Plastic Batteries Coming Soon? 200
Roland Piquepaille writes "Engineers at Brown University have built a prototype of a hybrid plastic battery that uses a conductive polymer. The system, which marries the power of a capacitor with the storage capacity of a battery, can store and deliver power efficiently. For example, during performance testing, 'it delivered more than 100 times the power of a standard alkaline battery.' Still, it's unlikely that such a device can appear on the market before several years."
summary is pretty bad, this is not a revolution (Score:5, Informative)
This is neat, but not a revolution, it's exactly the hybrid of a battery and a capacitor - it has some advantages of both.
This device has similar or less storage capacity than a battery, but can deliver its power much faster.
It has similar or less power delivery abilities than a capacitor, but twice the storage capacity.
In MANY devices, the real problem is that the batteries drain. This doesn't help that in the least bit. This will not make your electric car go farther. This only helps the situation with ultra-high-drain requirements, where a normal battery just wouldn't work.
Re:Five to ten years... (Score:5, Informative)
conducting polymer supercapacitors (Score:2, Informative)
http://www.er.uqam.ca/nobel/dep_chim/prof/belange
Other examples include:
http://scitation.aip.org/getabs/servlet/GetabsSer
Nothing new to see here, folks! Sorry!
(Yes, I am an electrochemist)
Re:summary is pretty bad, this is not a revolution (Score:4, Informative)
This has more storage than a low-storage capacitor and more power than a low-power battery.
It does not in any place, at all, say that it has more - or even as much - storage as a battery or power as a capacitor. If it had 100 times the storage of a battery it would change a lot of things.
New Standards (Score:3, Informative)
What I really want to see is "plastic" catalyst membranes in these fuelcells. That will make the cells cheap and easily replaceable, lowering the TCO consistent with the cheap fuel. It might need to be "new standard" plastic, carbon fullerenes with nanoscale features catalyzing the process. But if we can avoid the rare earth and precious metal elements fuelcells often require, we can more easily switch our power systems over to the cleaner, smaller, cheaper systems. Someday, a phone that can talk longer than I can.
Badn journalism.... (Score:3, Informative)
Re:Five to ten years... (Score:5, Informative)
P = V*I
100P = V*I
I = 100 (P/V)
For example, most powerfull easy to find rechargeable AA batteries can deliver 2.5A, or 3W, at 1.2V.
P1 = 1.2 * 2.5
P1 = 3W
This battery can power a 3W, or 2.5A, device for an hour.
With an increase of 100 times more power we have:
P2 = 100 * P1
P2 = 100 * 3
P2 = 300W
The new battery could power the 3W device for 100 hours, instead of the 1 hour that the current battery can do, or a 300W device for a single hour.
Re:Five to ten years... (Score:5, Informative)
You're confusing power with energy (which is easy to do, considering your "power bill" is actually a bill for energy used, not power). What it's saying is that its peak power delivery is 100 times that of a normal battery, so at a given voltage, it can deliver 100 times the current of a standard battery. It could well be able to store the same amount of energy, though, which means that if you're running it at its improved full power it dies in 1/100 the time of a normal battery.
Re:Five to ten years... (Score:3, Informative)
You're missing a LOT, but you'll get modded up for it anyway... The article even says it's only about 2X the capacity of current capacitors, shortly after the 100X notation.
When they say 100X more power, they mean it can deliver current 100X FASTER than a battery at a certain voltage. That actually does very slightly increase the useful life of a battery, but that's not 100X.
You are correct: (Score:3, Informative)
For example, the first cell phones were the size of a laptop, weighed a ton, and worked for about twenty minutes (did they even have a standby mode?)
fast forward to today, where cell phones are the size and weight of a multivitamin, last for hours of talking, weeks of standby, and taste like candy. (unlike the vitimin...)
Certainly reducing power requirements contributed, and that compounded the benefits from the various improvements in battery-cell technology.
Re:Five to ten years... (Score:3, Informative)
By the same token, the battery company that comes up with a product that delivers 3 times the amp-hours of similar competing battery will make a bloody fortune while all their competitors sit around undercutting each other on price trying to sell their crappy stuff to the lowest market segment.
Honestly, do you conspiracy nuts even think about what you're saying?
Re:Five to ten years... (Score:5, Informative)
You've introduced three units in your calculations:
* Power (P, in Watts W)
* Voltage (V, in Volts V)
* Current (I, in Amperes A)
However, these units only measure energy at a single point in time. But we're dealing with finite energy sources. We need to introduce another unit:
* Time (T, in Hours h, or in Seconds s)
Let's take a new look at your formula, adding a variable for time:
P * h = V * I * h
Now, let us consider a the same NiMH AA battery that you looked at earlier. To know how powerful that battery is, we need two know two things:
* Its cell voltage: 1.2V
* Its capacity rating: 2.5Ah (normally quoted in mAh / you'd see 2500mAh in the specs)
* It's maximum power drain: 2.5A
These two numbers tell us that roughly, this AA battery can deliver its quoted voltage of 1.2V for one hour if the current drain is 2.5A.
P1 = 1.2V * 2.5A * 1h
P1 = 3W * 1h = 1.2V * 2.5Ah
P1 = 3Wh = 1.2V * 2.5Ah
This battery can power a device with a power draw of 3W (equivalent to a current draw of 2.5A at a voltage of 1.2V) for one hour. It has a capacity of 3Wh (equivalent to a capacity rating of 2.5Ah at a cell voltage of 1.2V).
Let's assume that these are the specs for our new battery:
* Its cell voltage: 1.2V
* Its capacity rating: 2.5Ah
* It's maximum power drain: 250A
Now, this is where you get it wrong. What we're doing is increasing the power drain by 100, not increasing the capacity by 100.
P1 = 3W * 1h = 1.2V * 2.5A * 1h
P2 = 3W / 100 * 100 * 1h = 1.2V * 2.5A * 100 * 1h / 100
P2 = 3W * 1h = 1.2V * 250A * 0.01h
P2 = 3Wh = 1.2V * 250A * 36s
P2 = 3Wh = 1.2V * 2.5Ah
So, the new battery could power the 3W device for 1 hour, or a 300W device for 36 seconds.
Now, in reality, this new battery/capacitor hybrid is likely to have a far lower capacity rating (quoted in mAh on the box) than your typical NiMH AA cell. Also, the typical AA cell has a higher maximum power drain, which can be increased further by cooling the battery as you discharge it.
Also, in the real world, things don't work out quite as nicely as in these equations - there are power losses that vary based on a lot of factors. How fast is the battery discharged? How hot is it - and the more quickly you discharge it, the hotter it becomes, the less efficient it becomes. Is it a continuous discharge load or are we looking at spikes that give it time to cool down?
Anyway. This battery isn't quite the revolution your flawed calculations would indicate.
Good replacement for NiCd applications? (Score:4, Informative)
Re:Good replacement for NiCd applications? (Score:2, Informative)
Actually, if you look at the r/c hobby scene, LiPo batteries are the big thing these days. The voltage-per-cell is higher (3.7V per cell) than both NiMH and NiCd (1.2V per cell). But they are considerably more expensive and require special speed controllers as well as special chargers. An improperly charged/discharged LiPo battery can literally result in a fireball.