Electric car: Difference between revisions

Battery Electric Vehicles or BEVs are electric vehicles whose main energy storage is in the chemical energy of batteries.

BEVs are the most common of zero emission vehicles or ZEV passenger automobiles as recognized by the CARB. The electrical energy used to power the motors is most commonly obtained from a variety of battery chemistries arranged into Battery packs. It can also come from onboard hydrogen, fuel cells, and their support systems. For additional range genset trailers or pusher trailers are sometimes used. Batteries used in electric vehicles include Lead-acid, Absorbed Glass Mat, NiCD, Nickel metal hydride, Li-ion, Li-poly and Zinc-air batteries.

General Motors EV1

History

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. They 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 electric starter by Cadillac in 1913 which simplifying the difficult and sometimes dangerous task of starting the heat engine was the downfall of the electric vehicle, as 1912 may have been the pinical year for BEVs. Still others point out that it was radiators, in use as early as 1895 by Panhard-Levassor in their Systeme Panhard design [1], which allowed engines to keep cool enough to run for more than a few minutes, before which they had to stop and cool down at horse troughes along with the steamers. The truth may be that EV's had fallen out of favor over the mass produced Ford Model-T which when into production four years earlier in 1908. [2]

For more information on this subject, see history of the electric vehicle.

Efficiency

Production [3] and conversion battery electric vehicles regularly achieving 0.5 to 0.16 kWh per mile , divided by the number of passengers for per pm figures. The US fleet average of 23mpg is equivalent to 1.46 kWh/mile and the 70mpg Insight gets 0.48kWh/mile, assuming 33.6kWh per gallon of gasoline. Battery electric cars are thus very efficient as measured by recharging energy.

It is important to study the full effect of any vehicle design, especially when promoted as better than the status quo. 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 emissions 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.

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. 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.

Fuels

There are no currently available technologies that can provide the energy required over the life of a car. This means that all car technologies need to be refueled. If all the energy is stored in batteries refuelling means charging those 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.

Fuel Cell electric vehicles are a form of BEV where the battery chemicals can be provided externally to the reaction vessel. This means that refueling just requires replacement or replenishment of the stored fuel like a standard petrol bowser. In some designs, such as Hydrogen fuel cells the fuel is Hydrogen and the waste is water vented to the atmosphere. In a Vanadium redox fuel cell two liquids are reacted together to form a third which is then collected and separated back. Fuel cells, like batteries, only store energy extracted from somewhere else, the Hydrogen or Vanadium liquids are produced from other energy sources such as natural gas or wind power.

Range

The range of a BEV depends greatly on the amount 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 usuaily use lead-acid batteries because they are the most available and inexpensive, such conversions generally have 20 to 50 miles of range and are built to satisfy the drivers individual needs. Production EVs with lead-acid batteries are capable of up to 80 miles per charge. NiMH chemestries have high energy density and can deliver up to 120 miles of range. Lithium ion equipped EVs have demonstrated 300 miles of range per charge[4]. EVs can also use pusher trailers or genset trailers in order to function as a hybrid vehicle for occasions when unlimited range is desired without the additional weight durring normal short range use.

In practice most vehicle journeys are quite short, the majority being under 30km (20miles) per day. As fuel prices increase this will tend to become more marked. Thus, a BEV that can do 60km in a day is quite practical.

Charging the cells

The charging time is limited primarily by the capacity of the grid connection. A normal household outlet is between 1.5kW in the US to 3kW in countries with 240V supply. The main connection to a house might be able to sustain 10kW, and special wiring can be installed to use this. At this higher power level charging a even small 7kWh (14-28 mile) pack would probably require one hour. Compare this to the effective power delivery rate of an average petrol pump, about 5,000kW. Even if the supply power can be increased, most batteries do not accept charge at greater than their 'charge rate' C1.

Some recent handheld device battery designs by Toshiba [5] are claimed to be capable of accepting an 80% charge in as little as 60 seconds. Scaling this specific power characteristic up to the same 7kWh EV pack would result in the need for a peak of 336kW of power from some source for those 60 seconds. It is not clear that such batteries will work directly in BEVs as heat build-up may make them unsafe.

Most people do not require fast recharging because they have plenty of time (6 to 8 hours) during the work day or overnight to refuel. As the charging does not require attention it only takes seconds for an owner to plug-in and un-plug 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 providing suitable power. 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, 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 is no exposed conductors.

