An SAE International volunteer task force working on a standard for wireless charging of electric vehicles has agreed on the frequency (85 kHz) and the power levels that should be used. “After three years of international collaboration and investigation within the team, consensus has been reached on a nominal common frequency of operation for the light-duty vehicle guideline,” said Jesse Schneider, Chair of the J2954 Task Force for Wireless Power Transfer (WPT) of Light Duty, Electric, and Plug-in Vehicles. “A common frequency of operation for WPT is essential.” Made up of OEMs, WPT suppliers, industry experts, and government representatives, the task force also nailed down the power transfer levels: the first one is identified as WPT1 and has a maximum transfer level of 3.7 kW; for WPT2 it is 7.7kW; and for WPT3 it is 22 kW. The task force plans to complete by early 2014 a Technical Information Report (TIR) on these and other “interoperability” aspects of wireless vehicle charging (e.g., coil geometries and alignment), according to Schneider, who serves as Fuel Cell, EV, Hydrogen and Standards Development Manager at BMW of North America. He said the TIR will be followed by publication of an updated J2954 standard within a year or two. For more information, or to join the task force, contact SAE’s Pat Ebejer at email@example.com.
A "stretchy" polymer developed by scientists at Stanford University and the U.S. Department of Energy's SLAC National Accelerator Laboratory in Menlo Park, CA, could open a path to self-healing electrodes in the lithium-ion batteries of future electric vehicles. The polymer coats a silicon electrode, binds it together, and spontaneously heals small cracks that develop during battery operation, the researchers said. Carbon nanoparticles are added to the polymer to conduct electricity. Silicon electrodes swell to three times their normal size when ions flow into them during charging, then return to normal size upon release of the ions in discharge. Tests found that the electrodes lasted 10 times longer when coated with the polymer, "which repaired any cracks within just a few hours," said Stanford Professor Zhenan Bao. A major challenge to overcome is the polymer's durability. Significant energy-storage capacity loss occurred after about 100 charge-discharge cycles—far fewer than 3000 typical of an electric vehicle, the researchers acknowledge. "But the promise is there," said Yi Cui, an Associate Professor at SLAC and Stanford who led the research with Bao.
Stanford postdoctoral researcher Chao Wang holds a container of self-healing polymer that can be applied to silicon electrodes to keep them from cracking and falling apart during battery operation. (Brad Plummer/SLAC)
Kia will begin selling an all-electric vehicle based on the Soul in 2014, the company announced Nov. 11. Called the Soul EV and equipped with a 27-kW·h lithium-ion battery pack, it has a target range of 120 mi (193 km) and is geared for city commuters. Front-wheel-drive prototypes currently under development are powered by an 81-kW electric motor that generates 285 N·m and delivers power to the wheels via a single-speed constant-ratio gear-reduction unit. Acceleration from 0 to 100 km/h (62 mph) will be in less than 12 s, with a top speed of about 145 km/h (90 mph). Energy recovery from braking and coasting will help recharge the battery. Plug-in charging time is expected to be up to 5 h using a standards 240-V outlet and about 25 min using fast charge with 100-kW output. Asked whether the vehicle would be equipped for SAE International J1772 fast-charging or CHAdeMO fast-charging, a Kia spokesman said the company does not want to say yet.
Panasonic Corp. will supply almost 2 billion lithium-ion battery cells to Tesla Motors over four years under an agreement announced today. The cylindrical cells (18650 form factor) will be used in the Model S and the Model X—the latter slated for production start-up by the end of 2014. The agreement builds on an earlier collaboration between the two companies to "develop next-generation automotive-grade battery cells and accelerate the market expansion of electric vehicles." The say the current cell, developed together, is a "customized technology designed specifically for optimizing electric vehicle quality and life," and offers the highest energy density in the market. Panasonic said it will increase production capacity of Li-ion cells to meet demand from Tesla.
NRG eVgo and Simon Property Group Inc. have opened what they claim is the first station in the U.S. offering ac Level 2 charging for EVs along with two different types of dc fast charging. The station is in San Diego. One of the fast-charging systems uses the SAE International J1772 combo connector (which also allows slower Level 2 charging) and the other uses the CHAdeMO system developed by TEPCO mainly for plug-in cars from Japan such as the Nissan Leaf. Under an agreement with the California Public Utilities Commission, NRG eVgo will invest about $100 million to build a network of at least 200 fast-charge-capable stations in the region stretching from San Diego to the San Joaquin Valley. As part of the agreement, the company also will build infrastructure to support Level 2 charging at a minimum of 10,000 parking spaces at multi-family, workplace, and public-facility locations in California. NRG eVgo also is building stations in Texas and the Baltimore/Washington metro area.
At the new Freedom Station in San Diego, CHAdeMo (at left) and SAE J1772 charging units stand on either side of an electronic control unit. The EV charging facility also has an ac Level 2 charger in a separate area.
Expanding on a demonstration project in Hawaii, General Motors Co. and the U.S. Army Tank Automotive Research, Development & Engineering Center (TARDEC) will again collaborate on fuel-cell technology under a new cooperative research and development agreement. The new collaboration will focus on the testing of new hydrogen fuel-cell materials and designs to evaluate their performance and durability before assembling them into full-scale fuel-cell propulsion systems. Currently, TARDEC is evaluating GM fuel-cell vehicles in a Hawaii comprehensive demonstration; the technology has possible military applications ranging from ground vehicles to mobile generators. TARDEC opened a new Fuel Cell Research Laboratory in its recently opened Ground System Power and Energy Laboratory building in Warren, MI. The state-of-the-art facility enables TARDEC to test and integrate the fuel cell systems it has been developing for military applications for more than a decade. The fuel-cell lab is located about 20 mi (32 km) from a new fuel-cell development lab that GM is building in Pontiac, MI. Physical materials and data will be shared between the facilities. Most of GM's fuel-cell work will take place there. In July, GM and Honda announced a long-term, definitive master agreement to co-develop a next-generation fuel-cell system and hydrogen storage technologies, aiming for the 2020 time frame. According to the Clean Energy Patent Growth Index, GM ranked No. 1 in total fuel-cell patents filed between 2002 and 2012.
