Of all the criticisms of electric vehicles, probably the most commonly-heard is that their batteries take too long to recharge – after all, limited range wouldn't be such a big deal if the cars could be juiced up while out and about, in just a few minutes. Well, while no one is promising anything, new batteries developed at the University of Illinois, Urbana-Champaign do indeed look like they might be a step very much in the right direction. They are said to offer all the advantages of capacitors and batteries, in one unit.
"This system that we have gives you capacitor-like power with battery-like energy," said U Illinois' Paul Braun, a professor of materials science and engineering. "Most capacitors store very little energy. They can release it very fast, but they can't hold much. Most batteries store a reasonably large amount of energy, but they can't provide or receive energy rapidly. This does both."
The speed at which conventional batteries are able to charge or discharge can be dramatically increased by changing the form of their active material into a thin film, but such films have typically lacked the volume to be able to store a significant amount of energy. In the case of Braun's batteries, however, that thin film has been formed into a three-dimensional structure, thus increasing its storage capacity.
Batteries equipped with the 3D film have been demonstrated to work normally in electrical devices, while being able to charge and discharge 10 to 100 times faster than their conventional counterparts.
To make the three-dimensional thin film, the researchers coated a surface with nanoscale spheres, which self-assembled into a lattice-like arrangement. The spaces between and around the spheres were then coated with metal, after which the spheres were melted or dissolved away, leaving the metal as a framework of empty pores. Electropolishing was then used to enlarge the pores and open up the framework, after which it was coated with a layer of the active material – both lithium-ion and nickel metal hydride batteries were created.
The system utilizes processes already used on a large scale, so it would reportedly be easy to scale up. It could also be used with any type of battery, not just Li-ion and NiMH.
The implications for electric vehicles are particularly exciting. "If you had the ability to charge rapidly, instead of taking hours to charge the vehicle you could potentially have vehicles that would charge in similar times as needed to refuel a car with gasoline," Braun said. "If you had five-minute charge capability, you would think of this the same way you do an internal combustion engine. You would just pull up to a charging station and fill up."
Braun and his team believe that the technology could be used not only for making electric cars more viable, but also for allowing phones or laptops to be able to recharge in seconds or minutes. It could also result in high-power lasers or defibrillators that don't need to warm up before or between pulses.
I think wireless (magnetic field) charging has potential - municipalities placing generating \"pads\" at traffic signals and public parking spots where the consumer is identified (by the vehicle\'s tag or RFID) and the power that\'s delivered is metered and billed accordingly.
Also, this tech (increased energy capacity) will greatly enhance the regen-braking aspect of electric vehicles, as their battery pack\'s currently limited ability in this area is a primary hindrance.
WHAT \"PHYSICAL LIMITATIONS\"?
The CHAdeMO fast charge method allows 125 Amps at 500 VDC ... that\'s 62.5 kW ... the Chevy Volt would charge (from empty ie. 10 kWhr) in about 9 minutes (if GM supported CHAdeMO).
ABB has developed DC fast charging stations that can deliver 125A, 250A or 500A DC current for charging, compatible with CHAdeMO protocols, or up to 250 kW. The Nissan Leaf would charge (from empty ie. 34 kWhr) in about 8 minutes.
With proper engineering, (safe) connectors and cables could handle 1,000 Amps at 1,000 VDC ... that\'s 1,000 kW or 1 MegaWatt. The Tesla Roadster would charge (from empty ie. 52 kWhr) in about 3 minutes.
The \"Grid\" needs to be \"buffered\" with banks of batteries that charge overnight. EVoasis.com EVSTAT Charging Stations have underground battery banks that handle multiple vehicles for fast charging.
http://www.youtube.com/watch?v=4V-D8p3eLuA at around 0:40 sec for the statement
http://www.proterra.com/index.php
Can you imagine the power capacity of the charging station that can dump the amount of electricity into a battery? The average 120 volt plug can supply a maximum of 1,500 watts (or 1.5kw/hr) it takes about 12 hours for a full charge, so that\'s 12 X 1.5KW or 18 thousand watts...compress this into 5 minutes that\'s 216 thousand watts of power that will need to flow from the charging station into your batteries! I don\'t know about you, but I would not want to stand anywhere other than an armored bunker while that thing charges! It\'s like in the movie Demolition Man where where Wesley Snipes sticks the shock rod into the charging port of a police car....BOOM!
Take that one step further do it on main arterial roads charge while driving
The problem I see with these batteries is that their overall lifespan is probably not improved over traditional batteries, because they will have the same problems of surface build-up and holes that cause normal batteries to dramatically reduce in effectiveness in a few years.
Super/ultra capacitors would be a great solution for this if they didn\'t tend to be tolerant of only low voltages. I still think that we will have to move more toward capacitive solutions than battery solutions to see real long term improvement in EV power.
To really support widespread distribution and use of such stations to the majority of the US populous, the energy grid would have to not only be massively retrofitted, but also supplied by the only reasonable energy source for such an endeavor: nuclear energy.
Unfortunately, that path is most likely dead due to political cowardice. Though, I don\'t think I\'d put any in California...