially the news don't understand what she actually did and overstate her research, but also consider her age and what she wrote in her original paper)


RE: Paper
By BRB29 on 5/21/2013 12:32:28 PM , Rating: 2
Upspin,

Other people here along with myself is arguing that she did not do this work, which is true. There is a link here that proved that. She simply took credit for it while a bunch of people with PhD did it. Her abstract that she wrote didn't even look like she understood what she was talking about.

At least we can both agree that her results are not spectacular. SC in that range of capacitance is already available. There are many people that proved in labs that their SC works better. Some of them are extremely cheap to make.

this is why people raise the BS flag on her winning the competition. It's a PR stunt and I hope we can all agree to that. The girl doesn't even understand the work she supposedly did for God's sake.


RE: Paper
By karimtemple on 5/21/13, Rating: -1
RE: Paper
By Stuka on 5/20/2013 2:48:03 PM , Rating: 4
Search of Google shows us this:
http://research.pbsci.ucsc.edu/chemistry/li/public...

A research paper, published 15 months ago, which includes Dr. Yat Li as the author, regarding hydrogenated TiO2 supercapacitors. Basically, she stood beside him as he demonstrated an application for research he has already done.

So, what we have here is a child who showed great interest in a part of science; assisted an established researcher and likely showed a capacity to understand the work; thus earning an award in the hopes of inspiring her to continue as well as inspiring other young folks to follow her, and generating positive spin for Intel.

It's anti-climatic, but it is, in fact, win-win-win.


RE: Paper
By EricMartello on 5/20/13, Rating: 0
RE: Paper
By BRB29 on 5/20/2013 10:26:49 AM , Rating: 4
quote:
Pretty much this. Liberals' idea of diversity - anyone who's not a white, American male


The winner actually is the only person that fits the white male description.


RE: Paper
By EricMartello on 5/20/2013 10:52:36 AM , Rating: 2
quote:
The winner actually is the only person that fits the white male description.


Haha...well played.


RE: Paper
By BRB29 on 5/20/2013 2:15:22 PM , Rating: 2
Kelso: BURN!!!!
lol


RE: Paper
By karimtemple on 5/20/13, Rating: -1
RE: Paper
By BlazzedTroll on 5/20/2013 11:11:52 AM , Rating: 5
I hope at this point you realize that I had to make this account just to come reply to each of your posts. It was bothering me that you thought you were qualified to have any say here. Everyone else has posted 50 line comments with quotes from other articles backing up their statements. You just wait for them to say something and then say "NO". It is so funny to me that you would think anyone is reading your comments and agreeing with you. LOL. You are an idiot.

SHE DID NOT CHARGE A CELL PHONE IN 30 SECONDS. She lit an LED with a capacitor. I could literally make a capacitor and an led from shit laying around my house and light it up. You feel trapped because you simply cannot engage in intellectual conversations. Your posts are severely lacking. Being in the same world as people like you is the real problem. People who think they are intelligent and know what's going on, when really you just got spun around 5 times and tried to put your fingers on the keyboard like some weird version of pin the tail on the donkey.


RE: Paper
By karimtemple on 5/20/13, Rating: -1
RE: Paper
By BRB29 on 5/20/2013 12:04:46 PM , Rating: 3
You're right, it only takes you 5 lines to be a troll


RE: Paper
By Cheesew1z69 on 5/20/13, Rating: 0
RE: Paper
By StanO360 on 5/21/2013 1:36:11 PM , Rating: 3
The question is not how fast it charges which should be fast as it's a capacitor not a battery. But what is the cost of controlling its discharge rate (which would naturally just dump), heat, efficiency loss.


RE: Paper
By UpSpin on 5/20/2013 10:22:06 AM , Rating: 2
Wh isn't misleading. It's also not W/h, but Wh. The same it's Ah and not A/h. There's no need to specify both U and I if you can put it in one more handy value, P.
When you know the Ah of a battery you still don't know how fast you can recharge it, some faster, some slower, depending on the technology. Just current technology lies around 1C-5C, but that's just a current limit and not a limit of future batteries.
And btw., we're talking about supercapacitors, which don't have such a limit at all. They get charged with a constant voltage and take what their internal resistance allows. They can't explode and you don't need a charge controller. You set it to a fixed voltage and give it whatever Ampere it wants.


RE: Paper
By BRB29 on 5/20/2013 10:33:41 AM , Rating: 3
Yes it is misleading. Charging a battery in 20-30 secs is impossible for her SC.

