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Battery electric vehicles or '''BEV'''s are Electric Vehicle s whose main energy storage is in the chemical energy of Batteries . BEVs are the most common form of what is defined by the California Air Resources Board ( CARB ) as Zero Emission (ZEV) passenger Automobile s, because they produce no emissions while being driven. The Electrical Energy carried onboard a BEV to power the motors is obtained from a variety of Battery chemistries arranged into Battery Pack s. For additional range Genset Trailer s or Pusher Trailer s are sometimes used, forming a type of Hybrid Vehicle . Batteries used in electric vehicles include "flooded" Lead-acid , Absorbed Glass Mat , NiCd , Nickel Metal Hydride , Li-ion , Li-poly and Zinc-air Batteries . While Hybrid Vehicle s apply many of the technical advances first developed for BEVs, they are not considered BEVs. Of interest to BEV developers, however, is the fact that hybrid vehicles are advancing the state of the art (in cost/performance ratios) of batteries, electric motors, chargers, and motor controllers, which may bode well for the future of both pure electric vehicles and the so called "plug-in hybrid". in production electric car capable of reaching 0-100km/h in 4.5 seconds]] HISTORY See Also: History of the electric vehicle BEVs were among the earliest automobiles, and before the preeminence of light, powerful Internal Combustion Engines , electric automobiles held many vehicle land speed and distance records in the early 1900s. Most notable was perhaps breaking of the 105.88 km/h (65.79 mph) speed barrier by Camille Jenatzy on April 29 , 1899 in his rocket-like EV named ''La Jamais Contente''. This was the first world record over 100 km/h. BEVs were produced by Anthony Electric , Baker Electric , Detroit Electric , and others and at one point in history out-sold gasoline-powered vehicles. Some feel that the introduction of the to replenish their water supply. The truth may be that EV's had fallen out of favor over the mass produced Ford Model-T which went into production four years earlier in 1908 . {Link without Title} EFFICIENCY Production and is equivalent to 1.46 kWh/mi and the 70 mpg Insight gets 0.48 kWh/mi (assuming 33.6 kWh per U.S. gallon of gasoline), so battery electric cars vehicles are relatively efficient. When comparisons are made for the total energy cycle, the efficiency figures for BEVs drop, but such calculations are ''not'' commonly offered for ICE vehicles (e.g. the loss of efficiency from energy used to produce specialized fuels such as gasoline as compared to the raw energy available from Crude Oil or Natural Gas . CO2 emission comparisons {Link without Title} are one good indication of the current grid-mix vs gasoline consumption. Such comparisons include production, transmission, charging, and vehicle losses. The CO2 emissions can improve for BEVs through the use of sustainable grid or local resources but are essentially fixed for gasoline vehicles. Unfortunately the EV1 , Ranger EV , EVPlus, and other production vehicles are missing from this site.
