High Energy Batteries 325

array

A group of individual battery cells connected in series. Battery arrays are encased in modules as part of EV battery packs.

batteries

A device that converts chemical energy into electrical energy. Batteries consist of multiple individual cells, each of which contains a cathode, an anode, and an electrolyte.

battery management system

BMS. A computer that monitors, regulates, and coordinates the operations of a battery pack. The battery management system in an EV may be either centralized or distributed.

battery pack

A group of battery cells connected together to produce large amounts of electrical energy. Battery packs may also include components such as sensors and battery management systems.

BMS

Battery management system. A computer that monitors, regulates, and coordinates the operations of a battery pack. The BMS in an EV may be either centralized or distributed.

carbon monoxide

A colorless, odorless, poisonous gas made of carbon and oxygen. Carbon monoxide may be emitted by Li-ion batteries that catch fire.

cells

A single unit of a battery. A cell contains a cathode, an anode, and an electrolyte solution.

centralized

Controlled from a single location or by a single device or authority. A centralized BMS consists of a single computer connected to a battery pack.

chain reaction

A sequence of events that occurs when the results of one reaction trigger more reactions of the same type. Chain reactions like thermal runaway in Li-ion batteries can create serious safety hazards.

chemical energy

The energy created by a reaction between two or more substances. Chemical energy is stored in batteries.

chemical reaction

A process in which one or more substances are changed into another substance or substances. Chemical reactions allow batteries to produce electricity.

circuit

A completely enclosed path for electrical current. Electrical circuits usually include a source, path, load, and control.

cooling mechanism

A device that removes heat from an electrical system in order to regulate temperature. Cooling mechanisms in EV battery packs work by circulating either air or liquid coolant.

cycle life

The total number of times a secondary cell battery can be discharged and recharged before it must be replaced. Cycle life depends on the battery's design, materials, and operating conditions.

diagnostic

A set of computer instructions that helps users or technicians investigate or analyze the cause or nature of errors or failures. Diagnostics performed by a BMS can help identify the cause of problems such as overheating.

discharge cycle

The chemical reaction process of a battery. The discharge cycle is complete when a battery can no longer react to produce voltage.

distributed

Controlled from multiple locations or by multiple devices or authorities working together. A distributed BMS consists of several small computers located within each module of a battery pack.

drones

An aircraft without any human pilot, crew, or passengers on board. Drones, also known as unmanned aerial vehicles, may be remotely piloted or fully autonomous.

electric shock

The flow of electricity through the body. Severe electric shock can be fatal.

electric vehicles

EVs. A vehicle that is propelled by an electric motor that draws its power from a battery. Electric vehicles, including hybrid electric vehicles, require high energy, lightweight, rechargeable batteries.

electrical energy

The energy created by the movement of electrons. Electrical energy can be converted into light, heat, or motion.

energy

The ability to do work. Energy comes in many forms, including electrical, mechanical, thermal, and chemical energy.

energy density

The amount of energy that a battery can supply per unit of volume. Energy density is measured in watt-hours per liter (Wh/l).

EVs

Electric vehicles. A vehicle that is propelled by an electric motor that draws its power from a battery. EVs, including hybrid electric vehicles, require high energy, lightweight, rechargeable batteries.

fuse

A safety device that opens a circuit when it detects excess current. A fuse often has a component that melts to open the circuit.

gasoline engines

A type of internal combustion engine that generates power by burning fossil fuels. Gasoline engines are widely used in personal vehicles, aircraft, and boats.

HEVs

Hybrid electric vehicles. A vehicle powered by two different sources: an electrical system and a conventional gasoline engine. HEVs use much less gasoline than conventional gas-powered vehicles.

hybrid electric vehicles

HEVs. A vehicle powered by two different sources: an electrical system and a conventional gasoline engine. Hybrid electric vehicles use much less gasoline than conventional gas-powered vehicles.

hydrogen

A colorless, odorless gas that is the most abundant element on the planet. Pure hydrogen gas is extremely flammable.

kilowatt

kW. A unit used to measure electrical power that is equal to one ampere multiplied by 1,000 volts. One kilowatt is equal to 1,000 watts.

kilowatt-hours

kWh. A unit used to measure electrical energy usage or delivery over time. One kilowatt-hour indicates that a battery can supply 1,000 watts of electricity for one hour.

kWh

Kilowatt-hours. A unit used to measure electrical energy usage or delivery over time. One kWh indicates that a battery can supply 1,000 watts of electricity for one hour.

laptops

A small, portable personal computer with an attached keyboard. Laptops typically use lithium-ion or lithium polymer batteries.

lead-acid batteries

A type of secondary cell battery that uses lead dioxide as a cathode and lead as an anode. Lead-acid batteries are very cheap to produce and therefore widely used despite their lower energy, power, and cycle life.

