Our Glossary of Battery Terms. This list of technical terms is our Glossary to help you understand commonly used technical language in the battery industry.
Glossary Of Battery Terms
Here’s the list.
Active material refers to the substances in a battery that participate in electrochemical reactions, producing and storing electrical energy.
Absorbent Glass Mat (AGM)
Absorbent Glass Mat (AGM) is a type of lead-acid battery where the electrolyte is absorbed by a glass mat, providing higher performance and minimal maintenance.
A different form of the same element with different properties. Allotropes affect battery performance and safety, especially for lithium batteries.
Ambient temperature is the temperature of the surrounding environment where a battery is used or stored.
An Ampere (A) is a unit of electrical current representing the flow of one coulomb of charge per second.
Ampere-hour (Ah) is a unit used to measure a battery’s capacity, indicating the amount of current a battery can deliver for one hour.
An anode is the electrode in a battery where oxidation occurs, releasing electrons to the external circuit. When a device is powered, the anode carries a positive charge. But when the device is discharging, and power is being removed, the anode assumes a negative charge.
Absolute state-of-charge, which is the percentage of charge a battery can hold when it is new. ASoC decreases as the battery ages and loses capacity.
Absolute state-of-health, which is the percentage of energy a battery can store when it is new. ASoH decreases as the battery degrades and loses energy.
Balancing is the process of equalizing the charge or discharge rates of individual cells within a battery pack to maintain uniform performance.
An international treaty that reduces the movement of hazardous waste between countries. The Basel Convention covers waste batteries, which can contain toxic and harmful substances.
A battery is a device that stores electrical energy through a chemical reaction and converts it back into electrical energy when needed.
Battery Directive 2006/66/EC
European legislation regulating the production, distribution, use, and disposal of batteries and accumulators. The Battery Directive sets limits on the use of certain heavy metals in batteries and promotes recycling.
BESS stands for Battery Energy Storage System, a system used for storing energy through the use of batteries.
Bluetooth is a wireless technology used for short-range communication between electronic devices, often used to monitor and control battery systems via smartphones and tablets.
BMS, or Battery Management System, is an electronic system designed to monitor and manage battery performance, protecting it from damage and optimizing its lifespan.
C is a term used to describe a battery’s discharge rate or charging current, often represented as a multiple of the battery’s capacity (e.g., 1C, 2C, 5C).
Calendar life refers to the total lifespan of a battery, considering factors such as aging and environmental exposure.
Capacity is a measure of the amount of electrical energy a battery can store, typically expressed in ampere-hours (Ah) or watt-hours (Wh).
A correction factor that accounts for the reduced capacity of a battery when discharged at a higher C-rate than specified. Capacity offset increases with higher discharge rates and lower temperatures.
A gas that is produced as a by-product of some battery chemistries, such as lead-acid and zinc carbon. Carbon dioxide can cause corrosion, swelling, and pressure build-up in batteries if not properly vented or recombined.
A toxic gas that is produced as a by-product of some battery chemistries, such as nickel-cadmium and nickel metal hydride. Carbon monoxide can cause health hazards and fire risks if not properly vented or recombined.
A cathode is the electrode in a battery where reduction occurs, gaining electrons from the external circuit. When discharging, the cathode takes on a positive charge, and when charging, the cathode’s polarity is reversed and becomes negatively charged.
Cold Cranking Amps is a measure of the current that a battery can deliver at 0°F (-18°C) for 30 seconds while maintaining a voltage of at least 7.2 volts for a 12-volt battery. CCA is an indicator of the starting performance of a battery, especially for automotive applications.
Constant Current Constant Voltage is a charging method that applies a constant current to the battery until it reaches a certain voltage, then switches to a constant voltage until the current drops to a certain level. CCCV is a common charging method for lithium-ion batteries.
Code Division Multiple Access is a cellular network technology that uses codes to separate multiple signals at the same frequency. CDMA requires batteries to have high power density and low impedance to handle the high peak currents.
Coulombic efficiency is the ratio of the charge that can be extracted from a battery to the charge that was put into the battery during charging. CEC is affected by factors like temperature, rate, depth of discharge, and battery age.
A cell is the basic building block of a battery, consisting of an anode, a cathode, and an electrolyte. The voltage of a cell in a lead acid battery is 2 volts, whereas the voltage of a LiFePO4 cell is a nominal 3.2 volts.
A process that equalizes the voltages and capacities of the cells in a battery pack to improve the performance and longevity of the pack. Passive methods, like resistors or diodes, or active methods, like converters or transformers, can achieve cell balancing.
A process that selects cells with similar characteristics, like voltage, capacity, and internal resistance, to form a battery pack. Cell matching can improve the performance and longevity of the pack by reducing the stress and imbalance among the cells.
A condition that occurs when a cell in a battery pack is discharged below zero voltage and becomes reverse-charged by the other cells in the pack. Cell reversal can damage the cell and reduce the capacity and safety of the pack.
The voltage difference between the positive and negative terminals of a cell. Cell voltage is determined by the electrochemical potential of the cell chemistry and the state of charge of the cell. Cell voltage varies with the charge and discharge rate, temperature, and age of the cell.
Charge refers to the process of transferring electrical energy to a battery, resulting in the storage of energy in the form of a chemical reaction.
The ability of a battery to accept and store charge during charging. Charge acceptance is influenced by things like temperature, state of charge, depth of discharge, and battery age. Charge acceptance decreases as the battery approaches full charge or low temperature.
The ratio of the energy that can be extracted from a battery to the energy that was put into the battery during charging. Charge efficiency is affected by things like temperature, rate, depth of discharge, and battery age. Charge efficiency decreases as the battery approaches full charge or high temperature.
