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Knightrous
Site Admin
Joined: 15 Jun 2004
Posts: 8511
Location: NSW
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Hybrid Motor Vehicles & Ultracapacitors.
Just been skimming through wired.com and found this interesting article :http://www.wired.com/news/autotech/0,2554,69519,00.html
quote:
Hacking the Hybrid Vehicle
Page 1 of 1
By John Gartner
02:00 AM Nov. 16, 2005 PT
Engineers are developing adapter kits for hybrid vehicles that will increase their efficiency to 100 miles per gallon by powering them solely on electricity during short trips.
Today's hybrid vehicles use electricity stored in batteries to assist the gasoline engine in acceleration and to completely power the vehicle while idling or at steady low speeds (generally less than 25 mph). Vehicles such as the Toyota Prius, Honda Civic Hybrid and Ford Escape Hybrid include drive-train management systems that automatically decide when to use the batteries or internal-combustion engine.
Enter CalCars and EDrive, organizations developing modification kits that enable the Toyota Prius to be recharged from the grid. And a new group of automotive component suppliers, the Advanced Hybrid Vehicle Development Consortium, hopes to develop technology that enables hybrids to run without help from the gasoline engine for up to 50 miles.
Referring to "plug-in" hybrids, David West, vice president of marketing for consortium co-founder Raser Technologies, said that "80 percent of cars would be able to drive five days per week without using their combustion engines." West said consumers would save money since the equivalent of one gallon of gasoline costs just 60 cents in electric power.
Consumers have rejected plug-in alternative vehicles in the past. But with gas prices hitting record highs, members of the consortium believe the timing is right to try again with new and improved technology.
The consortium will develop a prototype hybrid vehicle within a year that includes more-powerful electric motors, longer-lasting batteries and ultracapacitors that can store electricity used for acceleration, West said. The prototype will cost about as much to build as today's hybrids, because some components such as the flywheel will be eliminated. Not only will the vehicle get more than 100 mpg, but consumers will save even more by tapping into the grid.
The group hopes to license the hybrid technology to auto companies that have yet to produce hybrids, which would "enable other automakers to jump in the game without having to do 15 years of (research and development)," West said. Other companies participating in the group include lithium-ion battery manufacturers Electrovaya and Enax, utility Pacific Gas and Electric and Maxwell Technologies, a company that wants to introduce its ultracapacitor technology into hybrid vehicles.
Richard Smith, Maxwell's executive vice president, said ultracapacitors -- which store energy by separating negative and positive charges along plates -- should eventually be included in all hybrids because they are 10 times more powerful than batteries at providing the bursts of energy needed to accelerate a vehicle. Ultracapacitors are 98 percent efficient when receiving energy from the regenerative braking systems used in hybrids, while batteries are 60 just percent efficient, according to Smith.
But ultracapacitors aren't nearly as efficient at storing energy, so cars traveling more than a few miles will need batteries as well, Smith said. Ultracapacitors haven't been practical until recent improvements were made in the technology.
Earlier this year, BMW introduced the X3 EfficientDynamics concept car, and students at Brigham Young University developed an electric drag racer, both powered by ultracapacitors.
Perry Carter, an associate professor at BYU who worked with students on the vehicle, said ultracapacitor technology is promising but not yet practical -- the drag racer used $22,000 worth of ultracapacitors for a 14-second run on a track.
The original Toyota Prius concept car included ultracapacitors, according Dave Hermance, Toyota's executive engineer for advanced technology vehicles, but they didn't make it into the production vehicle because of their cost and size. But those were previous-generation technologies, and Smith said the price of new ultracapacitors is now on par with batteries.
Hermance is still not convinced. In general, he said, ultracapacitors are better suited to large vehicles like trucks or buses that stop and start frequently, because their heavy loads generate a lot of energy when braking.
Plug-in hybrids "are not viable with today's battery technology," Hermance said. He said the Prius' power-management system keeps the batteries charged at 60 percent, plus or minus 15 percent to extend their life. Running solely on electricity would discharge the batteries beyond their optimal range and burn them out after approximately 2,500 cycles, or about six years of use, he said.
Selling plug-in hybrids will also cause confusion with consumers and could hurt sales, Hermance said. Most people don't want the responsibility of recharging batteries every day. Plus, he said, manufacturers spent years convincing consumers that hybrids were not like the electric vehicles that failed to gain commercial acceptance.
But Raser Technologies' West said powering a vehicle with electricity will cost about a quarter the price of using gasoline, which he believes offsets any inconvenience from having to charge the vehicle overnight.
Ultracap's sound pretty interesting to me for those people wanting large sudden bursts for bots, maybe the use of NiMH's packs with some Ultracaps on weapon motors. Will definately google search this subject further _________________ https://www.halfdonethings.com/
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Sat Nov 19, 2005 6:13 am |
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ffej
Experienced Roboteer
Joined: 22 Jun 2004
Posts: 595
Location: Kurrajong, NSW
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Cant wait till the next gen lithium batteries get out of the prototype stage, will pretty much eliminate the need for ICE based cars, very large capacity, high discharge, very long (~10000 cycles) lifetime and best of all, 5 minutes to 90% charge . . . mmmmm *drool* They work out lighter than a comparable fuel cell / electric motor combo, so they will really kick the crap out of that technology, which I always thought was a huge gimmic (hydrogen is an energy vector, not a source, there will always be a great amount of inefficiency converting 2H2O to 2H2 O2. . . . hydrogen economy, pfft)
Heres a prototype Subaru is working on . . .
http://www.treehugger.com/files/2005/08/subaru_joins_ra.php
Its based on a Japanese model ICE, the R1 K-car, which is why it looks weird as K-cars are required to fit into limiting dimensions. The prototype can do 75 miles on a charge, and they hope to have it doing 120 miles on a charge at time of release. . . the amazing part is that the batteries are about the size of a VCR, weigh just 15~20kg and of course charge to 90% in 5 minutes.
However, I still believe there going about it all wrong, and missing out on a huge advantage of the electric car . . . modularity. Get rid of that whole engine in one end business, run brushless wheel motors, and stick the batteries whereever is easiest, they dont need to be in one clump. This would lead to much lower cost, more reliablem lighter and efficent (no gearbox, diff, drive shaft CV joints etc . . . hell, no brakes either if they wanted to go all out) and more original looking cars with lower, aerodynamic profiles. _________________ Jeff Ferrara
fb@ffej.net
ffej.net
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Wed Mar 08, 2006 11:37 pm |
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Grotto
Joined: 30 Aug 2005
Posts: 38
Location: Morisset NSW
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Very true, but everyone (mostly ) knows petrol burns easily,
and car designers & petrol stations have spent decades finding
better (but not perfect) safeguards.
Lithium batteries are still 'new' so long-term studies have yet to
take place, so safeguards will be few to start with. And if you
are going to leave the car alone in the garage while it is
charging, its got a chance to get bad before you notice.
I have torched a lithium mobile-phone battery pack as a test
just to see for myself. (sorry, no pics- no camera)
I did this by fully carging it, possibly a bit over charged,
and dead shorting it with a large nail. Easy, too easy?
I would rather a pertrol fire myself, lithium burns HOT,
we are talking melting steel heat.
Please EVERYONE bear in mind, Im and NOT saying to avoid
lithium, just be aware of potential dangers, thats all.
Love the video Prong, but you get that when you use petrol
to cool down a hot exhaust pipe. Works with mowers too,
I had to wear a beanie for 3 weeks! _________________ "The future is not set. There is no fate but what WE make."
........CEO Cyberdyne Systems
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Mon Aug 21, 2006 10:00 am |
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