Battery life

Individual batteries are usually arranged into large Battery packs of various Voltage and Amp Hour products to give the required energy capacities. Battery life must be considered when calculating cost of opperation, as all batteries wear out and must be replaced. The rate at which they expire depends on a number of factors. Some of these factors are can be mitigated with a good Battery Management System and proper care.

The depth of discharge(DOD) is the recommended proportion of the total available energy storage for which that batter 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 with little degradation of their NiMH packs [6]. Jay Lenos 1912? Baker Electric still opperates on its original edison cells. Battery replacement costs may be offset by the lack of regular maintainance 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. Whilst these technologies are developed for small markets this is not a concern, but if production were scaled to match current car demand the risks may be 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

Firefighters and rescue personnel recieve 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 controlers, and chargers are fairly mature as cost competetive.

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.

Fans

The greatest fans of BEVs are those who have obtained and used them. Owing to the fact that BEVs have not been promoted by the major manufactures in the United States, this is a self-selected group, so their enthusiasm may be misleading. Fans point out the following:

• Short commutes are the norm, making range moot.

• People can take responsibility for their own energy production with renewables. This will reduce dependance on foreign oil and large scale coal mining. Many electric vehicle owners and operators express great satisfaction in this aspect of electric vehicle use, even while acknowledging that this use can have only little effect on these matters unless adopted more widely and produced in greater quantities.

• Battery electric vehicles are quieter than ICE powered vehicles.

• BEVs do not produce noxious fumes around the car.

• With greater demand battery packs can be standardised and handled in both a safe and environmentally responsible way.

• If packs were mass produced the charging time can be increased by swaping the pack over with the charger. (This is not practical currently as the battery packs are far too heavy to handle without special tools)

• It is possible to rapidly charge battery through 'Dump charging', which might become available in the same way that petrol stations are.

Controversy

Some USA EV fans have accused the three major domestic manufactures, General Motors, Chrysler Corporation and Ford Motor Company of deliberately sabotaging their own electric vehicle efforts through several methods: failing to market, failing to produce appropriate vehicles, failing to satisfy demand, and using lease-only programs with prohibitions against end of lease purchase. By these actions they have managed to terminate their BEV development and marketing programs despite operator's offers of purchase and assumption of maintenance liabililties. They also point to the Chrysler "golf cart" program as an insult to the marketplace and to mandates, accusing Chrysler of intentionally failing to produce a vehicle usable in mixed traffic conditions. The manufacturers, in their own defense, have responded that they only make what the public wants. EV fans point out that this response is the same argument used by GM to justify the intensively promoted 11 mpg 6500 lb (2,950 kg) Hummer H2 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 EVs, and some fleet purchase Chevrolet S-10 EV pickups are being refurbished and sold on the secondary market.

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.

United States

File:Detroit Eletric ad.jpg

1912 Detroit Electric

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 vehicles (to promote research and development) and a much larger number of partial zero-emissions vehicles (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.

International

In London, electrically powered vehicles are one of the categories of vehicle exempted from the Congestion Charge. Similarily in all of Norway, where zero-emission are also allowed to use the bus lane.

Productions

Recent or current production battery electric vehicles sold or leased to fleets include:

• AC Propulsion TZero (Last of four being completed for sale)
• Arton Birdie
• Bertone Blitz
• Citroën Berlingo Electrique
• Chevrolet S10 EV (Some sold to fleets, available on secondary market as refurbished vehicles)
• Chrysler Epic
• Commuter Cars Tango
• Corbin Sparrow (A number produced and sold, not presently in business, may be revived)
• Elcat (1985-2002, almost all vehicles in second-hand use)
• Ford Ranger EV (1998-2003, some sold, most leased and recovered and destroyed)
• General Motors EV1 (Several hundred produced for lease only, all recovered, most destroyed)
• Honda EV Plus (Several hundred produced for lease only, all recovered, most destroyed)
• Hyundai SantaFe EV
• Kewet
• Citicar/CommutaCar/Comuta-Van
• Nissan Altra
• Porsche 550 Spyder replica electric conversion
• Peugeot 106 EV
• Peugeot Partner
• Pivco City Bee
• Renault EV
• REVA May be imported as a speed limited NEV
• Sinclair C5
• Solectria Force (Conversion, not currently in production)
• Think City (Norwegian import by Ford, lease only, all recovered and returned to Norway)
• Toyota RAV4 EV (Rare, some leased and sold on US East and west coast, out of production, supported)
• Twike
• Universal Electric Vehicle Corporation Electrum series Spyder, Com V-3
• Zebra Model Z roadster (Formerly Renaissance Tropica)
• Zytec Lotus Elise