Even in theoretical math, it wouldn't work. Unless the SC has the same energy as the battery, which it doesn't, there is no way to achieve the full charge.

You can say future batteries can charge faster. I can say future batteries have much higher capacity which would make her SC useless. Her lab result is only a little better than cheap mainstream SC.


RE: Paper
By UpSpin on 5/20/2013 12:00:38 PM , Rating: 1
she never claimed that a battery will charge faster thanks to her SC.
She only claimed that she used a different electrode material which offers superior capacity compared to current SC. As a use case she demonstrated that once such a SC gets put inside a smartphone instead of a chemical battery you'll be able to recharge it in no time.

In a video she explained it to a reporter, which, sadly also shows she has no idea what she's talking about (comparing the size of her SC and implying it has the same capacity as a current Li-Ion battery found in a smartphone).

But regardless of that, she never tried to improve the charge time of chemical batteries, never, ever!


RE: Paper
By BRB29 on 5/20/2013 12:20:47 PM , Rating: 5
Given her current density, it would take an SC the size of 3-4 smartphones to have the same energy storage as mainstream Lithium batteries in smartphones today. I don't think I want a walkie talkie just to charge in 30 secs.

In neither scenario, she successfully demonstrated anything even in lab form.


RE: Paper
By Mint on 5/20/2013 3:43:42 PM , Rating: 2
You're misinterpreting her work.

She never said she can charge a battery in 20-30 sec. She said that her super capacitor can be charged that fast. That either means:
A) you put a smaller battery in the phone that can be charged instantly
B) improve on the tech until it doesn't have to be smaller
or C) have a hybrid so that when you run out of battery, you stick it in a plug for 30 seconds to get 10% capacity

10% is enough for several hours of standby and short calls, and much better than having a dead battery because you forgot to charge or bring a spare.


RE: Paper
By EricMartello on 5/20/2013 10:48:45 AM , Rating: 2
quote:
Wh isn't misleading. It's also not W/h, but Wh. The same it's Ah and not A/h. There's no need to specify both U and I if you can put it in one more handy value, P.


W/h is misleading because it's irrelevant. A battery has a nominal voltage. Current is drawn from the battery at its nominal voltage, up to and sometimes exceeding its amp/hour rating.

quote:
When you know the Ah of a battery you still don't know how fast you can recharge it, some faster, some slower, depending on the technology. Just current technology lies around 1C-5C, but that's just a current limit and not a limit of future batteries.


Incorrect. All modern rechargeable batteries can change at a rate of at least 1C. Whether or not they can go above that depends on their chemistry and construction. Also, at 1C, you will need a minimum of 1 hour to charge a given battery.

quote:
And btw., we're talking about supercapacitors, which don't have such a limit at all. They get charged with a constant voltage and take what their internal resistance allows.


Voltage is the flow rate of current. A charging capacitor still draws current, and it can draw quite a bit if you have nothing regulating the current, such as connecting a battery directly to a capacitor.

The capacitor will charge UP TO the voltage of the battery or its internal limit. If its internal voltage limit is exceeded it tends to go POP.

quote:
They can't explode and you don't need a charge controller. You set it to a fixed voltage and give it whatever Ampere it wants.


Supercapacitors tend to be low voltage so you would need to regulate the voltage it receives or it can damage the capacitor.

Doesn't change the fact that you would need to feed it a quantity of electricity (amps) for a given time at its rated voltage to charge it to capacity.


RE: Paper
By BRB29 on 5/20/2013 11:18:11 AM , Rating: 2
Eric,

karim does not even know how capacitors or batteries work. At this point, I believe he is trolling.


RE: Paper
By karimtemple on 5/20/13, Rating: 0
RE: Paper
By BRB29 on 5/20/2013 12:01:16 PM , Rating: 2
you have credentials?
sounds like you have a love story with your ego

...still a better love story than twilight though


RE: Paper
By MrTeal on 5/20/2013 11:30:27 AM , Rating: 3
quote:
Incorrect. All modern rechargeable batteries can change at a rate of at least 1C. Whether or not they can go above that depends on their chemistry and construction. Also, at 1C, you will need a minimum of 1 hour to charge a given battery.

That's not correct. Generally, batteries that are more energy dense for a given chemistry have much slower charge and discharge rates. Compare the Panasonic UR18650ZTA and the UR18650SAX.
http://www.panasonic.com/industrial/includes/pdf/U...
http://www.panasonic.com/industrial/includes/pdf/U...
Same manufacturer and basic chemistry, but one can be discharged at 8C without affecting the final capacity much but another starts to quickly lose capacity even discharging at 1C.

