They do use the nickel batteries in electric vehicles: great article. this sur eseems like a no brainer to me---got nickel stocks-grin?? electric vehicle manufactures cannot keep up with demand.
THE MAGAZINE DEVOTED TO NICKEL AND ITS APPLICATIONS
March 2004
Volume 19, Number 2
THE HONDA INSIGHT is one of three commercially-available hybrid electric vehicles on the roads today. The other two are the Honda Civic and Toyota Prius.
NICKEL METAL HYDRIDE (NiMH) batteries play a key role in powering hydbrid electric vehicles.
THE LATEST DESIGN OF NiMH battery modules use the prismatic construction shown here. This facilitates the release of heat and makes installation easier than it was for previous designs.
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NiMH Batteries Tops in Hybrids
Nickel batteries play a key role in powering sustainable transport alternatives. By Barry Waters
Nickel magazine, March, 2004 -- Technological development has reduced the size, weight and cost of the nickel metal hydride (NiMH) battery packs used in hybrid electric vehicles (HEVs). Relatively compact in size, they now have sufficient power, reliability and life expectancy to have been selected for the majority of mass-produced HEVs, such as the Honda Insight and Toyota Prius.
Further improvements will increase the number of HEVs from the hundreds of thousands that are now on the road to millions in the future. The NiMH battery has made possible a large reduction in vehicle pollutants, while improving the utilization of scarce energy resources. In the future, when renewable energy is used to generate hydrogen for fuel cell vehicles, a hybrid design using NiMH batteries will be key to achieving efficient energy usage and to powering sustainable transportation.
These are some of the conclusions presented at the 20th International Electric Vehicle Symposium and Exposition, or EVS20, held in Long Beach, California, U.S.A., in November 2003. The event is the premier international event for the electric drive industry, and the theme of the 2003 symposium was "powering sustainable transportation." EVS20 featured exhibits by more than 100 international electric drive businesses, the display of 60 battery, hybrid and fuel cell vehicles available for testing, and presentations by more than 200 of the world's leading authorities on business, technical and policy issues.
The technologies that may ultimately drive the conversion from the internal combustion engine to electric drive systems were reviewed comprehensively. In addition to reduced vehicle emissions, such technologies open up the possibility for greatly improved fuel efficiency and, ultimately, the use of hydrogen fuels.
One of the yardsticks used to assess the environmental cost of a technology is the "well to wheel" efficiency. This expresses the overall efficiency of an energy source, from extraction from the earth to when it turns the wheels of a vehicle. A modern, conventional automobile has an overall efficiency of only 14%, according to Toyota. The first-generation Prius hybrid HEV attains 28%, and the second-generation 2004 model, 32%. This compares with the target efficiency for Toyota's fuel cell hybrid vehicle prototype of 42% (assuming hydrogen fuel is derived from compressed natural gas).
All these vehicles increase their efficiencies by recapturing energy lost to friction through conventional braking, that is, by a process called "regenerative braking." And while there are various alternative ways to capture this energy, Honda and Toyota, the only suppliers of mass-produced HEVs on the market, have chosen NiMH secondary batteries.
NiMH batteries use nickel-oxyhydroxide doped with various proprietary elements as the positive electrode. The electrolyte is normally aqueous potassium hydroxide. The negative electrode is a nickel alloy containing lanthanum or certain transition metals, including vanadium, titanium and zirconium. Hydrogen is absorbed at this negative electrode to form the nickel metal hydride and generate electricity.
Papers presented by Panasonic and Toyota at the symposium detailed advances in the latest generation of NiMH batteries. The prismatic module construction of the new battery allows superior heat-releasing performance and ease of installation. Used for the 2004 Toyota Prius, this battery, at 30 kilograms, is 25% lighter than its predecessor. It is warranted for eight years, but the expectation is that it can last 15 years.
NiMH batteries also powered an all-electric vehicle fleet that was tested by Southern California Edison. Five test vehicles out of the 320-vehicle fleet were selected for detailed testing, and the conclusion was that a 210,000-to-240,000-kilometre NiMH life could be expected. In five years, the fleet of 320 electric vehicles logged more than 110 million kilometres, eliminating about 915 tonnes of air pollutants and preventing more than 4,100 tonnes of tailpipe emissions.
Barry Waters is Director, Nickel Use Support and Development Group, Nickel Institute.
PHOTOS: Toyota and Honda
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Web site: www.evs20.org
References:
1. A Guide to Hybrid Synergy Drive, Toyota Motor Corporation
2. Development of Prismatic Type Nickel/Metal-Hydride Battery for HEV, K. Ito & M. Ohnishi, Proceedings, EVS-20, The 20th International Electric Vehicle Symposium and Exposition, 2003
3. Development of a New Battery System for Hybrid Vehicles, S. Nagata, H. Umeyama, Y. Kikuchi & H. Yamashita, ibid.
4. 100,000 Mile Evaluation of the Toyota RAV4 EV, T.J. Knipe, L. Gaillac & J. Argueta, ibid.
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