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Proton Polymer Battery
Reality Master 101 writes: "Saw this originally in Pop Science, but check out NEC's press release. More like a capacitor than a battery, it can be recharged in 5 minutes and has a life of 10s of thousands of cycles. NEC claims it has the highest energy density of any electrochemical device, as well as a current discharge rate 20 times higher than lead batteries (20mAh device: 9A in 10 seconds... electric cars, anyone?). To top it off, they can make it in a credit card-thin format. Very cool, and about time!"
After reading the various replies in this thread, I couldn't resist...
By looking at the page of NEC it seems to suggest that their 'cell' is 12V/20mAh, with a connected version of 10 cells for 12V 200mAh. The 200mAh model is about as thick as three or four floppy disks and about 2/3 the height.
The average laptop-battery is about 1 1/2 the height(length) of a floppy and about 5 floppies think. (well, mine is). My current battery provides me with about 3.5 hours of juice and it provides 3600mAh at 10.8V. (Lithium/Ion)
Now there's always the difficulty in expressing these things because almost all variables are related. I'll try to calculate the batteries back to their energy-values in Joules.
3600mAh at 10.8V provides (3.6A * 10.8V * 3600 seconds)== 139968 Joules of power.
For the sake of argument, let's compensate the 'thinness' of the battery (compared with my current battery) by assuming three fit in the length of the 'current' battery.
That would provide 600mAh at 12V in a similar battery. This mounts to (0.6A * 12V * 3600s) 25920 Joules. Even in a very positive estimate of 5 200mAh cells in the same size, it would provide only (1A * 12V * 3600s) 43200 Joules of power. (this last figure is slightly under 1/3 of the amount of power my current battery provides)
As a conclusion, the new battery from NEC won't give us the "durability" most of you have been celebrating about. However, as NEC's article states, it has a significantly higher discharge rate. This 'battery' therefore sooner approaches (as some posters already stated) the specifications of 'burst' capacitors.
Then again, it has the potential for improvement. As Ericsson is already working with Lithium/Polymer (i.e. Electron/Polymer, as opposed to NEC's Proton/Polymer) batteries in their cell-phones, we should be seeing credit-card thickness batteries with longer lifespans for (to begin with) PDA's/cellphones pretty soon.
Another thing I noticed in the posts is a discussion about the units of measurement. Things like the 'Coulomb' and the 'KWh'.
Basically, energy is expressed by Joules. And Power is expressed in Watts, which equals 1 Joule 'consumed' in 1 second. Electrical power (consumption) is calculated by the formula of Power(consumption) equals Voltage times Current (or P=V*I).
[Start inflammatory bit]
Up until now, this has all been highschool-level physics. Which means either one of three things:
1) The posters didn't read the article, clicked on reply and started yapping away,
2) The posters haven't finished highschool yet.
3) The posters won't finish highschool.
[End inflammatory bit]
So the timespan, potential and current are interconnected. Enter the Coulomb. Coulomb is a measurement of charge. Current can therefore be expressed in Coulombs as well as Amps.
1 Coulomb/sec equals 1 Ampere. 1 Ampere equals 1 Watt over 1 Volt. Which in turn means 1 Joule over 1 Volt in 1 second.
(1sec * 1J) * 1V == Watts * Potential == Current
1sec * (1J * 1V) == Time * Coulombs == Current
[Thus Coulomb is the relation between energetic value and potential difference]
The KWh is merely a 'compound' unit for use by power-companies who don't want to daunt their customers by stating a 9-figure number on the bill as the 'power consumed'. Besides, the cost/Watt consumed are so small, they can't reasonably calculate with it.
So, the KWh is one KW (1000 Watts), sustained for one hour (3600 seconds), which results in 3.6 million watts. Stating "200KWh consumed" looks so much friendlier than saying "720000000 Watts consumed" (720 _million_ watts).
Running 4 computers 24/7 in your home (which I do), without the monitors and having saved on the number of harddisks, would probably end up around 300Watts continously. 300 Watts * 3600 * 24 equals 25920000 Watts per day, or 7.2 KWh.
This, at 365 days a year, ends up in a whopping 2628 KWh on computer power-consumption a year alone.
Here is a more recent article (August 2000), so it appears to be truthful. It includes more correct info pertaining to power vs. energy density as well.
After an exhaustive "9 volt to the tongue" type experiment outside NEC's cafeteria, 98% of the random subjects all reported that the "damn proton battery hurts like a motherfucker." The remaining 2% had tongue piercings and could not legally participate in the in-company experiment.
Results will be expected on-line shortly at the NEC homepage, with Realmedia clips of the after-effects of licking including slurred incomprehensible speech that may or may not be profanity.
An NEC engineer was later quoted as saying, "we're working hard on clear and concise warning labels for kids so they don't do the same thing, but it probably won't make much of a difference," probably refering to socially inept and possibly really stupid children like his own son, Samuel, who is often the subject of taunts and dares.
At last, a UPS that won't outweigh its own volume in neutron star matter...
End of lesson. You may press the button.
The power density is high for this material, NOT the ENERGY DENSITY. Power density is a measurement of high-current discharge per unit of time per unit of volume(or weight).
The power density for these devices is in excess of 1,000 Watts/Kg, much higher than the few hundred for lead acids/NiCd's etc. Although--- the energy density of the NEC proton batteries is still rather dissapointing at 10-15 WattHours/Kg compared to the 20-30 WattHours/Kg of lead-acids'. But since it's such a new technology IMHO there is much prospect for improvment in this area, and getting competitive(in terms of batteries) energy densities out of these things is only a matter of time.
There is an article in the "Nikkei BP AsiaBizTech" site here: http://www.nikkeib p.a siabiztech.com/nea/200008/cmpo_108677.html
- "Hear that?! The percolations are imminent! Cease your ingress!"