The percentage of charge that a battery can hold compared to its current capacity. The charge level is also known as the relative state of charge. Charge level is different from absolute state of charge, which is the percentage of charge that a battery can hold compared to its maximum capacity when it is new.
The ability of a battery to retain its charge when not in use. Things like temperature, state of charge, depth of discharge, and battery age influence charge retention. Charge retention decreases as the battery approaches full charge or high temperature.
A set of rules or instructions that determines how a charger delivers current and voltage to a battery. The charging algorithm is designed to optimize the charging performance and safety of a battery. The charging algorithm varies with the battery chemistry, size, and application.
Current Interrupt Device is a safety mechanism that disconnects the current flow in a battery when the internal pressure exceeds a certain limit. CID is used to prevent overcharge, over-discharge, short circuit, or thermal runaway in batteries.
Camera & Imaging Products Association is an international organization that establishes standards and guidelines for the camera and imaging industry. CIPA provides a standardized method for measuring the battery life of digital cameras based on typical usage patterns.
Closed Circuit Voltage Test
Closed Circuit Voltage Test is a method for testing battery performance by measuring voltage while the battery is connected to a load and discharging.
Compressed Natural Gas is a fuel that consists of mostly methane and is stored under high pressure. CNG is used as an alternative to gasoline or diesel in vehicles. CNG requires batteries to have high power density and low impedance to handle the high peak currents.
A Carbon Nanotube is a cylindrical structure of carbon atoms with a diameter of a few nanometers and a length of up to several micrometers. CNT has exceptional electrical, thermal, and mechanical properties and can be used as an electrode material or additive in batteries to enhance the performance and safety of batteries.
A Coulomb (C) is a unit of electrical charge equivalent to the amount of charge transferred by a current of one ampere in one second.
Coulombic efficiency is the ratio of the total charge removed from a battery during discharge to the total charge added during charging.
The losses of charge and energy that occur during the charge and discharge of a battery due to internal resistance, leakage, and side reactions. Coulombic losses reduce the coulombic efficiency and capacity of a battery.
The Central Processing Unit is the main component of a computer that executes instructions and performs calculations. CPU requires batteries to have high energy density and low self-discharge to provide long run time and standby time.
The temperature at which a battery undergoes a rapid and irreversible change in its performance, safety, or structure. Critical temperature can be caused by overcharge, over-discharge, short circuit, or external heat. Critical temperature can lead to thermal runaway, venting, or explosion in batteries.
A conductive material that collects and distributes the current from or to the electrodes in a battery. The current collector is usually made of metal foils, like copper for the negative electrode and aluminum for the positive electrode. The current collector affects the electrical and thermal performance of a battery.
The amount of current per unit area of an electrode or a current collector. Current density is expressed in amperes per square meter (A/m2) or amperes per square centimeter (A/cm2). Current density affects the electrochemical reactions, heat generation, and polarization of a battery.
Cut-off voltage is the voltage level at which a battery is considered fully discharged or charged, depending on the context.
A cycle is the process of charging a battery and then discharging it to a pre-determined level, typically considered one full cycle.
The total number of cycles a battery can provide before reaching the end of its life.
Discharge current is the current that flows out of a battery when it delivers power to a load. DCA is measured in amperes (A) or milliamperes (mA) and depends on the resistance and power demand of the load. DCA affects the discharge rate, voltage, and capacity of the battery.
A DC-to-DC converter is an electronic device that changes the voltage of a direct current source to match the requirements of a load or battery. It’s often used in electronic devices to regulate voltage.
A dedicated charging port (DCP) is a USB port that is solely designed for delivering power to a device and does not support data transfer. It is used for charging a variety of devices including smartphones, tablets, and cameras. Typically, a DCP can deliver up to 1.5 A of current at 5V, making the charging process efficient and fast.
Deep cycle refers to a type of battery designed for repeated discharge and recharge cycles, often down to a significant depth of discharge.
Depth of Discharge (DOD)
Depth of Discharge (DOD) is a measure of the amount of energy discharged from a battery. It is usually expressed as a percentage of the battery’s total capacity.
Direct Current (DC)
Direct current (DC) is the unidirectional flow of electric charge used by batteries during energy storage and output.
A battery converts chemical energy into electrical energy to power a device through an external circuit. As it does so, the battery discharges.
The pattern of voltage, current, and temperature changes that occur during the discharge of a battery. The discharge signature can be used to identify the type, state of charge, and state of health of a battery. Discharge signature can also be used to detect faults and anomalies in a battery.
Drain refers to the loss of charge from a battery, either due to usage or self-discharge over time.
The weight of a battery without electrolyte. Dry weight is used to compare the mass of different types of batteries.
The ratio of the time a battery is discharged to the total time of a charge-discharge cycle. The duty cycle affects the performance and lifespan of a battery.
The Engine Control Unit is a computer that controls the engine and other systems of a vehicle. The ECU is connected to the battery and regulates the charging and discharging of the battery.
Electric double-layer capacitor: A device that stores electrical energy by creating an electric field between two electrodes separated by an electrolyte. An electric double-layer capacitor is another name for a supercapacitor. An electric double-layer capacitor has high power density, fast charging and discharging, and long cycle life.
Electrochemical Impedance Spectroscopy is a technique that measures the impedance of a battery or a cell as a function of frequency. EIS can provide information about the internal resistance, charge transfer, diffusion, and other processes of a battery.
An electrode is a conductor through which electricity enters or leaves a battery, typically made of metal.