It is important to study the full effect of any vehicle design, especially when promoted as better than the status quo. The goal may be to look at overall efficiency only or it may be the total environmental impact, since environmental damage reduction is often the goal behind alternative vehicle efforts. Many factors must be considered when making an overall comparison of total environmental impact. The most comprehensive comparison is known as a cradle-to-grave or lifecycle analysis. The analysis considers all inputs including original production and fuel sources and all outputs and end products including emissions and disposal. The varying amounts and types of outputs and inputs vary in their environmental effects and are difficult to directly compare. For example, are the environmental effects of Nickel or Cadmium Contamination from a battery production facility less than those of Hydrocarbon Emission s or from Petroleum Refining ? If so, how much, or how much of each would be equivalent? Similar types of questions would need to be resolved for each input and output in order to make a comparison. A large lifecycle input difference is that the electric vehicle requires electricity instead of a liquid fuel. The advantage of the electric vehicle is that the electricity can be provided by Renewable Energy . However, if the electricity is produced from Fossil Fuel sources (as most electricity currently is) the advantage of the electric vehicle is reduced, or nearly eliminated. {Link without Title} Thus utilizing and developing additional renewable energy sources is required for electric vehicles to further reduce their net emissions. The input for electric vehicle production that differs from internal combustion types is primarily in the large battery. The batteries, however, may not last as long as combustion engines, and needing to be replaced would account for a greater input requirement for their production. However, as BEVs do not require an ICE engine, support systems or related maintenance, they should be more reliable and require less maintenance. Although BEVs are not common, there are related markets which require advances in battery technology, such as mobile phones, laptops, forklifts and hybrid electric vehicles. Improvements to battery technology for any of these other markets will make BEVs more practical too. Aerodynamic drag has a big impact on efficiency as the speed of the vehicle increases. A list of cars and their corresponding Drag Coefficient s is listed Here . PERFORMANCE Many of today's electric vehicles are capable of acceleration performance which exceeds that of conventional gasoline powered vehicles. Electric vehicles can utilize a direct motor to wheel configuration which increases the power deliverability to the wheels. Having multiple motors connected directly to the wheels allows for each of the wheels to be used for both propulsion and as braking systems, thereby increasing traction. In some cases, the motor can be housed directly in the wheel, such as in the Whispering Wheel design, which lowers the center of gravity and reduces the number of moving parts. When not fitted with an axle, differential or transmission, many electric vehicles have greater torque availability, which goes directly to accelerating the wheels. A single gear design in some electric vehicles eliminates gear shifting, giving the newer electric vehicles both smoother acceleration and braking. This also allows higher torque at wide rpm levels. Nonetheless, top speed and total possible drivetrain efficiency are severely limited by the lack of a gearbox. For example, the Venturi Fetish delivers Supercar acceleration, yet is limited to a top speed of only 100 mph. FUELS There are no currently available technologies which can provide all of the energy required for the life of a BEV car. This means that all BEV cars must be refuelled by periodic charging of the batteries. BEVs most commonly charge from the Power Grid , which is in turn generated from a variety of domestic resources — primarily coal, natural gas, and nuclear. Home power such as roof top photovoltaic panels, microhydro or wind can also be used. Electricity can also be supplied with traditional fuels via a generator. RANGE The range of a BEV depends greatly on the number and type of batteries used. The weight and type of vehicle also has an impact just as it does on the mileage of traditional vehicles. Conversions usually use lead-acid batteries because they are the most available and inexpensive, such conversions generally have 20 to 50 miles (30 to 80 km) of range and are built to satisfy the drivers' individual needs. Production EVs with lead-acid batteries are capable of up to 80 miles (130 km) per charge. NiMH chemistries have high energy density and can deliver up to 120 miles (200 km) of range. Lithium ion equipped EVs have been claimed in s or Genset Trailer s in order to function as a Hybrid Vehicle for occasions when unlimited range is desired without the additional weight during normal short range use. The vehicle becomes an internal combustion vehicle when utilizing the trailer, but it allows the greater range that may be needed for limited times while making the advantages of the BEV available for most shorter trips. In practice most vehicle journeys of all kinds are quite short, the majority being under 30 km (20 mi) per day. Thus, a BEV that can do 60 km (40 mi) in a day is quite practical for most trips for most users, and a substantial additional range can be added for commuters where charging facilities are available at the destination. BATTERY CHARGING The charging time is limited primarily by the capacity of the grid connection. A normal household outlet is between 1.5 kW in the US to 3 kW in countries with 240 V supply. The main connection to a house might be able to sustain 10 kW, and special wiring can be installed to use this. At this higher power level charging even a small, 7 kWh (14–28 mi) pack, would probably require one hour. Compare this to the effective power delivery rate of an average petrol pump, about 5,000 kW. Even if the supply power can be increased, most batteries do not accept charge at greater than their 'charge rate' C1.