The extreme example of this are high capacity rechargeable lithium coin cells, where a 3032 sized cell can have a 100mAh capacity, but won't be able to charge or discharge more than 1mA.


RE: Paper
By EricMartello on 5/20/2013 1:12:06 PM , Rating: 2
quote:
That's not correct. Generally, batteries that are more energy dense for a given chemistry have much slower charge and discharge rates. Compare the Panasonic UR18650ZTA and the UR18650SAX.


Yes, they would, if you think of the batteries as buckets the bigger the bucket the longer it takes to fill or empty it using a fixed flow of water. It's not necessarily that they charge or discharge at different rates, it's just that a larger capacity takes longer to fill and lasts longer under load.

quote:
Same manufacturer and basic chemistry, but one can be discharged at 8C without affecting the final capacity much but another starts to quickly lose capacity even discharging at 1C.


One battery is 1350 mAH and the other is 3000 mAH; the larger capacity battery does not experience as much of a voltage drop under load as the smaller battery does, but that doesn't really counter what I said.

All I said is that you can charge any modern rechargeable battery at 1C, with the implication being that it is safe to do so. You will not "lose capacity" but your battery may not be suited to a high-current application.

Some batteries do a better job of maintaining their nominal voltage rating under load than others. Certain batteries can be damaged if you let their voltage get too low - but that is beside the point.

In general, a higher capacity battery will have higher tolerances for current in both charging and discharging cycles, but 1C is going to be a safe charge or discharge rate and your links support that statement.

quote:
The extreme example of this are high capacity rechargeable lithium coin cells, where a 3032 sized cell can have a 100mAh capacity, but won't be able to charge or discharge more than 1mA.


If the battery you were referring to is the only one of its kind them maybe you'd be right, but check this link below:

http://www.eemb.com/pdf/Li-ion/LIR3032.pdf

Note the "max current" for charge and discharge...but also consider that an application where 100 mAH @ 3V is sufficient would typically not incur high current draw nor would it require a rapid charging cycle.


RE: Paper
By MrTeal on 5/20/2013 4:38:43 PM , Rating: 2
quote:
Yes, they would, if you think of the batteries as buckets the bigger the bucket the longer it takes to fill or empty it using a fixed flow of water. It's not necessarily that they charge or discharge at different rates, it's just that a larger capacity takes longer to fill and lasts longer under load.

You're missing the point, the battery makers tailor the geometry of the battery to optimize for high current draw or high capacity.

quote:
One battery is 1350 mAH and the other is 3000 mAH; the larger capacity battery does not experience as much of a voltage drop under load as the smaller battery does, but that doesn't really counter what I said.

The larger capacity battery exhibits more voltage drop at high currents; a higher internal resistance is one of the trade-offs they make to get the higher capacity. Look at the discharge graphs, the high capacity ZTA has almost a 250mV drop between the 0.2C (0.6A) and the 1C rate (3A), while the low capacity SAX has only about a 100mV drop between the 0.2C (0.27A) and the 2C rate (2.7A). That's why if you pop open the battery pack of a Lithium power tool they all use high current, low capacity batteries instead of the really high capacity 18650s you can buy.

quote:
All I said is that you can charge any modern rechargeable battery at 1C, with the implication being that it is safe to do so. You will not "lose capacity" but your battery may not be suited to a high-current application.

That is the main point of what I'm getting at, not every modern battery can be charged at 1C. Standard Lithium Ion and LiPo ones you can, but there are modern chemistries used for different applications that can't be charged safely in an hour. It's a blanket statement that's not correct. You linked to a Lithium ion CR3032 that could be charged or discharged at 1C, I linked to one that cannot. Your blanket statement of "any modern rechargeable battery at 1C" is wrong.


RE: Paper
By EricMartello on 5/20/2013 6:43:46 PM , Rating: 2
quote:
You're missing the point, the battery makers tailor the geometry of the battery to optimize for high current draw or high capacity.


You disagreed with my generalized statement about 1C being a safe charge rate for modern rechargeable batteries, then you found some batteries that you thought would support your idea - but they did not.