The electrolyte is a medium that allows the flow of ions between the anode and cathode in a battery, facilitating the electrochemical reaction.
End of Charge Voltage
End of Charge Voltage is the voltage level at which a battery is considered fully charged, and the charging process should be terminated.
Energy density is a measure of the amount of energy stored per unit volume or mass of a battery.
The ratio of the output energy to the input energy of a system. Energy efficiency indicates the amount of energy that is lost or wasted during a process. Energy efficiency can be improved by reducing the internal resistance, heat generation, and side reactions of a battery.
Energy storage system
A system that uses batteries or other devices to store and supply electrical energy to a load or a grid. Energy storage systems can provide backup power, peak shaving, frequency regulation, and renewable integration.
Equivalent Series Resistance (ESR)
Equivalent Series Resistance (ESR) is a measure of the internal resistance within a battery, contributing to power loss during energy transfer.
Electric vehicle supply equipment: a device that connects an electric vehicle to an external power source. EVSE is also known as a charging station or a charger. EVSE can have different levels of power and charging modes.
Fuel cell electric vehicle: a type of electric vehicle that uses a fuel cell to convert hydrogen and oxygen into electricity. FCEV has a battery that stores the excess electricity from the fuel cell and provides power to the motor. FCEV emits only water as a by-product.
Federal Communications Commission, a US government agency that regulates the communications industry. FCC sets standards and rules for the use of radio frequencies, wireless devices, and electromagnetic interference. FCC requires batteries and chargers to comply with its regulations.
Field-effect transistor: a type of transistor that uses an electric field to control the flow of current. A FET is used in electronic circuits and devices, such as switches, amplifiers, and sensors. It can also be used as a protection device for batteries.
Float charge is a maintenance charging state applied to a battery to compensate for self-discharge and keep it fully charged.
A type of rechargeable battery that uses liquid electrolytes stored in external tanks. The flow battery pumps the electrolytes through a cell stack where the electrochemical reactions take place. A flow battery has high energy density, long cycle life, and flexible design.
A type of electrochemical cell that produces electricity by a spontaneous chemical reaction between two electrodes and an electrolyte. A galvanic cell is also known as a voltaic cell or a primary cell. It cannot be recharged and has a limited lifespan.
Gas recombination is a process in sealed lead-acid batteries where hydrogen and oxygen gases generated during charging are recombined to form water, reducing water loss and maintenance requirements.
A type of nanomaterial that consists of a single layer of carbon atoms arranged in a hexagonal lattice. Graphene has high electrical conductivity, mechanical strength, and thermal stability. It is used as an additive or a coating for electrodes and separators in batteries to improve the performance and safety of the battery.
Hydrogen: a chemical element that has one proton and one electron. Hydrogen is the most abundant element in the universe and can be used as a fuel for vehicles and power generation. Hydrogen can be stored in tanks or in metal hydrides and can be converted into electricity by a fuel cell.
Water: a compound that consists of two hydrogen atoms and one oxygen atom. Water is essential for life and can be used as an electrolyte for batteries. Water can also be produced as a by-product of some electrochemical reactions, such as in a fuel cell or a metal-air battery.
A part of an electrochemical cell that consists of an electrode and an electrolyte. A half-cell can be connected to another half-cell to form a complete cell. A half-cell has a certain potential that depends on the electrode material and the electrolyte concentration.
A charge method that applies a high current to the battery in a short time. A high-rate charge can reduce the charging time and increase the power output of the battery. It can also cause heat generation, capacity loss, and safety hazards if not controlled properly.
High Rate Discharge
High-rate discharge refers to the ability of a battery to deliver a large amount of current in a short time.
Hydrogen fuel cell
A type of fuel cell that uses hydrogen and oxygen as the fuel and oxidant. It converts the chemical energy of the fuel into electrical energy and water. Hydrogen fuel cell has high efficiency, low emissions, and long lifespan.
A hydrometer is a device used to measure the specific gravity of a liquid, such as the electrolyte in a lead-acid battery, to determine its state of charge.
The International Air Transport Association is a trade association that represents the airline industry. It sets standards and regulations for the transport of passengers and cargo by air. The IATA has specific rules and guidelines for the transport of batteries and battery-powered devices by air.
The International Civil Aviation Organization is a specialized agency of the United Nations that oversees the civil aviation sector. It sets standards and regulations for the safety, security, and efficiency of air transport. It has specific rules and guidelines for the transport of batteries and battery-powered devices by air.
Internal combustion engine: a type of engine that burns a fuel and air mixture inside a cylinder to produce mechanical power. The ICE is used to power vehicles and generators. It has low efficiency, high emissions, and high maintenance costs.
The Institute of Electrical and Electronics Engineers is a professional association that advances the fields of engineering and technology. It publishes standards, journals, and books on various topics, including batteries and energy storage. The IEEE has specific standards and guidelines for the design, testing, and management of batteries and battery systems.
Impedance is a measure of the opposition to the flow of an alternating current in an electrical circuit, including the combined effects of resistance, capacitance, and inductance.
A type of wireless charging that uses an electromagnetic field to transfer energy between two coils. Inductive charging eliminates the need for physical contact and cables. Inductive charging is used to charge devices like smartphones, electric toothbrushes, and electric vehicles.
Internal resistance is the opposition to the flow of current within a battery, causing a voltage drop and power loss during charging and discharging.
Internal Short Circuit
An internal short circuit occurs when an unintended electrical connection forms inside a battery, leading to rapid discharge, overheating or damage.
A device that converts direct current (DC) into alternating current (AC). Inverter is used to power AC loads or devices from a DC source, like a battery or a solar panel. Inverters can have different power ratings, waveforms, and efficiencies.