Most people do not require fast recharging because they have enough time (6 to 8 hours) during the work day or overnight to refuel. As the charging does not require attention it takes a few seconds for an owner to plug in and unplug their vehicle. Many BEV drivers prefer refueling at home, avoiding the inconvenience of visiting a petrol station. Some workplaces provide special parking bays for electric vehicles with charging equipment provided. The charging power can be connected to the car in two ways. The first is a direct electrical connection known as conductive coupling. This might be as simple as a mains lead into a weather proof socket through to special high capacity cables with connectors to protect the user from high voltages. The second approach is known as inductive coupling. A special 'paddle' is inserted into a slot on the car. The paddle is one winding of a transformer, while the other is built into the car. When the paddle is inserted it completes a magnetic circuit which provides power to the battery pack. The major advantage of this approach is that there is no possibility of electrocution as there are no exposed conductors although interlocks can make conductive coupling nearly as safe. Conductive coupling equipment is lower in cost and much more efficient due to a vastly lower component count. BATTERY LIFE Individual batteries are usually arranged into large Battery Pack s of various Voltage and Ampere-hour capacity products to give the required energy capacities. Battery life must be considered when calculating cost of operation, as all batteries wear out and must be replaced. The rate at which they expire depends on a number of factors. New scientific and empirical evidence from running individual EV conversions shows that most of these negative factors linked to batteries connected in series for traction application can be mitigated with good DC/DC based Battery Management System , thermo insulation/venting, and proper care. That also includes selecting a well balanced mix of compontents oriented towards specific performance properties, i.e. range, speed. For instance a recombination type of lead-acid battery with C1 hour discharge rate about 120Ah (equals to 220Ah C20 "marketing rating") should be used accordingly. Therefore the EV overall consumption of particular low/mid voltage vehicle should not often exceseed in this example 80-100% of this C1 hours rating — this applies for more advanced battery chemistries like Li-ion with slightly higher discharges C3-C5 as well. In this particular example, longevity of the lead-acid battery pack will be preserved by not discharging it in a prolonged or continuous regime above 120Ah currents. The depth of discharge (DOD) is the recommended proportion of the total available energy storage for which that battery will achieve its rated cycles. Deep cycle lead-acid batteries generally should not be discharged below 50% capacity. More modern formulations can survive deeper cycles. In real world use some fleet RAV4-EVs have exceeded 100,000 miles (160,000 km) with little degradation in their daily range {Link without Title} . Jay Leno 's 1912? Baker Electric still operates on its original Edison Cells . Battery replacement costs may be partially or fully offset by the lack of regular maintenance such as oil and filter changes and by greater reliability due to fewer moving parts. Critics claim that batteries pose a serious environmental hazard requiring significant disposal or recycling costs. Some of the chemicals used in the manufacture of advanced batteries such as Li-ion , Li Ion Polymer and Zinc-air are hazardous and potentially environmentally damaging. While these technologies are developed for small markets this is not a concern, but if production was to be scaled to match current car demand the risks might become unacceptable. Supporters counter with the fact that traditional car batteries are one of the most successful Recycling programs and that widespread use of battery electric vehicles would require the implementation of similar recycling regulations. More modern formulations also tend to use lighter, more biologically remediable elements such as iron, lithium, carbon and zinc. In particular, moving away from the heavy metals Cadmium and Chromium makes disposal less critical. It is also not clear that batteries pose any greater risk than is currently accepted for fossil fuel based transport. Petrol and diesel powered transportation cause significant environmental damage in the form of spills, smog and distillation byproducts. SAFETY Firefighter s and rescue personnel receive special training to deal with the higher voltages encountered in electric and hybrid gas-electric vehicle accidents. FUTURE The future of battery electric vehicles depends primarily upon the availability of batteries with high energy