You are right, 1C may not always be the OPTIMAL charge rate but it's safe to say that it's VIABLE.

quote:
Look at the discharge graphs, the high capacity ZTA has almost a 250mV drop between the 0.2C (0.6A) and the 1C rate (3A), while the low capacity SAX has only about a 100mV drop between the 0.2C (0.27A) and the 2C rate (2.7A).


Despite this, they both remain within 200 mV of their nominal rated voltages for at least half of their respective capacities...but this isn't what I was talking about.

At which point do you demonstrate where a 1C charge or discharge rate would be unsafe for either of these batteries? You seem to be hung up on the difference between 'optimal' and 'viable'.

quote:
You linked to a Lithium ion CR3032 that could be charged or discharged at 1C, I linked to one that cannot. Your blanket statement of "any modern rechargeable battery at 1C" is wrong.


I'd be willing to bet money that the one you linked to could be charged at 1C even if the spec sheet says no.

I would also say that what's commonly accepted by most people as a 'rechargeable battery' is not one of these niche button cells, rather it would be a cell phone, camera battery, AA or AAA type - all of which will charge and discharge safely at 1C.


RE: Paper
By MrTeal on 5/20/2013 7:59:45 PM , Rating: 2
quote:
I'd be willing to bet money that the one you linked to could be charged at 1C even if the spec sheet says no. I would also say that what's commonly accepted by most people as a 'rechargeable battery' is not one of these niche button cells, rather it would be a cell phone, camera battery, AA or AAA type - all of which will charge and discharge safely at 1C.


Actually, you're right there. I thought I'd inserted a link to the 100mAh coin cell I was talking about, but I obviously missed it.
http://www.panasonic.com/industrial/includes/pdf/P...
A button cell is hardly niche, there's billions of them made each year. They're just tailored to a different market, low self discharge and high capacity in a small size without a need for much current draw.

1C isn't some magic number, it's just that rather than choose to list energy storage in joules or some other unit, they settled on Ah. That many batteries can be charged in an hour or less doesn't grant some special physical significance to 1C.


RE: Paper
By EricMartello on 5/20/2013 11:24:53 PM , Rating: 2
quote:
A button cell is hardly niche, there's billions of them made each year. They're just tailored to a different market, low self discharge and high capacity in a small size without a need for much current draw.


What I meant by niche is that coin cells are not a common type. They're used in motherboards, clocks and compact devices that require something to preserve backup memory or whatever. Often they're installed by the factory and the consumer never worries about it until it dies, which can be years. A typical battery-powered device is going to use AA or AAA type batteries...but anyway I know what you were saying.

quote:
1C isn't some magic number, it's just that rather than choose to list energy storage in joules or some other unit, they settled on Ah. That many batteries can be charged in an hour or less doesn't grant some special physical significance to 1C.


EXACTLY! It is nothing special which is why I made my original statement in response to another poster's comment claiming that there was some wide discrepancy as to the typical charge/discharge rate for a battery.

The C in 1C refers to the capacity of a given battery in amp-hours, so 1C means 1 times capacity rating. You could have any number there to describe a particular charge or discharge current.


RE: Paper
By UpSpin on 5/20/2013 12:15:39 PM , Rating: 2
Again, it's not W/h, but Wh!
Your whole post is full of misleading stuff and it seems you haven't even read what I wrote.
Of course does a battery have a nominal voltage and specific capacity, I never denied it.

And not every modern battery can get charged with 1C. That's just wrong!
A Li-Ion battery with 3.7V and 1Ah has a energy of 3.7Wh!
So if you charge it with 1Ah for one hour, it's almost full.
The same if you put 3.7W in it in one hour it's full, too. (for example by connecting it to a 3.7V 1Ah power source)
It's nothing different, it's the same, expressed in a different unit.

Supercapacitors: Just read what I wrote! I wrote:
'They get charged with a constant voltage and take what their internal resistance allows.'
your answer:
'The capacitor will charge UP TO the voltage of the battery or its internal limit. If its internal voltage limit is exceeded it tends to go POP.'
Are you joking with me? Why should you charge a SC above it's rated voltage? Why do you connect it to a battery at all? The idea is to replace a chemical battery with a SC in future devices, nothing else. And she never claimed anything else. Just read her paper:
quote:
This work is an important initial step in introducing this new electrode material in supercapacitors to replace conventional batteries in flexible electronic devices.


RE: Paper
By EricMartello on 5/20/2013 1:28:02 PM , Rating: 2
quote:
And not every modern battery can get charged with 1C. That's just wrong!
A Li-Ion battery with 3.7V and 1Ah has a energy of 3.7Wh!
So if you charge it with 1Ah for one hour, it's almost full.