A unit of energy or work equal to the amount of energy transferred by the force of one newton acting over a distance of one meter. The Joule is used to measure the energy and power of a battery. One joule is equal to one watt-second.
A prefix that means one thousand. Kilo is used to denote the multiples of units, such as kilogram, kilowatt, and kilowatt-hour. Kilo is abbreviated as k.
Lithium cobalt oxide: a type of cathode material for lithium-ion batteries. LCO has high energy density, high voltage, and good cycle life. It is used in consumer electronics, such as laptops, cameras, and phones.
Lithium cobalt: a type of lithium-ion battery that uses lithium cobalt oxide as the cathode material. Li-cobalt has high energy density, high voltage, and good cycle life. It is used in electronics, like laptops, cameras, and phones.
Lithium manganese is a type of lithium-ion battery that uses lithium manganese oxide as the cathode material. Li-manganese has high power density, low cost, and good thermal stability. It is used in power tools, electric bikes, and hybrid electric vehicles.
Lithium phosphate is a type of lithium-ion battery that uses lithium phosphate as the cathode material. Li-phosphate has high safety, long lifespan, and good performance at low temperatures. It is used in medical devices, backup power applications, and electric vehicles.
Lithium polymer is a type of lithium-ion battery that uses a polymer electrolyte instead of a liquid electrolyte. Li-polymer has high energy density, low weight, and flexible shape. Li-polymer is used in a wide range of applications, including smartphones, laptops, electric vehicles, and even spacecraft, due to its unique properties and advantages over other battery technologies.
A lithium-ion battery is a type of rechargeable battery that relies on the movement of lithium ions between the anode and cathode for energy storage and release.
Lithium titanate is a type of anode material for lithium-ion batteries. It has high power density, long cycle life, and good safety. Li-titanate is used in electric vehicles, grid storage, and backup power.
A type of metal-air battery that uses lithium as the anode and oxygen as the cathode. Lithium-air has a very high theoretical energy density but faces a lot of technical challenges, like low efficiency, poor cycle life, and air contamination.
A type of anode material for lithium batteries. Lithium metal has a very high theoretical capacity but has a lot of technical challenges, like dendrite formation, low coulombic efficiency, and safety hazards.
Lithium nickel cobalt aluminum oxide (NCA)
A cathode material for lithium-ion batteries. Lithium nickel cobalt aluminum oxide has high energy density, high power density, and good cycle life. Lithium nickel cobalt aluminum oxide is used in electric vehicles, power tools, and drones.
Lithium nickel manganese cobalt oxide
A cathode material for lithium-ion batteries. Lithium nickel manganese cobalt oxide has high energy density, high power density, and good thermal stability. Lithium nickel manganese cobalt oxide is used in electric vehicles, power tools, and laptops.
A type of lithium battery that uses sulfur as the cathode and lithium metal as the anode. Lithium sulfur has high theoretical energy density but faces several technical challenges, such as low conductivity, polysulfide shuttle, and poor cycle life.
Lithium titanate (LTO)
A type of anode material for lithium-ion batteries. Lithium titanate has high power density, long cycle life, and good safety. Lithium titanate is used in electric vehicles, grid storage, and backup power.
The pattern of voltage, current, and power changes that occur during the operation of a load or a device. Load signature can be used to identify the type, state, and condition of a load or a device. It can also be used to optimize the performance and efficiency of a battery.
A type of battery that does not require periodic addition of water or electrolyte. Maintenance-free batteries are usually sealed and have a valve to release excess gas. More convenient and reliable than conventional batteries.
Memory effect, commonly associated with nickel-cadmium batteries, is a phenomenon where a battery appears to “remember” previous partial discharge levels, causing reduced capacity over time.
A type of battery that uses a metal as the anode and air as the cathode. Metal-air batteries have high theoretical energy density. However, there are downsides like low power density, poor cycle life, and air contamination. Examples of metal-air batteries are zinc-air, aluminum-air, and lithium-air.
Hybrid electric vehicle that uses a start-stop system to turn off the engine when the vehicle is idle. Then it restarts when the driver presses the accelerator. Micro-hybrids use a battery to provide power to the electrical systems and the starter motor. They can reduce fuel consumption and emissions by 5-10%.
A prefix that means one thousandth. Milli is used to denote the fractions of units, such as milligram, milliwatt, and milliampere-hour. Milli is abbreviated as m.
A group of two or more atoms that are bonded together by sharing electrons. Molecules are the building blocks of matter and can have different shapes, sizes, and properties. Molecules are involved in the electrochemical reactions of batteries, such as hydrogen, oxygen, and sulfur.
Metal-oxide-semiconductor field-effect transistor: a type of transistor that uses an electric field to control the flow of current. MOSFET is used in electronic circuits and devices, such as switches, amplifiers, and sensors. Can also be used as a protection device for batteries.
Lithium nickel cobalt aluminum oxide: a type of cathode material for lithium-ion batteries. NCA has high energy density, high power density, and good cycle life. Used in electric vehicles, power tools, and drones.
Lithium nickel manganese cobalt oxide: a cathode material for lithium-ion batteries. NCM has high energy density, high power density, and good thermal stability. Used in electric vehicles, power tools, and laptops.
The negative terminal is the electrode of a battery that connects to the anode and serves as the point where electrons enter the battery during discharge.
Negative temperature coefficient
A property of a material that causes its resistance to decrease as its temperature increases. A negative temperature coefficient describes the behavior of some thermistors, which are devices that measure temperature by measuring resistance. Negative temperature coefficient thermistors are used to monitor the temperature of batteries and chargers.