densities, power density, long life, and reasonable cost as all other aspects such as motors, motor controllers, and chargers are fairly mature and cost competitive with ICE components. The most likely future for BEVs currently appears to be the incremental improvements needed for hybrids. Hybrid EVs are a smaller step from purely ICE driven cars, yet share much of the same core technology as true BEVs. As hybrids become more refined, battery life, capacity and energy density will improve and the combustion engine used less (particular with PHEV). At some point it may become economic for hybrids to be sold without their ICE, finally leading to BEVs being commonplace. Alternatively, if fuel cells make a breakthrough neither BEVs nor hybrids will be required. More likely fuel cells will replace the ICE in hybrid designs, providing a large energy density, whilst a more traditional battery pack provides the required power density. Li-ion , Li-poly and Zinc-air Batteries have demonstrated energy densities high enough to deliver range and recharge times comparable to conventional vehicles. Their greater cost has discouraged use in commercial BEVs, but as production increases for other markets BEVs will no doubt use them. Flywheel Energy Storage is a completely different form of electrical energy storage. It shares a lot with battery technologies and both batteries and flywheels are used in the same applications. Recent advances in materials and electronic control makes a flywheel 'BEV' a strong possibility. There have been prototype electric locomotives using flywheel storage. OWNERS The greatest fans of BEVs are those who have obtained or built and used them. This is a self-selected group because BEVs have not been promoted by the major manufacturers in the United States, so their enthusiasm may be misleading. Owners of conventional gasoline vehicles, once given the chance to live with an BEV often leave their gasoline cars sitting in the driveway. Spouses, luke warm when the vehicle is purchased often take over the vehicle from the purchaser once they use it. Fans point out the following:
CONTROVERSY In the USA, some EV fans have accused the three major domestic manufacturers, SUV . Of the various BEVs marketed by the "Big Three", only the General Motors EV1 (manufactured by GM) and the Th!nk City (imported and marketed by Ford) came close to being appropriate configurations for a mass market. However, at the end of their programs GM destroyed its fleet, despite offers to purchase them by their drivers. Ford's Norwegian-built "Th!nk" fleet was covered by a three-year exemption to the standard U.S. Motor Vehicle Safety laws, after which time Ford had planned to dismantle and recycle its fleet; the company was, however, persuaded by activists to not destroy its fleet but return them to Norway and sell them as used vehicles. Ford also sold a few lead-acid battery Ranger EV s, and some fleet purchase Chevrolet S-10 EV pickups are being refurbished and sold on the secondary market. The three major American motor companies have almost exclusively promoted their electric cars in the American market, where gas is comparatively cheap, and virtually ignored the European market, where gas is significantly more expensive. This can be seen as avoiding the market. Because of the much higher fuel costs, the latent demand for electric vehicles would presumably be higher in Europe, and the outcome of increased BEV sales, in turn, be more certain. Educational literature (for children) is still available that teaches that lead-acid batteries cannot store enough energy to make an electric vehicle practical. Though true, this statement is a lie through omission, as it ignores more advanced battery designs. Both Honda and Toyota also manufactured electric only vehicles. Honda followed the lead of the other majors and terminated their lease-only programs. Toyota offered vehicles for both sale and lease. While Toyota has terminated manufacture of new vehicles it continues to support those manufactured. It is actually possible to see a RAV-4 EV on the road but this is indeed a rare sight. A film on the subject, directed by former EV1 owner and activist, Chris Paine entitled Who Killed the Electric Car? premiered at the Sundance Film Festival and at the Tribeca Film Festival in 2006, and is scheduled to premiere theatrically in June. UNITED STATES The United States produced many electric automobiles, such as the Detroit Electric , during the early 20th century, but production dropped to insignificant numbers with the triumph of Gasoline powered Internal Combustion Engine vehicles in the 1920s . In recent years, electric vehicles have been promoted through the use of tax credits. In California , the California Air Resources Board attempted to set a quota for the use of electric cars, but this was withdrawn after