By your example, that would be charging at 1C. C equals 1 a/h in this case.

quote:
The same if you put 3.7W in it in one hour it's full, too. (for example by connecting it to a 3.7V 1Ah power source)
It's nothing different, it's the same, expressed in a different unit.


Watts are a unit of energy. We do not know how much energy there is in a battery; we calculate this based on its known capacity and voltage. Nobody who knows what they're talking about is going to be referring to battery capacity in W/H. I suppose you're one of those people who measures car engine performance in HP per liter.

quote:
Are you joking with me? Why should you charge a SC above it's rated voltage? Why do you connect it to a battery at all?


If the battery is part of the circuit and there is no other type of voltage regulation in said circuit, then the nominal voltage of the circuit will equal that of the battery. If you have a typical 12V battery and a 2V "super" capacitor, the battery will overload that capacitor.

That was in response to your comment that a super capacitor could not explode. Both a super capacitor and normal electrolytic capacitor can be damaged if you exceed their rated voltage.

quote:
The idea is to replace a chemical battery with a SC in future devices, nothing else. And she never claimed anything else. Just read her paper:


No, that's not the idea. Capacitors were never intended to replace batteries and never will, however battery technology may advance further as new designs allow them to store more energy, perhaps even generate energy by means of a chemical reaction.

It's not really her paper, is it? Not that it matters because until she has a functional prototype it's all just conjecture. She did not deserve a $50K prize for articulate speculation and theorizing - that prize should have gone to a contestant who did their own work without help.


RE: Paper
By UpSpin on 5/20/2013 2:21:05 PM , Rating: 3
My last reply to your ignorant dumb posts:
Watt is not a unit of energy . Watthour is a unit a energy . And I never used Watt/hour (W/h) as you constantly did, I always wrote Watthour (Wh). If you don't believe me, then take a look in your physics school book, or
http://en.wikipedia.org/wiki/Kilowatt_hour
https://en.wikipedia.org/wiki/Watt
quote:
The kilowatt hour, or kilowatt-hour, (symbol kW·h, kW h or kWh) is a unit of energy

quote:
The watt is a derived unit of power in the International System of Units (SI), The unit, defined as one joule per second, measures the rate of energy conversion or transfer.


So again, Wh (Watthour), because Wh is a unit of energy, gives you the amount of energy stored in a battery!

quote:
Nobody who knows what they're talking about is going to be referring to battery capacity in W/H.

I never wrote W/h, I always wrote Wh and pointed you, several times, to this fundamental mistake you constanstly did.

quote:
If you have a typical 12V battery and a 2V "super" capacitor, the battery will overload that capacitor.

Of course, if you're an idiot you can bring everthing to explode. But it's a fact, a supercapacitor does not need a charging circuit, just a constant voltage (of course the correct voltage). That's all I said. Everything else you wrote came from your wrong imagintation.

quote:
No, that's not the idea. Capacitors were never intended to replace batteries and never will

That's exactly the use case of a super capacitor: To replace a chemical battery!
They get used instead of batteries already (toothbrush, backup memory, regenerative energy storage of racing cars) and will replace chemical batteries once they get a higher energy density. (which they will: see her work, see aerogel, carbon nanotubes, ...)

quote:
however battery technology may advance further as new designs allow them to store more energy, perhaps even generate energy by means of a chemical reaction.

of course battery technology will advance further, and btw. chemical batteries (ni-mh, li-ion) store the energy chemically, they release it with a chemical reaction! You seem to be living in the medieval. (maybe you wanted to sound smart and wrote some non-sense, whereas you meant some biological batteries?)

quote:
It's not really her paper, is it? Not that it matters because until she has a functional prototype it's all just conjecture

It's what SHE wrote. It's her work! You must be really jealous.
She also build the prototype, shown in the picture of this article, produced in the lab with a Prof supervising her (of course wasn't she allowed nor able to produce it totally on her own)quote


RE: Paper
By karimtemple on 5/20/2013 2:32:11 PM , Rating: 1
Thank you for at least trying. It makes me feel a lot better that at least someone here isn't a crazy person.


RE: Paper
By HoosierEngineer5 on 5/20/2013 3:11:35 PM , Rating: 2
Agreed.

Plus, capacitors are more likely to explode if the polarity is reversed. Simply exceeding their voltage rating usually is not nearly as exciting.