Rechargeable battery that uses nickel as the cathode and hydrogen as the anode. Nickel hydrogen batteries have high energy density, long cycle life, and good performance at low temperatures. They are used in aerospace and military applications, like satellites and missiles.
A type of rechargeable battery that uses nickel as the cathode and iron as the anode. Nickel iron batteries have low energy density, high self-discharge, and poor performance at high temperatures. Used in backup power and renewable energy systems, such as solar and wind.
Rechargeable battery that uses nickel as the cathode and zinc as the anode. Nickel zinc batteries have high power density, low cost, and good performance at high temperatures. Used in consumer electronics, such as cameras, toys, and flashlights.
Nickel hydrogen: a type of rechargeable battery that uses nickel as the cathode and hydrogen as the anode. NiH2 batteries have high energy density, long cycle life, and good performance at low temperatures. Used in aerospace and military applications, like satellites and missiles.
Nickel iron: a rechargeable battery that uses nickel as the cathode and iron as the anode. NiFe batteries have low energy density, high self-discharge, and poor performance at high temperatures. Used in backup power and renewable energy systems, like solar and wind.
Nickel Zinc: a type of rechargeable battery that uses nickel as the cathode and zinc as the anode. NiZn batteries have high power density, low cost, and good performance at high temperatures. Used in consumer electronics, like cameras, toys, and flashlights.
The amount of energy a battery can deliver under specific conditions. It is often used as a reference value for comparing different batteries.
The established voltage at which a battery is designed to operate, often used as a reference value for battery comparison.
Ohm’s Law states that voltage equals current multiplied by resistance. It can be used to calculate power and energy in a circuit.
Open Circuit Voltage (OCV)
Open Circuit Voltage (OCV) is the voltage of a battery when it is not connected to a load or charging source, indicating its state of charge.
A type of electrolyte that consists of organic solvents and salts. Organic electrolyte is used in lithium-ion and lithium-polymer batteries. Has high conductivity, low viscosity, and a wide voltage range.
Overcharge occurs when a battery is charged beyond its capacity, which can lead to damage, reduced performance, and safety hazards.
A gas that consists of three oxygen atoms. Ozone is a powerful oxidizing agent that can react with organic and inorganic materials. Produced by some electrochemical reactions, like in a metal-air battery or a fuel cell.
In a parallel connection, multiple battery cells or packs are connected in a way that their positive terminals are all connected to a common point, and their negative terminals are connected to another common point. This configuration increases the overall capacity without changing the voltage.
A load that draws current from a battery when the battery is not in use or when the main load is turned off. Can cause self-discharge and the capacity loss of a battery. Can be minimized by using switches, isolators, or disconnects.
The maximum power a battery can deliver briefly. Peak power depends on battery chemistry, state of charge, and temperature.
Proton exchange membrane: a membrane that lets protons pass but blocks electrons and other ions. Used in some fuel cells and electrolyzers.
The ability of a material to let a fluid or a gas pass through. Permeability affects the diffusion and reaction of the electrolyte and the active materials in a battery.
The conversion of light into electricity by a device or a material. Photovoltaic is used in solar cells and panels. Photovoltaic can be combined with batteries to store and supply renewable energy.
Plug-in hybrid electric vehicle: a hybrid vehicle that has a battery that can be recharged by plugging into a power source. PHEV can run on the battery, the engine, or both. PHEVs can reduce fuel consumption and emissions.
The deviation of the cell voltage from the equilibrium voltage due to the resistance and the kinetics of the reactions. Polarization reduces the performance and efficiency of a battery.
Polarity is a term that describes the electrical direction of a battery. Each battery has a positive terminal (+) and a negative terminal (-). The positive terminal provides electric current, while the negative terminal receives it. It is crucial to connect the battery properly in a circuit to ensure the voltage flows in the right direction.
The positive terminal is the electrode of a battery through which the electric current exits the battery. It is typically marked with a “+” symbol and is made of metal with higher electrochemical activity, such as lead dioxide in lead-acid batteries.
Positive temperature coefficient
A property of a material that causes its resistance to increase as its temperature increases. A positive temperature coefficient is used to describe some thermistors that measure temperature by resistance. Positive temperature coefficient thermistors protect the battery from overcurrent and overtemperature.
Chemical element that can react with water and oxygen. Potassium can be used as an electrolyte additive or an electrode material for batteries, like potassium-ion and potassium-air batteries.
The ratio of real power to apparent power in an AC circuit. Power factor indicates the efficiency and quality of the power delivery. It can be improved by using capacitors, inductors, or converters.
A tool that uses an electric motor or an engine to perform a task. Power tools use batteries to provide power and mobility.
Parts per million: a unit of concentration that expresses the amount of a substance in a mixture. PPM is used to measure the impurities, additives, or contaminants in a material. PPM can affect the performance and safety of a battery.
A subatomic particle that has a positive charge and a mass of about 1.67 x 10^-27 kg. Protons are involved in some electrochemical reactions, like in a fuel cell or a proton exchange membrane.
Proton exchange membrane
A membrane that lets protons pass but blocks electrons and other ions. Proton exchange membrane is used in some fuel cells and electrolyzers.
Positive temperature coefficient: a property of a material that causes its resistance to increase as its temperature increases. PTC is used to describe some thermistors that measure temperature by resistance. PTC thermistors protect the battery from overcurrent and overtemperature.
A charge method that applies short and high current pulses to the battery. Pulse charge can improve the charge acceptance, reduce the polarization, and prevent the sulfation of the battery. Used for some lead-acid and nickel-based batteries.