complaints by auto manufacturers that the quotas were economically unfeasible due to a lack of consumer demand. However, many believe this complaint to be unwarranted due to the claim that there were thousands waiting to purchase or lease electric cars from companies such as General Motors , Ford , and Chrysler in which these companies refused to meet that demand despite their production capability. Others note that the original electric car leases were at reduced cost and the program could not be expected to draw the high volumes required without selling or renting the cars at a financial loss. Since the California program was designed by the California Air Resources Board to reduce air pollution and not to promote electric vehicles, the zero emissions requirement in California was replaced by a combination requirement of a tiny number of Zero-emissions Vehicle s (to promote research and development) and a much larger number of Partial Zero-emissions Vehicle s (PZEVs), which is an administrative designation for an ''super ultra low emissions vehicle'' (SULEV), which emits pollution of about ten percent of that of an ordinary low emissions vehicle. OUTSIDE THE UNITED STATES In London, electrically powered vehicles are one of the categories of vehicle exempted from the Congestion Charge . This is also true in all of Norway , where zero-emission vehicles are also allowed to use the Bus Lane . In most cities of the United Kingdom low speed Milk Float s (milk trucks) are used for the home delivery of fresh Milk . PRODUCTION VEHICLES Recent or current production battery electric vehicles sold or leased to fleets include:
PROTOTYPES Recent prototype EVs include:
PRODUCTION ANNOUNCEMENTS
HOBBYISTS, RESEARCH, AND RACING There is a minor industry supporting the Conversion and building of BEVs by hobbyists. Some designers point out that a specific type of electric vehicle offers comfort, utility and quickness, sacrificing only range. This is called a short range electric vehicle. This type may be built using high performance lead–acid batteries, but of only about half the mass that would be expected to obtain a 60 to 80 mile (100 to 130 km) range. The result is a vehicle with about a thirty mile (50 km) range, but when designed with appropriate weigh distribution (40/60 front to rear) does not require power steering, offers exceptional acceleration in the lower end of its operating range, is freeway capable and legal, and costs less to build and maintain. By including a manual transmission this type of vehicle can obtain both better performance ''and'' higher efficiency than the single speed types developed by the major manufactures. Unlike the converted golf carts used for Neighborhood Electric Vehicle s, these may be operated on typical suburban throughways (40 to 45 mph or 60 or 70 km/h speed limits are typical) and can keep up with traffic typical to these roads and to the short on and off segments of freeways that are common in suburban areas. Aside from production electric cars, often hobbyists build their own EVs by Converting existing production cars to run solely on electricity. Some even drag race them as members of NEDRA . Universities such as the University Of California, Irvine even go so far as to build their own custom electric or hybrid-electric cars from scratch. A non-profit program "CalCars" {Link without Title} at the University of California, Davis, is attempting to convert a hybrid Toyota Prius automobile to operate as a Plug-in Hybrid Electric Vehicle (PHEV) through the installation of additional batteries and software modifications. Such a vehicle will operate as would a pure electric for short trips, taking its power from household and workplace rechargers. For longer trips the vehicle will operate as it does at present—as a "strong" Hybrid Vehicle . A prototype (using sealed lead-acid batteries) is undergoing tests. It is expected that a production conversion would use a more advanced battery. (Advanced batteries are under development and soon for production in the support of hybrid vehicles.) They are currently soliciting donations of additional vehicles and funds for this project. Battery electric vehicles are also highly popular in quarter mile (400 m) racing. The National Electric Drag Racing Association regularly holds electric car races and often competes them successfully against exotics such as the Dodge Viper .
SEE ALSO
PATENTS
REFERENCES EXTERNAL LINKS
See also "http://www.driveclean.ca.gov" for an official California site on ZEV s and PZEV s. A page on this site, "http://www.driveclean.ca.gov/en/gv/vsearch/cleansearch.asp" will also list the available cars in various categories, especially informative if you are looking for an electrically powered city car (that page has no entries). EV NEWS STORIES
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