Glossary of Terms

by Chris Raley
April 2002

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Alternating Current (AC): Reverses its direction of flow at regular intervals-usually 60 times a second--from positive to negative. The most efficient electric motor uses AC.
Alternative Fuel Vehicle (AFV): Any dedicated or dual-fueled vehicle according to the Energy Policy Act.
Alternative Fuels Utilization Program (AFUP): Managed by the Department of Energy it aims to improve national energy security and air quality by developing use of alternative fuels and alternative fuel vehicles.
Ampere/Amperage (Amp): The standard unit of measurement for electric current.
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Battery: A container that produces Direct Current (DC) by chemical reaction and storing energy.
Battery Council International (BCI): Determines standards such as group sizes that specify external dimensions.
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Cell: The basic unit used to store energy in a battery.
Charge/Charging: Powering a battery back to full capacity.
Charging Station: The place or device that connects an EV to a power source for charging.
Conversion EV: A gas vehicle that was converted to an EV.
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Deep Discharge: Indicates the loss of a significant percentage of the battery's capacity (50% or more).
Direct Current (DC): Flows continuously in one direction.
Discharge Rate: The rate at which the battery discharges power.
Driveline Efficiency: The amount of energy produced in an engine for propulsion.
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Electric Vehicle (EV): A vehicle powered by electricity.
Electrode: The conductor by which electrical current enters or leaves a non-metallic medium.
Electrolyte: The medium in which the movement of ions determines the current flow.
Energy Density: The amount of energy a fuel source can contain.
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Flexible Fuel Vehicle (FEV): Can run on a mix of two fuel types (for example gasoline and alcohol) or a combination of two fuel types (for example gasoline and compressed natural gas).
Flooded Cell: A lead-acid battery design in which the ordinary liquid solution of acid is the electrolyte.
Fuel Cell: An electrochemical engine that converts the energy of a fuel and an oxidant, directly to electricity. For example, hydrogen and oxygen.
Fuel Cell Vehicle (FCV): A vehicle powered by a fuel source through a fuel cell.
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Gel Cell: A type of lead acid battery in which the electrolyte solution comes in gel form instead of liquid.
Grid Electricity: that comes from a utility and is inexpensive and can come from a renewable resource.
Gross Vehicle Weight (GVW): The maximum allowable weight of the vehicle and payload.
Ground Fault Interrupter (GFI): Breaks the current flow when a circuit has a leak to ground.
Group Size: The set of standard external dimensions for batteries set by the BCI.
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Horsepower: The rate at which an engine produces energy.
Hybrid Vehicle: Has electric components, but uses a non-grid fuel source.
Hydrometer: Tests the specific gravity of a fluid.
Hygrometer: Measures air humidity.
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Inductive Charging: A charging system that uses magnetic coupling devices and not metal-to-metal contact plugs.
Infrastructure: Refers to all the parts of a vehicle that make it an Electric Vehicle, except the vehicle itself.
Inverter: Converts DC electricity into AC electricity so it can be used by a motor.
Ion: An electrically charged particle or molecule.
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Kilowatt (kW): The standard unit by which electric power capacity is measured. One kilowatt is equal to 1000 watts.
Kilowatt-Hour (kWh): The standard unit of measurement of large quantities of energy consumed over time.
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Lead-Acid Battery: Consists of several cells put in a series in a polypropylene container and uses lead oxide and spongy lead electrodes with sulfuric acid as an electrolyte. These are normally found in automobiles.
Lithium Polymer Battery: Uses lithium for an electrochemically active material, and the electrolyte is a polymer or polymer-like material that conducts lithium ions.
Lithium-Ion Battery: Uses an electrochemically active material and an electrolyte liquid which conducts lithium ions.
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Miles Per Kilowatt-Hour (MPkWh): The fuel efficiency unit of measurement.
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N Hour Rate: The length of time it takes to discharge a fully charged battery at a constant current.
Neighborhood EV (nEV): An EV that is not for highway use because it operates below highway speeds.
Nickel Metal Hydride Battery: Composed of nickel hydroxide and a multicomponent, engineered hydride alloy consisting of vanadium, titanium, zirconium, nickel, and minor quantities of other metals. It is non-toxic and completely recyclable.
Nickel-Cadmium Battery: Uses potassium hydroxide as the electrolyte with a nickel and cadmium electrode. Often held in a polypropylene container, these batteries are also often used in automobiles.
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Ohms: The unit of resistance. A constant current of one ampere in a conductor produces one volt between the conductor's ends.
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Parallel Drivetrain: Includes in a parallel vehicle an engine, batteries, and a motor and is called parallel because both the motor and the engine can move the vehicle.
Parallel Starter/Alternator: The motor can act as a starter and an alternator.
Photovoltaic: Converts solar energy to electrical energy. They are also called Solar Cells.
Power: In the case of an electric vehicle, a measure of acceleration or the rate at which energy is released and is measured in kilowatts.
Power Density: The rated power per unit volume in a battery, measured in watts per liter (w/l).
Powertrain: Includes the components of a drive train with the addition of an electrical power inverter and/or controller and converts electrical energy into mechanical energy.
Production EV: An EV that was made by an auto manufacturer.
Propulsion System: Converts stored electrical energy into mechanical energy through the combination of the power train and battery system.
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Range: The distance an EV can travel on a battery.
Rate of Charge: The amount of energy being added to the battery per a unit of time.
Regenerative Braking: Recharges the batteries from the friction created by braking.
Renewable Energy (RE): Comes from sources that can be renewed, such as solar, wind, hydro, geothermal, tidal, wave, and biomass.
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Sealed Lead-Acid Battery: The battery has a special mat material located between the plates so that no free liquid exists.
Series Drivetrain: Includes a fuel converter, a generator, batteries and a motor. The motor moves the vehicle and the fuel converter converts mechanical energy into electrical energy through the generator.
Specific Energy: The rated energy per unit weight of a battery in watt-hours per kilogram.
Specific Power: The rated power per unit weight of a battery in watts per kilogram.
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Torque: The amount of twisting force that makes the wheel turn.
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Volt: A unit of measurement for electromotive force. Watts divided by volts equals amps.
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Watt: The unit of electrical power.
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Zero Emission Vehicle (ZEV): A vehicle that does not emit pollutants.
Zinc-Air Battery: Has potassium hydroxide as the electrolyte with a zinc electrode and an air electrode.

Chris Raley is a freelance writer and technology enthusiast.