RE: Paper
By EricMartello on 5/20/2013 7:20:35 PM , Rating: 1
quote:
My last reply to your ignorant dumb posts:


Aka correct and factual.

quote:
Watt is not a unit of energy . Watthour is a unit a energy . And I never used Watt/hour (W/h) as you constantly did, I always wrote Watthour (Wh). If you don't believe me, then take a look in your physics school book, or


If you're going to link to something at least read the link:

Watt: a derived unit of power ... defined as one joule per second, measures the rate of energy conversion or transfer .

Do you understand what the word "derived" means? It's a synonym for CALCULATED. That means WATT is purely conceptual. Amp/hour is the CORRECT unit to express a given battery's capacity, because without knowing the AH rating the W/H label is ambiguous.

To put this another way, you cannot determine the horsepower of an engine without knowing the torque at a given RPM.

W/H is for people like you who think there are such things as 1500W "peak power" desktop speakers for $3.

Amps are the units of electrical energy a battery has "available for transfer" and volts tell us the rate of said energy transfer. By multiplying voltage times amps you get...WATTS. WATTS UP WITH THAT!?

quote:
So again, Wh (Watthour), because Wh is a unit of energy, gives you the amount of energy stored in a battery!


A W/H can be a measure of energy consumed in an hour, as it pertains to companies in the business of selling electricity and whose pricing is based on watts used per hour.

Fortunately, batteries do not charge us a fee for transferring their energy to our devices so using W/H to refer to their capacity is wholly inaccurate.

quote:
I never wrote W/h, I always wrote Wh and pointed you, several times, to this fundamental mistake you constanstly did.


Actually its w/H.

quote:
Of course, if you're an idiot you can bring everthing to explode. But it's a fact, a supercapacitor does not need a charging circuit, just a constant voltage (of course the correct voltage). That's all I said. Everything else you wrote came from your wrong imagintation.


An "empty" capacitor that is exposed to voltage will draw current until it "fills up". The capacitor's voltage will be that of the circuit it is connected to. I don't know how to make that any simpler.

If you had a capacitor that could store enough energy to power a device like a smartphone for any reasonable length of time, it would need to draw either a lot of current for a short time or be fed a lower current for a longer time to reach full capacity.

What you seem not to get is that the capacitor's ability to charge quickly does not mean it will require a lower quantity of electricity (amps) to reach its full power.

If you had a theoretical super capacitor that had a 3.7V rating and the equivalent of 2000 mAH capacity, it would draw over 360 AMPS @ 3.7V to charge itself in 20 sec. Get it?

You would not be able to reduce the current by increasing the charge voltage without damaging the capacitor.

You could use a capacitor with a high voltage rating, which would then require that you use a voltage regulator when powering the device. A VRM would reduce the efficiency and generate quite a bit of heat.

Clearly you, the guy who desperately searches wikipedia and google just to attempt to have a discussion on this topic, is qualified to declare that I am making incorrect and/or imaginative statements.

quote:
That's exactly the use case of a super capacitor: To replace a chemical battery!


No, not really. They're more of a bridge between electrolytic caps and rechargeable batteries, but they'd fall closer to standard capacitors than batteries on the capacity spectrum.

Using capacitors to replace batteries may become possible some day, but this girl and her $50K prize will have had nothing to do with it.

quote:
chemical batteries (ni-mh, li-ion) store the energy chemically, they release it with a chemical reaction!


And I suggested that in the future, there may be batteries that are capable of generating their own energy rather than having a requirement of being charged.

It would work like this: battery "self charges". You use it and deplete it. You stop using it, battery "self charges" again. Repeat. Did I lose you again?

quote:
It's what SHE wrote. It's her work! You must be really jealous.


Now we can see who's posting incorrect and imaginary information...

quote:
She also build the prototype, shown in the picture of this article, produced in the lab with a Prof supervising her (of course wasn't she allowed nor able to produce it totally on her own)quote


She built "something"; she didn't even have a working demo on hand and the level of her contribution was never disclosed so how exactly are you going to sit there and tell us what she did and didn't do?

Facts:

- She claims her "device" lit an LED. She did not say for how long.

- She believes that the lighting of an LED somehow proves that her "device" can power cell phones. Why not test something other than an LED?

- None of the articles talking about this girl mentioned even slight technical details of what she is taking credit for, but they were quite boisterous about announcing that she "invented" something so revolutionary.