A charge method that applies a high current to the battery in a short time. Quick charge can reduce the charging time and increase the power output of the battery. Can also cause heat generation, capacity loss, and safety hazards.
A graph that shows the relationship between the specific energy and the specific power of a battery or a device. A Ragone plot can be used to compare and optimize the performance and characteristics of different types of batteries or devices.
Rated capacity is the amount of energy a battery can store and discharge under specified conditions. Typically measured in ampere-hours (Ah) or watt-hours (Wh). It indicates the energy a battery can deliver at standard temperature and discharge rate, providing insight into battery performance.
Recombination refers to the process in sealed rechargeable batteries, such as AGM and gel batteries, where oxygen and hydrogen generated during the charging process combine to form water. This process reduces the loss of water and contributes to the maintenance-free nature of these batteries.
The process of restoring the capacity and performance of a battery by applying a series of charge and discharge cycles. Recondition can reverse the effects of memory, sulfation, and passivation of the battery. Used for some nickel-based and lead-acid batteries.
Reduction-oxidation: a type of chemical reaction that involves the transfer of electrons between two substances. Redox is the basis of the electrochemical reactions in a battery. It can be divided into two half-reactions: reduction and oxidation.
Redox flow battery
A type of rechargeable battery that uses liquid electrolytes stored in external tanks. Redox flow battery pumps the electrolytes through a cell stack where the reactions take place. It has high energy density, long cycle life, and flexible design.
A type of additive that transfers electrons between the electrodes to prevent overcharge or over-discharge of a battery. Can improve the safety and lifespan of a battery. Used for some lithium-ion batteries.
A system that recovers the kinetic energy of a vehicle during braking and converts it into electrical energy. Regenerative braking can reduce the fuel consumption and emissions of a vehicle. Can charge the battery of a hybrid or electric vehicle.
A type of battery that is activated by adding a liquid or a gas to the electrolyte. Reserve batteries have a long shelf life and can provide high power in a short time. Used for military and emergency applications.
A device that opposes the flow of current in a circuit. Used to control the voltage, current and power in a circuit. Can also be used to protect the battery from overcurrent and overvoltage.
An alkaline battery that can be recharged by applying a high current pulse. Reusable alkaline has low cost, high capacity, and good performance. Used for low-power devices, such as remote controls and clocks.
The phenomenon of charging a battery with a reversed polarity. Can damage the battery and cause safety hazards like overheating, gas generation, and fire. Reverse Can be prevented by using protection devices, including diodes, FETs, or MOSFETs.
The state of a battery when it reaches its maximum charge or discharge level. Can be indicated by a constant voltage, a low current, or a high temperature. Achieved by applying a constant voltage or a constant current to the battery.
A type of electrochemical cell that can be recharged by reversing the electrochemical reactions. Known as a rechargeable cell or a secondary battery. Can provide multiple charge-discharge cycles and has a longer lifespan than a primary cell.
In a series connection, battery cells or packs are connected end-to-end so that the positive terminal connects to the negative terminal of the adjacent cell or pack. This configuration increases the overall voltage while keeping the capacity the same.
Self-discharge is the gradual loss of energy from a battery while not in use. It is a normal chemical process that occurs within the battery and can lead to a reduction in the state of charge over time, even when disconnected from any circuit.
A separator is a crucial component in battery cells, serving to isolate the positive and negative electrodes. It is typically made of a porous, insulating material that allows the flow of ions between the electrodes while preventing short circuits.
SLA (Sealed Lead Acid) batteries are a type of lead-acid batteries designed for low-maintenance use and ease of handling. They are used in various applications like emergency lighting, alarm systems, and uninterrupted power supplies (UPS).
Service life refers to the expected lifespan of a battery, considering the number of charge-discharge cycles it can endure before its capacity drops to a specified percentage of its initial rated capacity, usually 80%.
A type of cycle that involves a partial discharge and recharge of a battery. Shallow cycles can improve the performance and lifespan of some batteries, like lithium-ion and nickel-metal hydride. Shallow cycle can also cause memory effect in some batteries, such as nickel-cadmium.
A partial depletion of battery charge or energy. Shallow discharge can improve some batteries, like lithium-ion and nickel-metal hydride, but cause memory effect in some batteries, including nickel-cadmium.
Shelf life is the time a battery can be stored without losing a significant portion of its initial capacity. A battery’s shelf life is often influenced by temperature, humidity, and storage conditions.
A connection that bypasses the normal resistance of a circuit. Short circuits can cause high current, heat generation, and damage to the battery and the circuit.
A chemical element that has 47 protons and 47 electrons. Silver is a metal that has high electrical conductivity, corrosion resistance, and catalytic activity. Can be used as an electrode material or an additive for batteries, like silver-zinc and silver-oxide batteries.
A type of primary battery that uses silver oxide as the cathode and zinc as the anode. Silver oxide batteries have high energy density, stable voltage, and long shelf life. Used in watches, calculators, and medical devices.
Sealed lead acid: a type of lead acid battery that has a valve to release excess gas and prevent electrolyte leakage. SLA batteries are maintenance-free, spill-proof, and vibration-resistant. Used in backup power, security, and emergency lighting applications.
An SLI (Starting, Lighting, and Ignition) battery is a lead-acid battery used in vehicles to start the engine and power the lights and other electrical components. It has low internal resistance and delivers maximum current quickly to keep the voltage constant, making it essential for the starter motor, lighting, and ignition system.