Li-ion batteries

Lithium-ion batteries. A type of secondary cell battery that uses a lithium compound as a cathode and usually graphite or carbon as an anode. Li-ion batteries are widely used in portable electronics and electric vehicles.

lithium-ion batteries

Li-ion batteries. A type of secondary cell battery that uses a lithium compound as a cathode and usually graphite or carbon as an anode. Lithium-ion batteries are widely used in portable electronics and electric vehicles.

module

A unit that contains several battery cells connected in either series or parallel. Modules in EV battery packs also contain fuses, sensors, and cooling mechanisms.

motors

A machine that converts one form of energy into another. Motors often transform electrical energy into mechanical energy.

nickel-metal hydride batteries

NiMH batteries. A type of secondary cell battery that uses nickel hydroxide as a cathode and a hydrogen alloy as an anode. Nickel-metal hydride batteries are cheaper than Li-ion batteries and are used in some hybrid electric vehicles.

NiMH batteries

Nickel-metal hydride batteries. A type of secondary cell battery that uses nickel hydroxide as a cathode and a hydrogen alloy as an anode. NiMH batteries are cheaper than Li-ion batteries and are used in some hybrid electric vehicles.

passenger compartments

The area in a vehicle where operators and passengers sit. In EVs, battery packs are often located under passenger compartments.

personal protective equipment

PPE. Any article of clothing or device worn to minimize exposure to hazards and prevent injury. Personal protective equipment may include safety glasses, gloves, earplugs, respirators, or steel-toed boots.

power

The rate at which a device converts energy from one form to another, such as converting electrical energy into light or movement. Power is measured in watts (W).

power density

The amount of power that a battery can supply per unit of volume. Power density is measured in watts per liter (W/l).

primary cell batteries

A battery that cannot be recharged. Primary cell batteries are usually thrown away once their charge is spent.

renewable energy

Energy that is naturally and continually replenished without being depleted. Renewable energy sources include sunlight and wind.

safety data sheet

SDS. A document of mandatory information that must accompany hazardous workplace chemicals. A safety data sheet includes details such as risks, precautions, and first aid procedures associated with the chemical.

secondary cell batteries

A battery that can be recharged. Secondary cell batteries are charged by running electrical current back through them to restore their chemical energy.

self-discharge rate

The amount of energy a battery loses over a specific amount of time when it is not connected to a circuit. Self-discharge rate is usually expressed in percentage of total energy lost per month.

sensors

A device that detects a change in physical and environmental conditions and sends out an electric signal in response. Sensors in a battery pack may be used to track variables such as temperature, voltage, and state of charge.

service disconnect

A plug or switch that electrically isolates the battery pack from the rest of a vehicle's systems when activated. The service disconnect should be activated before beginning maintenance or repair work.

service life

The length of time a battery is expected to operate before it must be replaced. The service life of a rechargeable battery is determined by its cycle life, self-discharge rate, materials, and operating conditions.

smartphones

A mobile device able to connect to and send data across the internet. Smartphones are used for phone calls, texting, internet browsing, and many other functions.

solar power

Electrical energy generated by sunlight. Solar power is a form of renewable energy.

specific energy

The amount of energy that a battery can supply per unit of weight. Specific energy is measured in watt-hours per kilogram (Wh/kg).

specific power

The amount of power that a battery can supply per unit of weight. Specific power is measured in watts per kilogram (W/kg).

state of charge

SoC. The amount of energy currently contained in a battery. State of charge is usually given as a percentage where 100% means that the battery is fully charged.

tablets

A small, portable personal computer with a touchscreen interface. Tablets are generally smaller than laptops but larger than smartphones.

thermal runaway

The process of a defective or damaged battery cell overheating and damaging nearby cells, causing them to also overheat. Thermal runaway can cause fires or explosions if not detected and stopped.

unmanned aerial vehicles

UAVs. An aircraft without any human pilot, crew, or passengers on board. Unmanned aerial vehicles, also known as drones, may be remotely piloted or fully autonomous.

voltage

The electrical force or pressure that causes current to flow in a circuit. Voltage is measured in volts (V).

volts

V. A unit of measurement that indicates the amount of electrical force or pressure in a circuit. Volts measure voltage, which is also known as electromotive force.

volume

The amount of three-dimensional space that an object occupies. Volume is measured in cubic feet or gallons in English units and in liters or cubic meters in metric units.

watts

W. A unit used to measure electrical power that is equal to one ampere multiplied by one volt. A watt is 1/1,000th of a kilowatt.

wind power

Electrical energy generated by the movement of wind turbines. Wind power is a form of renewable energy.