- She received access to equipment that is not typically available to high school students, giving her an unfair advantage over other entrants in the contest (sham).

Bottom line - this girl is no genius but she's smart enough to game the system and is now $50K richer.

Scientist? Not.

Con artist? Probably.

Liberal? Definitely.


RE: Paper
By DerMack on 5/21/2013 9:13:43 AM , Rating: 3
Eric you are seriously messing up SI units...

There are 7 base units, metre (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol) and candela (cd). ALL other units are derived from these. Being a derived unit doesnt make them any more conceptual than these base units.

derived units include among others these:
watt (w) unit of power, J/s or kg·m2·s-3 ;
joule (J) unit of energy, N·m or kg·m2·s-2.

Wh is basically just joules (J/s·3600s=3600J) and thus energy.
W/h would be joules per second per hour. I suppose it could be used to describe the rate of change in power output...

quote:
Amps are the units of electrical energy a battery has "available for transfer" and volts tell us the rate of said energy transfer.

SI system says amperes are units of electrical current, volts electrical potential difference. (but I get the point you were trying to make, just had to nitpick)

and for the last time, stop using W/H as watthour, it is not watt per hour, check your electricity bill if you ever get confused about the units again, seriously...

MSc


RE: Paper
By StanO360 on 5/21/2013 1:47:41 PM , Rating: 2
I use the analogy of a river. Volts being the width and depth of the river and amps the speed of the current.


RE: Paper
By EricMartello on 5/22/2013 12:26:57 AM , Rating: 1
quote:
Being a derived unit doesn't make them any more conceptual than these base units.


They are conceptual in the sense that they do not represent something that can be measured as the base units you listed do.

We can measure mass, distance and we can track time, so if we have an object with a known mass moving a known distance, we can calculate it's velocity as well as kinetic energy. Meters per second and KE (expressed as joules) are conceptual values - they express the concept of energy and motion, but neither energy nor motion themselves can serve as a basis for measurement.

These units being conceptual doesn't undermine their utility in terms of physics calculations any way - the point I was making is that using WH instead of aH to describe a batteries capacity is just bad.

Why do I say this? Watts are calculated based on the current being drawn from a source at a given voltage. When you draw current from a battery, the voltage will fluctuate inversely to the current being drawn.

If a battery maker claims 100 "watt hours" it assumes that the current draw will remain constant, and therefore you may end up with more or less "watt hours" based on the current drawn from the battery.

By correctly referring to battery capacity in amp-hours, we can infer that regardless of voltage fluctuations, a battery will provide current up to its rated amp-hour rating. If I have a 12 volt 5 Ah battery, I can draw 5 amps @ 12 volts from it for 1 hour and fully expect it to deliver...and if it doesn't I would complain to the manufacturer.

quote:
and for the last time, stop using W/H as watthour, it is not watt per hour, check your electricity bill if you ever get confused about the units again, seriously...


I will as soon as people stop referring to battery capacity in WH. lol


RE: Paper
By catmanq on 5/20/2013 11:18:06 PM , Rating: 1
quote:
Watt is not a unit of energy . Watthour is a unit a energy


You obviously have no idea watt you are talking about. Eric obviously does.


RE: Paper
By karimtemple on 5/21/2013 9:08:52 AM , Rating: 2
I really don't blame you for not understanding this; electricity is not an easy subject. You'll get no disdain from me on that front. I just have two problems:

One, talking about things you have no idea of. When I don't know about something, I just refrain from talking about it or I say "I don't know." You obviously don't understand the difference between energy and power, and yet you choose to speak on it. That's why UpSpin chose to stop responding; Eric won't understand what's being said to him.

Two, the posts in this thread in general, and the massive number of downvotes I received simply for trying to be a voice of reason and of anti-sexism, make me really sad for what dark ignorance might lurk within this site. I guess that's what I get for expecting intelligence and civility from the Internet. lol, Silly, in retrospect.


RE: Paper
By StanO360 on 5/21/2013 1:42:21 PM , Rating: 2
The term is used all the time for AC UPS's btw. When you need to calculate the the backup time a given UPS will provide based on your power usage.


RE: Paper
By redbone75 on 5/20/2013 7:26:40 PM , Rating: 1
quote:
I could go into a rant about how badly fcuked our school systems are now due to unions, districts and liberals...

So, unions, districts and liberals are the cause of our school systems' predicament, but the right wants to cut everything, including education? Please, do go on.