A type of battery that has a built-in microchip or circuit that monitors and communicates the battery status. This includes information on voltage, current, temperature, capacity, and state of charge. Smart batteries can optimize the performance and lifespan of the battery and the device. Used in laptops, phones, and electric vehicles.
Charger with a built-in microchip or circuit that controls and adjusts the charging process based on the battery status, such as voltage, current, temperature, capacity, and state of charge. Can improve the charging efficiency and safety of the battery and the charger. Used for lithium-ion and nickel-based batteries.
State of charge: the percentage of the available capacity or energy of a battery at a given time. SOC indicates the remaining runtime or driving range of a battery and the device. SOC can be estimated by measuring the voltage, current, or impedance of the battery.
A chemical element that has 11 protons and 11 electrons. Sodium is a metal that can react with water and oxygen. It can be used as an electrolyte additive or an electrode material for batteries, like sodium-ion and sodium-sulfur batteries.
A type of rechargeable battery that uses sodium ions as the charge carriers between the electrodes. They have low cost, high safety, and good performance at high temperatures. Used in grid storage and electric vehicles.
A type of rechargeable battery that uses sodium as the anode and sulfur as the cathode. Sodium sulfur batteries have high energy density, long cycle life, and low self-discharge. Used in grid storage and electric vehicles.
A device that converts light into electricity by the photovoltaic effect. Solar cells are made of materials, including silicon, perovskite, or organic polymers. Can be combined with batteries to store and supply renewable energy.
A type of electrolyte that has a solid state and does not flow. Solid electrolytes avoid electrolyte leakage, dendrite formation, and side reactions. Solid electrolytes can be used in lithium-ion, lithium metal, and solid-state batteries.
Solid state battery
A battery that uses a solid electrolyte instead of a liquid or a polymer electrolyte. Have high energy density, high safety, and long lifespans. Solid-state batteries are used in consumer electronics, medical devices, and electric vehicles.
The amount of energy per unit mass of a battery or a device. Specific energy is measured in watt-hours per kilogram (Wh/kg) or joules per kilogram (J/kg). Specific energy indicates the weight and endurance of a battery or a device.
The amount of power per unit mass of a battery or a device. Specific power is measured in watts per kilogram (W/kg) or joules per second per kilogram (J/s/kg). Specific power indicates the acceleration and performance of a battery or a device.
A crystal structure that has a cubic symmetry and a general formula of AB2O4. Spinel is used as a cathode material for lithium-ion batteries, like lithium manganese oxide and lithium nickel manganese cobalt oxide. Has high power density, low cost, and good thermal stability.
An electrode design that coils the electrodes and the separators into a cylindrical shape. Spiral wound electrodes have high power density, low internal resistance, and good heat dissipation. Used in lithium-ion and nickel-metal hydride batteries.
The current that is drawn from a battery when the battery is not in use or when the main load is turned off. Standby current can cause self-discharge and capacity loss of a battery. You can minimize standby currents by implementing switches, isolators, or disconnects.
Standby service is a battery application where the battery is kept in a charged state and ready to provide backup power in case of mains power failure, such as in UPS systems or emergency lighting. The battery remains on standby most of the time, only discharging during power outages.
State of Charge (SoC)
State of Charge (SoC) is a term used to describe the current charge level of a battery relative to its total capacity, expressed as a percentage. It helps to determine the available energy left in a battery during its discharge cycle.
State-of-function: The ability of a battery to perform its intended function, such as starting a vehicle, powering a device, or storing energy. State-of-function depends on the chemistry, design, and usage of the battery. The power, energy, or voltage of the battery can measure state-of-function.
State of Health (SoH)
State of Health (SoH) is a metric that represents the overall condition of a battery. It considers factors like age, cycling history, and temperature exposure. Provides insight into the remaining useful life of the battery.
Sulfation is a chemical process in lead-acid batteries. Lead sulfate crystals form on battery plates during discharge. If batteries are not fully recharged sulfate accumulates, leading to capacity reduction and reduced battery life.
A chemical element that has 16 protons and 16 electrons. Sulfur is a nonmetal that can react with metals and oxygen. It can be used as a cathode material for batteries, such as lithium-sulfur and sodium-sulfur batteries.
An acid consisting of hydrogen, sulfur, and oxygen. Sulfuric acid is used as an electrolyte for lead acid batteries. It has high conductivity, corrosivity, and density.
A device that stores electrical energy by creating an electric field between two electrodes separated by an electrolyte. Also known as an electric double-layer capacitor or ultracapacitor. Has high power density, fast charging and discharging, and long cycle life.
The charge that remains on the surface of the electrodes after charging or discharging a battery. Surface charge can affect the voltage and the state of charge measurements of the battery. Surface charge can be removed by applying a load or waiting for some time.
The expansion of the volume of a battery due to gas generation, electrolyte decomposition, or electrode degradation. Swelling can reduce the performance and safety of the battery. Can be caused by overcharge, over-discharge, overtemperature, or mechanical stress.
Switch mode charger
A charger that uses a switching device to convert the input AC voltage to a DC voltage. It can adjust the output voltage and current according to the battery status and the charging algorithm. Highly efficient, low weight, and wide input range.
Total cost of ownership: the sum of all the costs associated with owning and operating a battery or a device. TCO includes the initial purchase cost, the operating cost, the maintenance cost, and the disposal cost. Can be used to compare and optimize the economic value of different types of batteries or devices.
The temperature coefficient is a measure of how much a material’s physical property changes when the temperature changes. It is used to describe the behavior of materials like resistors, thermistors, and electrodes. The temperature coefficient can affect how well a battery works and how safe it is to use
Thermal runaway is a dangerous condition in which a battery’s temperature continues to rise and may result in a fire or explosion. It occurs due to internal heat generation from chemical reactions within the battery and can be triggered by overcharging, short-circuiting, or excessive discharge.