Prototypes

Recent prototype EVs include:

• Cree SAM
• Ford E-Ka
• Lexus EV (Featured in the film Minority Report)
• Pinanfarina Ethos II
• Renault EV Racer
• Solectria Sunrise
• Subaru Zero EV
• Suzuki EV Sport
• Volvo 3CC Three seater with lithium ion batteries [7]

Production announcements

• Venturi "Fetish" sports car to use AC propulsion components [8] (Flash animation with music background)
• AC propulsion announces plans to convert Toyota Scion xA and xB vehicles[9] (items 8 and 9).
• The Japanese automobile manufacture Mitsubishi announced in May 11, 2005 that it will become a battery electric vehicle producer, to be in test fleets in 2006 and with production models available in 2010[10]. They expect a 93 mile range using lithium-ion batteries. Target price is around USD 19,000 (although no export decision has been made)[11].

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 range. The result is a vehicle with about a thirty mile 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 vehicles, these may be operated on typical suburban throughways (40 to 45 MPH 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"[12] 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.

• Japanese Prof. Dr. Hiroshi SHIMIZU from Faculty of Environmental Information of the Keio University created the limousine of the future: the Eliica (Electric Lithium Ion Car) has 8 wheels with electric 55 kW hub motors (8WD) with an output of 470 kw and zero-emission. With a top speed of 190 km/h and a maximun reach of 320 km provided by lithium-ion-batteries. See the video at [13]
• German Umweltbrief [14] want to convert an old-timer car into full electric drive with 4 wheel hub motors; a retro car for the 21th century called electro4. This drive is nearly free of abrasion and maintenance and very reliable. Further advantages are optimal capability of acceleration and best traction through individual control of the wheels. Also the power is generated in the place where its used. Gearbox, kardan shaft and drive shaft become unnecessary, which means less weight. Even an old car can get a torque power of 1000 Nm! This 4WD is very silent. There is no vibration and no motor cold-running, the full energy is available immediately. Also small cars can get this system. All is combinable with anti-block-system, anti-slip-system, stability-system etc., climate control with a/c, heating/cabin, pre-conditioning etc. [15]

See also

• Electric boat
• Electric vehicle conversion

External links

• Electric Auto Association
• EV Photo Album, over 500 Global EVs and conversions
• USA National Electric Drag Racing Association Website
• EV World
• Elektromobil.com - German Site for EVs in Europe
• Electrifying Times
• European Electric Road Vehicle Association
• Electric Vehicle Council of Ottawa - EVCO
• Electric Drive Transportation Association
• Alternative Fuels Data Center
• EV Project
• evchallenge: Smart Kids, Clean Cars, Green World
• Megawatt Motorworks
• AC Propulsion Inc
• The Hydrogen Expedition Around the world on an electric vehicle
• Cree SAM website
• List of EV Lists
• Electric Vehicle Discussion List for owners and builders of conversions and other EVs
• Many Many More Links
• EV Supersite The world's largest online electric vehicle conversion diary. This popular site sees visitors from between 8 to 16 time zones per day. Hundreds of fully illustrated web pages describe the conversion of a Saturn sedan to an emissions-free battery-electric vehicle. Comprehensive and informative...
• EV engineer Steven Kent's site promoting his self published book, Kar Kaptains Kry, "Kalamity!" This book, the first of three, describes and justifies the short range high performance EV and another type combining internal combustion and mains-recharged batteries that he calls a "glider" (now commonly called a "plug in hybrid") and includes engineering and marketing analysis for mass production.
• Alternative Fuel Vehicle Training From the National Alternative Fuels Training Consortium.

See also "http://www.driveclean.ca.gov" for an official California site on ZEVs and PZEVs. 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

• San Francisco Chronicle: Owners charged up over electric cars, but manufacturers have pulled the plug 4/24/2005
• The Air We Breathe, The Cars We Drive, 2004
• The Electric-Car Slide, October 22, 2003
• Slim Fit For The Freeways Oct 2, 2003
• tzero earns a 3.40 GPA Sept. 29, 2003
• Stopping Traffic, Rick and Bryans Tango July 27, 2003
• tZero exciting article in NY Times Sep 20, 2003