U.S. Army Tank Automotive Research, Development & Engineering Center engineer Thiago Olson integrates a fuel cell onto a robot at TARDEC’s Fuel Cell Research Laboratory in its recently opened Ground System Power and Energy Laboratory building in Warren, MI.
Southwest Research Institute says it has deployed the first electric-vehicle aggregation system using SAE International’s J1772 standard for dc fast charging. The system, part of the Smart Power Infrastructure Demonstration for Energy Reliability and Security (SPIDERS) Phase II program, is controlling five fast-charge stations at the Fort Carson Army Base in Colorado Springs, CO. The word aggregation refers to the ability of the system to see multiple EVs as a single energy source. In August, the system passed integration and acceptance testing, successfully aggregating electric vehicles from two vehicle manufacturers equipped with SAE-compliant bidirectional charging interfaces. “The SwRI aggregation system manages a fleet of electric vehicles, controlling both vehicle charging and microgrid needs and supporting vehicle schedules, as well as supplementing the base’s energy supply,” said Sean Mitchem, project manager and a principal analyst in SwRI’s Automation and Data Systems Division. Batteries in the EVs serve as cushion against fluctuations in the grid, creating more stability and resiliency while improving the grid’s ability to accommodate renewable energy from a solar energy array at the base. “Using this new technology, electric vehicles can use or store this green energy more efficiently than previously was possible,” Mitchem said.
Boulder Electric Vehicle is one of the companies supplying EVs for the V2G project at Fort Carson Army Base in Colorado.
The U.S. Department of Energy recently opened what it describes as a "one-of-a-kind national secure data center" at its National Renewable Energy Laboratory (NREL) in Golden, CO. The National Fuel Cell Technology Evaluation Center (NFCTEC) allows industry, academia, and government organizations to submit and review data gathered from projects to advance cost-effective fuel-cell technology. NFCTEC will also help accelerate the commercialization of fuel-cell technologies by strengthening data collection from fuel-cell systems and components operating under real-world conditions, and analysis of these detailed data that can be compared to technical targets. The NFCTEC is housed within an area of the Energy Systems Integration Facility at NREL, and is specifically designed for the secure management, storage, and processing of proprietary data from industry and other stakeholders. Aggregated analysis results that show the status and progress of the technology, but do not identify individual companies, are available to the public. With support from the DoE, NREL has been performing independent, third-party analysis and validation of proprietary hydrogen and fuel-cell technologies in real-world operation since 2004. To date, NREL has collected and analyzed more than 2 million h of operational data involving the use of more than 450,000 kg (1 million lb) of hydrogen.
A Toyota Highlander FCV fills up at the renewable hydrogen fueling station at National Renewable Energy Laboratory facilities in Colorado.
Robert Bosch GmbH is leading a new €4.3 million German research project to use the power circuitry in a lithium-ion battery for the secondary purpose of transmitting data about the health of the individual cells. Dual use of the battery's power circuit would eliminate the need for costly extra data-transmission wiring that has been necessary in Li-ion battery systems used to date, according to Bosch. Germany's Federal Ministry of Education and Research will provide €2.5 million in funding through May 2016 for the project called IntLiIon (Intelligent data bus concepts for Lithium-Ion batteries in electric and hybrid vehicles). Other participants are Pro Design Electronic GmbH, the University of Applied Sciences and Arts Hannover, and the Karlsruhe Institute of Technology. Funding from the Ministry of Education and Research comes as part of the “Energy-efficient and safe electromobility” initiative (STROM 2) within the German federal government's “ICT 2020 - Research for Innovation” program.
Scientists at the U.S. Department of Energy's Oak Ridge National Laboratory have developed a new oxygen "sponge" that can easily absorb or shed oxygen atoms at low temperatures. Materials with these novel characteristics would be useful in devices such as rechargeable batteries, sensors, gas converters, and fuel cells. Materials containing atoms that can switch back and forth between multiple oxidation states are technologically important but very rare in nature, said ORNL's Ho Nyung Lee, who led the international research team. "Typically, most elements have a stable oxidation state, and they want to stay there," he said. "So far, there aren't many known materials in which atoms are easily convertible between different valence states. We've found a chemical substance that can reversibly change between phases at rather low temperatures without deteriorating, which is a very intriguing phenomenon." Many energy-storage and sensor devices rely on this valence-switching trick, known as a reduction-oxidation, or "redox" reaction. For instance, catalytic gas converters use platinum-based metals to transform harmful emissions such as carbon monoxide into nontoxic gases by adding oxygen. Less expensive oxide-based alternatives to platinum usually require very high temperatures—at least 600 to 700°C—to trigger the redox reactions, making such materials impractical in conventional applications. "We show that our multivalent oxygen sponges can undergo such a redox process at as low as 200°C, which is comparable to the working temperature of noble metal catalysts," Lee said. The team's material consists of strontium cobaltite, which is known to occur in a preferred crystalline form called brownmillerite. Through an epitaxial stabilization process, the ORNL-led team discovered a new recipe to synthesize the material in a more desirable phase known as perovskite.