Thin film battery
A type of battery that uses thin layers of materials as the electrodes and the electrolyte. Thin film batteries have high energy density, low weight, and flexible shape. Used in wearable devices, smart cards, and sensors.
A type of AC power supply with three sinusoidal voltages that are 120 degrees out of phase.
A charging method with three stages: bulk, absorption, and float. It prevents overcharging and self-discharge of the battery.
The minimum voltage needed to turn on a transistor or a diode.
A measure of how fast a capacitor charges or discharges through a resistor. It is equal to the resistance times the capacitance.
A battery that has the best performance, quality, or reliability among other batteries of the same type or category.
Total harmonic distortion
A measure of how much a waveform deviates from a pure sinusoid due to harmonics. Harmonics are frequencies that are multiples of the fundamental frequency.
A charging method that delivers a very low current to the battery to keep it fully charged or to compensate for self-discharge.
A positive plate used in lead-acid batteries. It has cylindrical tubes filled with lead oxide paste. Tubular plates have a higher surface area and a lower internal resistance than flat plates.
A type of capacitor that has a very high capacitance and a low voltage rating. Ultracapacitors can store and release large amounts of energy in a short time.
Uninterruptible Power Supply: a device that provides backup power to a load in case of a power outage or a voltage fluctuation.
An acronym for universal serial bus, a standard for connecting peripheral devices to a computer or a charger. A USB cable has four wires: two for power and two for data.
Valve Regulated Lead Acid (VRLA) Battery
A Valve Regulated Lead Acid (VRLA) battery is a sealed lead-acid battery with a built-in pressure relief valve. The valve allows the battery to release excess gas pressure, which may build up during charging, and prevents overpressure-related damage. VRLA batteries include AGM and gel batteries.
A type of battery cell that has a vent or a hole that allows the release of gas or electrolyte. Vented cells require periodic maintenance, like adding water or electrolyte.
A unit of electric potential difference or electromotive force. One volt is equal to the potential difference across a conductor when a current of one ampere dissipates one watt of power.
The electric potential difference between two points in a circuit. Voltage is measured in volts and is the driving force for electric current.
A phenomenon that occurs when a battery is repeatedly discharged and recharged at a low level, resulting in a reduced capacity and voltage. It is also known as memory effect or lazy battery effect.
The decrease in voltage across a component or a section of a circuit due to the resistance or impedance of the component or the section.
The maximum or minimum voltage that a battery can safely operate at. Exceeding the voltage limit can damage the battery or cause safety issues.
The process of ensuring that the voltages of two or more batteries or cells are equal or compatible when they are connected in series or parallel. Voltage matching can improve the performance and efficiency of the battery system.
A temporary reduction in voltage due to a high demand or a fault in the power system. Voltage sag can cause malfunction or damage to sensitive equipment.
An acronym for valve-regulated lead acid, a type of sealed lead-acid battery that has a valve mechanism that allows the escape of excess gas. VRLA batteries are also known as maintenance-free batteries or sealed lead-acid batteries.
A watt is the unit of measurement for power, the rate at which energy is transferred or converted. In battery systems, wattage is used to indicate the amount of power a battery can supply for a specific duration.
A Watt-hour is a unit of energy equivalent to the power consumption of one watt for one hour. It is used to quantify the amount of energy stored in a battery and helps to estimate runtime for different loads. Watt-hour = voltage (V) × ampere-hour (Ah).
A type of battery cell that has a liquid electrolyte that can spill or leak. Wet cells are usually found in lead-acid batteries or nickel-iron batteries. Require periodic maintenance, like adding water or electrolyte.
An acronym for wireless power transfer or wireless power consortium: a technology or an organization that enables the transfer of electric power without wires or cables. WPC uses electromagnetic induction or resonance to transfer power between a transmitter and a receiver.
A metal used as an anode material in some types of batteries, such as zinc-carbon, zinc-air, or zinc-bromine. Zinc has a low cost, high energy density, and good shelf life but also suffers from corrosion and dendrite formation.
A type of battery that uses zinc as the anode and oxygen from the air as the cathode. Zinc air batteries have a high energy density, low cost, and long shelf life. But they also have a low power density, limited discharge rate, and poor low-temperature performance.
A type of battery that uses zinc as the anode and bromine as the cathode. Zinc bromide batteries have a high energy density, high power density, and long cycle life, but they also have a high cost, high toxicity, and complex design.
A type of battery that uses zinc as the anode and manganese dioxide as the cathode. Zinc carbon batteries are also known as dry cells or Leclanche cells. They have a low cost, wide availability, and good shelf life, but they also have a low capacity, low voltage, and poor performance at high currents or low temperatures.
A type of battery that uses zinc as the anode and manganese dioxide as the cathode. They are usually heavy-duty or extra-heavy-duty batteries. They have a higher capacity, higher voltage, and better performance than zinc carbon batteries, but they also have a shorter shelf life and higher self-discharge rate.
Zinc manganese dioxide
A type of battery that uses zinc as the anode and manganese dioxide as the cathode. Also known as alkaline batteries or LR batteries. Zinc manganese dioxide batteries have a higher capacity, higher voltage, and better performance than zinc carbon or zinc chloride batteries, but they also have a higher cost and lower shelf life.
An abbreviation for zinc bromide, a type of battery that uses zinc as the anode and bromine as the cathode. ZnBr batteries have a high energy density, high power density, and long cycle life, but they also have a high cost, high toxicity, and complex design.