RE: Paper
By Dorkyman on 5/21/2013 11:26:00 AM , Rating: 2
Yes, absolutely.

Our little socialist school systems are horrible because they squash innovation. The union cares about salary, benefits, and tenure. It's why the union exists in the first place.

Competition is precisely the tonic that is needed. Attach the education property tax money to each student, and allow the parents to send the student to any school they choose. Bloated and inefficient schools will suffer, while innovative and results-oriented schools will thrive.


RE: Paper
By karimtemple on 5/21/2013 11:40:01 AM , Rating: 2
Private schools are not illegal here. Socialism does not act as a replacement for capitalism, nor vice versa. Generally, they each work best alongside the other, as evidenced by all of the most prosperous periods of the U.S. and most other economically successful nations. Your assessment seems misguided.

Unions are pretty awful, though.


RE: Paper
By EricMartello on 5/22/2013 12:41:45 AM , Rating: 2
quote:
So, unions, districts and liberals are the cause of our school systems' predicament, but the right wants to cut everything, including education? Please, do go on.


Absolutely, and no, "the right" does not want to cut everything. People with common sense and a desire for their children to be educated rather than indoctrinated want to be able to CHOOSE the school their child attends, rather than being forced into sending them to schools within their district.

quote:
Private schools are not illegal here. Socialism does not act as a replacement for capitalism, nor vice versa. Generally, they each work best alongside the other, as evidenced by all of the most prosperous periods of the U.S. and most other economically successful nations. Your assessment seems misguided.


All schools should be privatized and forced to compete, similar to how it is with colleges but to a greater degree. All federal and state educational money should be provided in the form of low-interest loans and vouchers (let's call them Ed Stamps). This will stop the bullsh1t practices such as purposely keeping grades low (or at a certain threshold) to receive the greatest level of federal/state funding. It would also force schools to compete, and so bad schools would have to close up shop while good schools thrive.

As it stands now, the government has collectively boosted spending on education by over 10x in the last few decades. Grades have not improved; but the school officials' salaries and number of staffers has certainly skyrocketed.

No sensible parent would be opposed to a voucher-based system that allows parents to "shop around" for the best school for their children. The people who oppose this are largely the unions and district officials, since they've been leeching off our current broken system for ages. They spend a lot of money lobbying to keep things just the way they are.

As for your comments about socialism and capitalism - as a matter of national policy socialism is a cancer. Capitalism works and it's what allows a country to thrive. Socialism should stay within the family, maybe your immediate local community, but by all means it should not be allowed to creep into the mainstream public on a national scale.


RE: Paper
By karimtemple on 5/23/2013 4:11:33 PM , Rating: 1
Problems often have more than one solution. You have the appearance of someone who thinks of things in "this-is-The-Answer" terms, a common symptom of ideologues and evangelicals [read: fundamentalists] -- in your case, capitalistic evangelism. "Competition" is a cure-all wonder drug to you people.

As always: What problem is this solving? Here in the real world, competition is just like most social mechanisms -- a simple tool that is appropriate for specific purposes in specific scenarios. No private school is market-viable, so your argument can only be that education should be publicly funded but not publicly accountable.

This doesn't make much sense because 1) a public group runs the way we decide it does, 2) there's no actual reason a public group can exist alongside a private market, 3) you seem to forget that there are public colleges, many of them prestigious, and 4) there are hundreds of examples of public groups that run like a top. Your camp's ideological insistence on privatization because competition is "human nature" just comes across as a weak-willed unimaginative barking.

Take the USPS for example, which for its entire history was solvent against all odds and provided an invaluable service to everyone. It simply wouldn't fail, so then lobbyists finally got clever and pushed through legislation which required the USPS to PREPAY pensions for all employees 75 years in advance:

http://en.wikipedia.org/wiki/Postal_Regulatory_Com...

Christ only knows how they managed to pull that nonsense off. Number of other entities on the planet Earth that have to do this: 0. Now all of a sudden the USPS is in "trouble," and every fundamentalist capitalist such as yourself wants to chime in about how public services don't work or something. It's irritating. Illogicality and foolishness irritate me.

tl;dr -- Push problem-solving on us, not your stupid belief system. Nobody cares. Stop preaching your ideologies and pretending your anecdotes and shallow correlations demonstrate anything, and start using study and facts in order to actually contribute something.


"Mac OS X is like living in a farmhouse in the country with no locks, and Windows is living in a house with bars on the windows in the bad part of town." -- Charlie Miller














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